1
|
Tsai MS, Domroes T, Pentidis N, Koschinski S, Schroll A, Bohm S, Arampatzis A, Mersmann F. Effect of the temporal coordination and volume of cyclic mechanical loading on human Achilles tendon adaptation in men. Sci Rep 2024; 14:6875. [PMID: 38519507 PMCID: PMC10960029 DOI: 10.1038/s41598-024-56840-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 03/12/2024] [Indexed: 03/25/2024] Open
Abstract
Human tendons adapt to mechanical loading, yet there is little information on the effect of the temporal coordination of loading and recovery or the dose-response relationship. For this reason, we assigned adult men to either a control or intervention group. In the intervention group, the two legs were randomly assigned to one of five high-intensity Achilles tendon (AT) loading protocols (i.e., 90% maximum voluntary contraction and approximately 4.5 to 6.5% tendon strain) that were systematically modified in terms of loading frequency (i.e., sessions per week) and overall loading volume (i.e., total time under loading). Before, at mid-term (8 weeks) and after completion of the 16 weeks intervention, AT mechanical properties were determined using a combination of inverse dynamics and ultrasonography. The cross-sectional area (CSA) and length of the free AT were measured using magnetic resonance imaging pre- and post-intervention. The data analysis with a linear mixed model showed significant increases in muscle strength, rest length-normalized AT stiffness, and CSA of the free AT in the intervention group (p < 0.05), yet with no marked differences between protocols. No systematic effects were found considering the temporal coordination of loading and overall loading volume. In all protocols, the major changes in normalized AT stiffness occurred within the first 8 weeks and were mostly due to material rather than morphological changes. Our findings suggest that-in the range of 2.5-5 sessions per week and 180-300 s total high strain loading-the temporal coordination of loading and recovery and overall loading volume is rather secondary for tendon adaptation.
Collapse
Affiliation(s)
- Meng-Shiuan Tsai
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Theresa Domroes
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Nikolaos Pentidis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Sophia Koschinski
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Arno Schroll
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.
- Berlin School of Movement Science, Berlin, Germany.
| |
Collapse
|
2
|
Mersmann F, Domroes T, Tsai MS, Pentidis N, Schroll A, Bohm S, Arampatzis A. Longitudinal Evidence for High-Level Patellar Tendon Strain as a Risk Factor for Tendinopathy in Adolescent Athletes. SPORTS MEDICINE - OPEN 2023; 9:83. [PMID: 37673828 PMCID: PMC10482817 DOI: 10.1186/s40798-023-00627-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 08/07/2023] [Indexed: 09/08/2023]
Abstract
BACKGROUND High tendon strain leads to sub-rupture fatigue damage and net-catabolic signaling upon repetitive loading. While high levels of tendon strain occur in adolescent athletes at risk for tendinopathy, a direct association has not yet been established. Therefore, in this prospective longitudinal study, we examined the hypothesis that adolescent athletes who develop patellar tendon pain have shown increased levels of strain in advance. METHODS In 44 adolescent athletes (12-17 years old), patellar tendon mechanical properties were measured using ultrasonography and inverse dynamics at four time points during a season. Fourteen athletes developed clinically relevant tendon pain (SYM; i.e., reduction of the VISA-P score of at least 13 points), while 23 remained asymptomatic (ASYM; VISA-P score of > 87 points). Seven cases did not fall into one of these categories and were excluded. Tendon mechanical properties of SYM in the session before the development of symptoms were compared to a randomly selected session in ASYM. RESULTS Tendon strain was significantly higher in SYM compared to ASYM (p = 0.03). The risk ratio for developing symptoms was 2.3-fold higher in athletes with tendon strain ≥9% (p = 0.026). While there was no clear evidence for systematic differences of the force applied to the tendon or tendon stiffness between SYM and ASYM (p > 0.05), subgroup analysis indicated that tendon force increased prior to the development of symptoms only in SYM (p = 0.034). DISCUSSIO The study provides novel longitudinal evidence that high tendon strain could be an important risk factor for patellar tendinopathy in adolescent athletes. We suggest that inadequate adaptation of tendon stiffness to increases in muscle strength may occur if adolescent athletes are subject to mechanical loading which does not provide effective tendon stimulation.
Collapse
Affiliation(s)
- Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany.
- Berlin School of Movement Science, Berlin, Germany.
| | - Theresa Domroes
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Meng-Shiuan Tsai
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Nikolaos Pentidis
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Arno Schroll
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität Zu Berlin, Unter Den Linden 6, 10099, Berlin, Germany
- Berlin School of Movement Science, Berlin, Germany
| |
Collapse
|
3
|
Ito K, Go Y, Tatsumoto S, Usui C, Mizuno Y, Ikami E, Isozaki Y, Usui M, Kajihara T, Yoda T, Inoue KI, Takada M, Sato T. Gene expression profiling of the masticatory muscle tendons and Achilles tendons under tensile strain in the Japanese macaque Macaca fuscata. PLoS One 2023; 18:e0280649. [PMID: 36656905 PMCID: PMC9851512 DOI: 10.1371/journal.pone.0280649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 01/05/2023] [Indexed: 01/20/2023] Open
Abstract
Both Achilles and masticatory muscle tendons are large load-bearing structures, and excessive mechanical loading leads to hypertrophic changes in these tendons. In the maxillofacial region, hyperplasia of the masticatory muscle tendons and aponeurosis affect muscle extensibility resulting in limited mouth opening. Although gene expression profiles of Achilles and patellar tendons under mechanical strain are well investigated in rodents, the gene expression profile of the masticatory muscle tendons remains unexplored. Herein, we examined the gene expression pattern of masticatory muscle tendons and compared it with that of Achilles tendons under tensile strain conditions in the Japanese macaque Macaca fuscata. Primary tenocytes isolated from the masticatory muscle tendons (temporal tendon and masseter aponeurosis) and Achilles tendons were mechanically loaded using the tensile force and gene expression was analyzed using the next-generation sequencing. In tendons exposed to tensile strain, we identified 1076 differentially expressed genes with a false discovery rate (FDR) < 10-10. To identify genes that are differentially expressed in temporal tendon and masseter aponeurosis, an FDR of < 10-10 was used, whereas the FDR for Achilles tendons was set at > 0.05. Results showed that 147 genes are differentially expressed between temporal tendons and masseter aponeurosis, out of which, 125 human orthologs were identified using the Ensemble database. Eight of these orthologs were related to tendons and among them the expression of the glycoprotein nmb and sphingosine kinase 1 was increased in temporal tendons and masseter aponeurosis following exposure to tensile strain. Moreover, the expression of tubulin beta 3 class III, which promotes cell cycle progression, and septin 9, which promotes cytoskeletal rearrangements, were decreased in stretched Achilles tendon cells and their expression was increased in stretched masseter aponeurosis and temporal tendon cells. In conclusion, cyclic strain differentially affects gene expression in Achilles tendons and tendons of the masticatory muscles.
Collapse
Affiliation(s)
- Ko Ito
- Department of Oral and Maxillofacial Surgery, Saitama Medical University, Saitama, Japan
| | - Yasuhiro Go
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Science, Okazaki, Aichi, Japan
- Department of System Neuroscience, National Institute for Physiological Science, Okazaki, Aichi, Japan
- Department of Physiological Science, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Shoji Tatsumoto
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Science, Okazaki, Aichi, Japan
| | - Chika Usui
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Science, Okazaki, Aichi, Japan
| | - Yosuke Mizuno
- Division of Morphological Science, Biomedical Research Center, Saitama Medical University, Saitama, Japan
| | - Eiji Ikami
- Department of Oral and Maxillofacial Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Yuta Isozaki
- Department of Oral and Maxillofacial Surgery, Saitama Medical University, Saitama, Japan
| | - Michihiko Usui
- Division of Periodontology, Department of Cardiology and Periodontology, Kyushu Dental University, Fukuoka, Japan
| | - Takeshi Kajihara
- Department of Obstetrics and Gynecology, Saitama Medical University, Saitama, Japan
| | - Tetsuya Yoda
- Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ken-ichi Inoue
- Systems Neuroscience Section, Department of Neuroscience, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Masahiko Takada
- Systems Neuroscience Section, Department of Neuroscience, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Tsuyoshi Sato
- Department of Oral and Maxillofacial Surgery, Saitama Medical University, Saitama, Japan
- * E-mail:
| |
Collapse
|
4
|
Lazarczuk SL, Maniar N, Opar DA, Duhig SJ, Shield A, Barrett RS, Bourne MN. Mechanical, Material and Morphological Adaptations of Healthy Lower Limb Tendons to Mechanical Loading: A Systematic Review and Meta-Analysis. Sports Med 2022; 52:2405-2429. [PMID: 35657492 PMCID: PMC9474511 DOI: 10.1007/s40279-022-01695-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND Exposure to increased mechanical loading during physical training can lead to increased tendon stiffness. However, the loading regimen that maximises tendon adaptation and the extent to which adaptation is driven by changes in tendon material properties or tendon geometry is not fully understood. OBJECTIVE To determine (1) the effect of mechanical loading on tendon stiffness, modulus and cross-sectional area (CSA); (2) whether adaptations in stiffness are driven primarily by changes in CSA or modulus; (3) the effect of training type and associated loading parameters (relative intensity; localised strain, load duration, load volume and contraction mode) on stiffness, modulus or CSA; and (4) whether the magnitude of adaptation in tendon properties differs between age groups. METHODS Five databases (PubMed, Scopus, CINAHL, SPORTDiscus, EMBASE) were searched for studies detailing load-induced adaptations in tendon morphological, material or mechanical properties. Standardised mean differences (SMDs) with 95% confidence intervals (CIs) were calculated and data were pooled using a random effects model to estimate variance. Meta regression was used to examine the moderating effects of changes in tendon CSA and modulus on tendon stiffness. RESULTS Sixty-one articles met the inclusion criteria. The total number of participants in the included studies was 763. The Achilles tendon (33 studies) and the patella tendon (24 studies) were the most commonly studied regions. Resistance training was the main type of intervention (49 studies). Mechanical loading produced moderate increases in stiffness (standardised mean difference (SMD) 0.74; 95% confidence interval (CI) 0.62-0.86), large increases in modulus (SMD 0.82; 95% CI 0.58-1.07), and small increases in CSA (SMD 0.22; 95% CI 0.12-0.33). Meta-regression revealed that the main moderator of increased stiffness was modulus. Resistance training interventions induced greater increases in modulus than other training types (SMD 0.90; 95% CI 0.65-1.15) and higher strain resistance training protocols induced greater increases in modulus (SMD 0.82; 95% CI 0.44-1.20; p = 0.009) and stiffness (SMD 1.04; 95% CI 0.65-1.43; p = 0.007) than low-strain protocols. The magnitude of stiffness and modulus differences were greater in adult participants. CONCLUSIONS Mechanical loading leads to positive adaptation in lower limb tendon stiffness, modulus and CSA. Studies to date indicate that the main mechanism of increased tendon stiffness due to physical training is increased tendon modulus, and that resistance training performed at high compared to low localised tendon strains is associated with the greatest positive tendon adaptation. PROSPERO registration no.: CRD42019141299.
Collapse
Affiliation(s)
- Stephanie L Lazarczuk
- School of Health Sciences and Social Work, Griffith University, Gold Coast, QLD, Australia.
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia.
| | - Nirav Maniar
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
- Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Melbourne, VIC, Australia
| | - David A Opar
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
- Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Melbourne, VIC, Australia
| | - Steven J Duhig
- School of Health Sciences and Social Work, Griffith University, Gold Coast, QLD, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Anthony Shield
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Rod S Barrett
- School of Health Sciences and Social Work, Griffith University, Gold Coast, QLD, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Matthew N Bourne
- School of Health Sciences and Social Work, Griffith University, Gold Coast, QLD, Australia
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| |
Collapse
|
5
|
Merry K, Napier C, Waugh CM, Scott A. Foundational Principles and Adaptation of the Healthy and Pathological Achilles Tendon in Response to Resistance Exercise: A Narrative Review and Clinical Implications. J Clin Med 2022; 11:4722. [PMID: 36012960 PMCID: PMC9410084 DOI: 10.3390/jcm11164722] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 12/03/2022] Open
Abstract
Therapeutic exercise is widely considered a first line fundamental treatment option for managing tendinopathies. As the Achilles tendon is critical for locomotion, chronic Achilles tendinopathy can have a substantial impact on an individual's ability to work and on their participation in physical activity or sport and overall quality of life. The recalcitrant nature of Achilles tendinopathy coupled with substantial variation in clinician-prescribed therapeutic exercises may contribute to suboptimal outcomes. Further, loading the Achilles tendon with sufficiently high loads to elicit positive tendon adaptation (and therefore promote symptom alleviation) is challenging, and few works have explored tissue loading optimization for individuals with tendinopathy. The mechanism of therapeutic benefit that exercise therapy exerts on Achilles tendinopathy is also a subject of ongoing debate. Resultingly, many factors that may contribute to an optimal therapeutic exercise protocol for Achilles tendinopathy are not well described. The aim of this narrative review is to explore the principles of tendon remodeling under resistance-based exercise in both healthy and pathologic tissues, and to review the biomechanical principles of Achilles tendon loading mechanics which may impact an optimized therapeutic exercise prescription for Achilles tendinopathy.
Collapse
Affiliation(s)
- Kohle Merry
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Christopher Napier
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Charlie M. Waugh
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| | - Alex Scott
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Centre for Hip Health and Mobility, Vancouver, BC V5Z 1M9, Canada
| |
Collapse
|
6
|
Benage LG, Sweeney JD, Giers MB, Balasubramanian R. Dynamic Load Model Systems of Tendon Inflammation and Mechanobiology. Front Bioeng Biotechnol 2022; 10:896336. [PMID: 35910030 PMCID: PMC9335371 DOI: 10.3389/fbioe.2022.896336] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 06/22/2022] [Indexed: 11/25/2022] Open
Abstract
Dynamic loading is a shared feature of tendon tissue homeostasis and pathology. Tendon cells have the inherent ability to sense mechanical loads that initiate molecular-level mechanotransduction pathways. While mature tendons require physiological mechanical loading in order to maintain and fine tune their extracellular matrix architecture, pathological loading initiates an inflammatory-mediated tissue repair pathway that may ultimately result in extracellular matrix dysregulation and tendon degeneration. The exact loading and inflammatory mechanisms involved in tendon healing and pathology is unclear although a precise understanding is imperative to improving therapeutic outcomes of tendon pathologies. Thus, various model systems have been designed to help elucidate the underlying mechanisms of tendon mechanobiology via mimicry of the in vivo tendon architecture and biomechanics. Recent development of model systems has focused on identifying mechanoresponses to various mechanical loading platforms. Less effort has been placed on identifying inflammatory pathways involved in tendon pathology etiology, though inflammation has been implicated in the onset of such chronic injuries. The focus of this work is to highlight the latest discoveries in tendon mechanobiology platforms and specifically identify the gaps for future work. An interdisciplinary approach is necessary to reveal the complex molecular interplay that leads to tendon pathologies and will ultimately identify potential regenerative therapeutic targets.
Collapse
Affiliation(s)
- Lindsay G. Benage
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, United States
| | - James D. Sweeney
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, United States
| | - Morgan B. Giers
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, United States
- *Correspondence: Morgan B. Giers,
| | - Ravi Balasubramanian
- School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR, United States
- School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Corvallis, OR, United States
| |
Collapse
|
7
|
McMahon G. No Strain, No Gain? The Role of Strain and Load Magnitude in Human Tendon Responses and Adaptation to Loading. J Strength Cond Res 2022; 36:2950-2956. [DOI: 10.1519/jsc.0000000000004288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
8
|
Ramos-Mucci L, Elsheikh A, Keenan C, Eliasy A, D'Aout K, Bou-Gharios G, Comerford E, Poulet B. The anterior cruciate ligament in murine post-traumatic osteoarthritis: markers and mechanics. Arthritis Res Ther 2022; 24:128. [PMID: 35637500 PMCID: PMC9150328 DOI: 10.1186/s13075-022-02798-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 05/03/2022] [Indexed: 11/24/2022] Open
Abstract
Background Knee joint injuries, common in athletes, have a high risk of developing post-traumatic osteoarthritis (PTOA). Ligaments, matrix-rich connective tissues, play important mechanical functions stabilising the knee joint, and yet their role post-trauma is not understood. Recent studies have shown that ligament extracellular matrix structure is compromised in the early stages of spontaneous osteoarthritis (OA) and PTOA, but it remains unclear how ligament matrix pathology affects ligament mechanical function. In this study, we aim to investigate both structural and mechanical changes in the anterior cruciate ligament (ACL) in a mouse model of knee trauma. Methods Knee joints were analysed following non-invasive mechanical loading in male C57BL/6 J mice (10-week-old). Knee joints were analysed for joint space mineralisation to evaluate OA progression, and the ACLs were assessed with histology and mechanical testing. Results Joints with PTOA had a 33–46% increase in joint space mineralisation, indicating OA progression. Post-trauma ACLs exhibited extracellular matrix modifications, including COL2 and proteoglycan deposition. Additional changes included cells expressing chondrogenic markers (SOX9 and RUNX2) expanding from the ACL tibial enthesis to the mid-substance. Viscoelastic and mechanical changes in the ACLs from post-trauma knee joints included a 20–21% decrease in tangent modulus at 2 MPa of stress, a decrease in strain rate sensitivity at higher strain rates and an increase in relaxation during stress-relaxation, but no changes to hysteresis and ultimate load to failure were observed. Conclusions These results demonstrate that ACL pathology and viscoelastic function are compromised in the post-trauma knee joint and reveal an important role of viscoelastic mechanical properties for ligament and potentially knee joint health. Supplementary Information The online version contains supplementary material available at 10.1186/s13075-022-02798-7.
Collapse
Affiliation(s)
- Lorenzo Ramos-Mucci
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK
| | - Ahmed Elsheikh
- School of Engineering, University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, 100083, China.,NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - Craig Keenan
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK.,Faculty of Health, Social Care and Medicine, Edge Hill University, St Helens Road, Ormskirk, Lancashire, L39 4QP, UK
| | - Ashkan Eliasy
- School of Engineering, University of Liverpool, Brownlow Hill, Liverpool, L69 3GH, UK
| | - Kristiaan D'Aout
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK
| | - George Bou-Gharios
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK
| | - Eithne Comerford
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK.,School of Veterinary Science, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Rd, Neston, CH64 7TE, UK
| | - Blandine Poulet
- Institute of Life Course and Medical Sciences, University of Liverpool, Apex building, West Derby street, Liverpool, L7 8TX, UK.
| |
Collapse
|
9
|
Merza EY, Pearson SJ, Lichtwark GA, Malliaras P. The acute effects of higher versus lower load duration and intensity on morphological and mechanical properties of the healthy Achilles tendon: a randomized crossover trial. J Exp Biol 2022; 225:275126. [PMID: 35470387 PMCID: PMC9167578 DOI: 10.1242/jeb.243741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 04/19/2022] [Indexed: 11/20/2022]
Abstract
The Achilles tendon (AT) exhibits volume changes related to fluid flow under acute load which may be linked to changes in stiffness. Fluid flow provides a mechanical signal for cellular activity and may be one mechanism that facilitates tendon adaptation. This study aimed to investigate whether isometric intervention involving a high level of load duration and intensity could maximize the immediate reduction in AT volume and stiffness compared with interventions involving a lower level of load duration and intensity. Sixteen healthy participants (12 males, 4 females; age 24.4±9.4 years, body mass 70.9±16.1 kg, height 1.7±0.1 m) performed three isometric interventions of varying levels of load duration (2 s and 8 s) and intensity (35% and 75% maximal voluntary isometric contraction) over a 3 week period. Freehand 3D ultrasound was used to measure free AT volume (at rest) and length (at 35%, 55% and 75% of maximum plantarflexion force) pre- and post-interventions. The slope of the force–elongation curve over these force levels represented individual stiffness (N mm−1). Large reductions in free AT volume and stiffness resulted in response to long-duration high-intensity loading whilst less reduction was produced with a lower load intensity. In contrast, no change in free AT volume and a small increase in AT stiffness occurred with lower load duration. These findings suggest that the applied load on the AT must be heavy and sustained for a long duration to maximize immediate volume reduction, which might be an acute response that enables optimal long-term tendon adaptation via mechanotransduction pathways. Summary: High levels of load duration and intensity have the greatest acute effect on the free Achilles tendon volume and stiffness.
Collapse
Affiliation(s)
- Eman Y Merza
- Department of physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston Vic 3199, Melbourne, Australia
| | - Stephen J Pearson
- Centre for Health, Sport and Rehabilitation Sciences Research, University of Salford, Greater Manchester, M5 4WT, UK
| | - Glen A Lichtwark
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St. Lucia, QLD 4072, Brisbane, Australia
| | - Peter Malliaras
- Department of physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston Vic 3199, Melbourne, Australia
| |
Collapse
|
10
|
Egerbacher M, Gardner K, Caballero O, Hlavaty J, Schlosser S, Arnoczky SP, Lavagnino M. Stress-deprivation induces an up-regulation of versican and connexin-43 mRNA and protein synthesis and increased ADAMTS-1 production in tendon cells in situ. Connect Tissue Res 2022; 63:43-52. [PMID: 33467936 DOI: 10.1080/03008207.2021.1873302] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Purpose: The proper function of the tenocyte network depends on cell-matrix as well as intercellular communication that is mechanosensitive. Building on the concept that the etiopathogenic stimulus for tendon degeneration is the catabolic response of tendon cells to mechanobiologic under-stimulation, we studied the pericellular matrix rich in versican and its predominant proteolytic enzyme ADAMTS-1, as well as Connexin-43 (Cx43), a major gap junction forming protein in tendons, in stress-deprived rat tail tendon fascicles (RTTfs).Materials and Methods: RTTfs were stress-deprived for up to 7 days under tissue culture conditions. RT-qPCR was used to measure mRNA expression of versican, ADAMTS-1, and Cx43. Protein synthesis was determined using Western blotting and immunohistochemistry.Results: Stress-deprivation (SD) caused a statistically significant up-regulation of versican, ADAMTS-1, and Cx43 mRNA expression that was persistent over the 7-day test period. Western blot analysis and immunohistochemical assessment of protein synthesis revealed a marked increase of the respective proteins with SD. Inhibition of proteolytic enzyme activity with ilomastat prevented the increased versican degradation and Cx43 synthesis in 3 days stress-deprived tendons when compared with non-treated, stress-deprived tendons.Conclusion: In the absence of mechanobiological signaling the immediate pericellular matrix is modulated as tendon cells up-regulate their production of ADAMTS-1, and versican with subsequent proteoglycan degradation potentially leading to cell signaling cues increasing Cx43 gap junctional protein. The results also provide further support for the hypothesis that the cellular changes associated with tendinopathy are a result of decreased mechanobiological signaling and a loss of homeostatic cytoskeletal tension.
Collapse
Affiliation(s)
- Monika Egerbacher
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Keri Gardner
- Laboratory for Comparative Orthopaedic Research, Michigan State University, East Lansing, MI, USA
| | - Oscar Caballero
- Laboratory for Comparative Orthopaedic Research, Michigan State University, East Lansing, MI, USA
| | - Juraj Hlavaty
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Sarah Schlosser
- VetCORE Facility for Research, University of Veterinary Medicine, Vienna, Austria
| | - Steven P Arnoczky
- Laboratory for Comparative Orthopaedic Research, Michigan State University, East Lansing, MI, USA
| | - Michael Lavagnino
- Laboratory for Comparative Orthopaedic Research, Michigan State University, East Lansing, MI, USA.,Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA
| |
Collapse
|
11
|
Rice PE, Nishikawa K, Nimphius S. Isolated Joint Block Progression Training Improves Leaping Performance in Dancers. Front Sports Act Living 2022; 3:779824. [PMID: 34970645 PMCID: PMC8712483 DOI: 10.3389/fspor.2021.779824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 11/15/2021] [Indexed: 11/29/2022] Open
Abstract
The purpose of this study was to investigate the effect of a 12-week ankle-specific block progression training program on saut de chat leaping performance [leap height, peak power (PP), joint kinetics and kinematics], maximal voluntary isometric plantar flexion (MVIP) strength, and Achilles tendon (AT) stiffness. Dancers (training group n = 7, control group n = 7) performed MVIP at plantarflexed (10◦) and neutral ankle positions (0◦) followed by ramping isometric contractions equipped with ultrasound to assess strength and AT stiffness, respectively. Dancers also performed saut de chat leaps surrounded by 3-D motion capture atop force platforms to determine center of mass and joint kinematics and kinetics. The training group then followed a 12-week ankle-focused program including isometric, dynamic constant external resistance, accentuated eccentric loading, and plyometric training modalities, while the control group continued dancing normally. We found that the training group's saut de chat ankle PP (59.8%), braking ankle stiffness (69.6%), center of mass PP (11.4%), and leap height (12.1%) significantly increased following training. We further found that the training group's MVIP significantly increased at 10◦ (17.0%) and 0◦ (12.2%) along with AT stiffness (29.6%), while aesthetic leaping measures were unchanged (peak split angle, mean trunk angle, trunk angle range). Ankle-specific block progression training appears to benefit saut de chat leaping performance, PP output, ankle-joint kinetics, maximal strength, and AT stiffness, while not affecting kinematic aesthetic measures. We speculate that the combined training blocks elicited physiological changes and enhanced neuromuscular synchronization for increased saut de chat leaping performance in this cohort of dancers.
Collapse
Affiliation(s)
- Paige E Rice
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Department of Health and Exercise Science, Wake Forest University, Winston Salem, NC, United States.,Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, United States
| | - Kiisa Nishikawa
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, United States
| | - Sophia Nimphius
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| |
Collapse
|
12
|
Taguchi T, Zhang N, Angibeau D, Spivey KP, Lopez MJ. Evaluation of canine adipose-derived multipotent stromal cell differentiation to ligamentoblasts on tensioned collagen type I templates in a custom bioreactor culture system. Am J Vet Res 2021; 82:924-934. [PMID: 34669492 DOI: 10.2460/ajvr.82.11.924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate differentiation of canine adipose-derived multipotent stromal cells (ASCs) into ligamentoblasts on tensioned collagen type I (Col1) templates in a perfusion culture system. SAMPLES Infrapatellar fat pad ASCs from healthy stifle joints of 6 female mixed-breed dogs. PROCEDURES Third-passage ASCs (6 × 106 cells/template) were loaded onto suture-augmented Col1 templates under 15% static strain in perfusion bioreactors. Forty-eight ASC-Col1 constructs were incubated with ligamentogenic (ligamentogenic constructs; n = 24) or stromal medium (stromal constructs; 24) for up to 21 days. Specimens were collected from each construct after 2 hours (day 0) and 7, 14, and 21 days of culture. Cell number, viability, distribution, and morphology; construct collagen content; culture medium procollagen-I-N-terminal peptide concentration; and gene expression were compared between ligamentogenic and stromal constructs. RESULTS ASCs adhered to collagen fibers. Cell numbers increased from days 0 to 7 and days 14 to 21 for both construct types. Relative to stromal constructs, cell morphology and extracellular matrix were more mature and collagen content on day 21 and procollagen-I-N-terminal peptide concentration on days 7 and 21 were greater for ligamentogenic constructs. Ligamentogenic constructs had increased expression of the genes biglycan on day 7, decorin throughout the culture period, and Col1, tenomodulin, fibronectin, and tenascin-c on day 21; expression of Col1, tenomodulin, and tenascin-c increased between days 7 and 21. CONCLUSIONS AND CLINICAL RELEVANCE Ligamentogenic medium was superior to stromal medium for differentiation of ASCs to ligamentoblasts on suture-augmented Col1 scaffolds. Customized ligament neotissue may augment treatment options for dogs with cranial cruciate ligament rupture.
Collapse
Affiliation(s)
- Takashi Taguchi
- From the Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803
| | - Nan Zhang
- From the Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803
| | - Dominique Angibeau
- From the Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803
| | - Kathryn P Spivey
- From the Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803
| | - Mandi J Lopez
- From the Laboratory for Equine and Comparative Orthopedic Research, Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803
| |
Collapse
|
13
|
Quinlan JI, Franchi MV, Gharahdaghi N, Badiali F, Francis S, Hale A, Phillips BE, Szewczyk N, Greenhaff PL, Smith K, Maganaris C, Atherton PJ, Narici MV. Muscle and tendon adaptations to moderate load eccentric vs. concentric resistance exercise in young and older males. GeroScience 2021; 43:1567-1584. [PMID: 34196903 PMCID: PMC8492846 DOI: 10.1007/s11357-021-00396-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/27/2021] [Indexed: 02/07/2023] Open
Abstract
Resistance exercise training (RET) is well-known to counteract negative age-related changes in both muscle and tendon tissue. Traditional RET consists of both concentric (CON) and eccentric (ECC) contractions; nevertheless, isolated ECC contractions are metabolically less demanding and, thus, may be more suitable for older populations. However, whether submaximal (60% 1RM) CON or ECC contractions differ in their effectiveness is relatively unknown. Further, whether the time course of muscle and tendon adaptations differs to the above is also unknown. Therefore, this study aimed to establish the time course of muscle and tendon adaptations to submaximal CON and ECC RET. Twenty healthy young (24.5 ± 5.1 years) and 17 older males (68.1 ± 2.4 years) were randomly allocated to either isolated CON or ECC RET which took place 3/week for 8 weeks. Tendon biomechanical properties, muscle architecture and maximal voluntary contraction were assessed every 2 weeks and quadriceps muscle volume every 4 weeks. Positive changes in tendon Young's modulus were observed after 4 weeks in all groups after which adaptations in young males plateaued but continued to increase in older males, suggesting a dampened rate of adaptation with age. However, both CON and ECC resulted in similar overall changes in tendon Young's modulus, in all groups. Muscle hypertrophy and strength increases were similar between CON and ECC in all groups. However, pennation angle increases were greater in CON, and fascicle length changes were greater in ECC. Notably, muscle and tendon adaptations appeared to occur in synergy, presumably to maintain the efficacy of the muscle-tendon unit.
Collapse
Affiliation(s)
- Jonathan Iain Quinlan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,National Institute for Health Research, Birmingham Biomedical Research Centre At University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.,MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Martino Vladimiro Franchi
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK.,Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Nima Gharahdaghi
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Francesca Badiali
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Susan Francis
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Andrew Hale
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Bethan Eileen Phillips
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Nathaniel Szewczyk
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK.,Ohio Musculoskeletal and Neurological Institute (OMNI) and Department of Biomedical Sciences, Ohio University, Athens, OH, 43147, USA
| | - Paul Leonard Greenhaff
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Kenneth Smith
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | | | - Phillip James Atherton
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Marco Vincenzo Narici
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK. .,Department of Biomedical Sciences, University of Padova, Padova, Italy. .,CIR-MYO Myology Center, University of Padova, Padova, Italy.
| |
Collapse
|
14
|
Microscopic characterisation of local strain field in healing tissue in the central third defect of mouse patellar tendon at early-phase of healing. J Mech Behav Biomed Mater 2021; 123:104702. [PMID: 34365097 DOI: 10.1016/j.jmbbm.2021.104702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/26/2021] [Accepted: 07/03/2021] [Indexed: 11/20/2022]
Abstract
Tendons exhibit a hierarchical collagen structure, wherein higher-level components, such as collagen fibres and fascicles, are elongated, slid, and rotated during macroscopic stretching. These mechanical behaviours of collagen fibres play important roles in stimulating tenocytes, imposing stretching, compression, and shear deformation. It was hypothesised that a lack of local fibre behaviours in healing tendon tissue may result in a limited application of mechanical stimuli to cells within the tissue, leading to incomplete recovery of tissue structure and functions in regenerated tendons. Therefore, the present study aimed to measure the microscopic strain field in the healing tendon tissue. A central third defect was created in the patellar tendon of mice, and the regenerated tissue in the defect was examined by tensile testing, collagen fibre analysis, and local strain measurement using confocal microscopy at 3 and 6 weeks after surgery. Healing tissue at 3 weeks exhibited a significantly lower strength and disorganised collagen fibre structure compared with the normal tendon. These characteristics at 6 weeks remained significantly different from those of the normal tendon. Moreover, the magnitude of local shear strain in the healing tissue under 4% tissue strain was significantly smaller than that in the normal tendon. Differences in the local strain field may be reflected in the cell nuclear shape and possibly the amount of mechanical stimuli applied to the cells during tendon deformation. Accordingly, restoration of a normal local mechanical environment in the healing tissue may be key to a better healing outcome of tendon injury.
Collapse
|
15
|
|
16
|
Quantifying mechanical loading and elastic strain energy of the human Achilles tendon during walking and running. Sci Rep 2021; 11:5830. [PMID: 33712639 PMCID: PMC7955091 DOI: 10.1038/s41598-021-84847-w] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/19/2021] [Indexed: 01/31/2023] Open
Abstract
The purpose of the current study was to assess in vivo Achilles tendon (AT) mechanical loading and strain energy during locomotion. We measured AT length considering its curve-path shape. Eleven participants walked at 1.4 m/s and ran at 2.5 m/s and 3.5 m/s on a treadmill. The AT length was defined as the distance between its origin at the gastrocnemius medialis myotendinous junction (MTJ) and the calcaneal insertion. The MTJ was tracked using ultrasonography and projected to the reconstructed skin surface to account for its misalignment. Skin-to-bone displacements were assessed during a passive rotation (5°/s) of the ankle joint. Force and strain energy of the AT during locomotion were calculated by fitting a quadratic function to the experimentally measured tendon force-length curve obtained from maximum voluntary isometric contractions. The maximum AT strain and force were affected by speed (p < 0.05, ranging from 4.0 to 4.9% strain and 1.989 to 2.556 kN), yet insufficient in magnitude to be considered as an effective stimulus for tendon adaptation. Besides the important tendon energy recoil during the propulsion phase (7.8 to 11.3 J), we found a recoil of elastic strain energy at the beginning of the stance phase of running (70-77 ms after touch down) between 1.7 ± 0.6 and 1.9 ± 1.1 J, which might be functionally relevant for running efficiency.
Collapse
|
17
|
Merza E, Pearson S, Lichtwark G, Ollason M, Malliaras P. Immediate and long-term effects of mechanical loading on Achilles tendon volume: A systematic review and meta-analysis. J Biomech 2021; 118:110289. [PMID: 33556887 DOI: 10.1016/j.jbiomech.2021.110289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 01/14/2021] [Accepted: 01/23/2021] [Indexed: 01/07/2023]
Abstract
The Achilles tendon (AT) may experience changes in dimensions related to fluid flow under load. The extent to which fluid flow involves redistribution within or flow out of the tendon is not known and could be determined by investigating volume changes. This study aimed to synthesize data on immediate and long-term effects of loading on tendon volume among people with a healthy AT and midportion Achilles tendinopathy (MAT). A secondary aim was to synthesise data from the included studies investigating parallel change in cross-sectional area and length. Systematic electronic search was performed in MEDLINE, EMBASE, CINAHL, AMED, and Scopus from inception until May 2020. Standardized mean differences (SMDs) were calculated for intervention-induced changes from baseline for all outcomes. Methodological quality was assessed using modified version of Newcastle Ottawa Scale (NOS). Twelve studies were included in meta-analysis. For healthy AT, there were negligible to small changes in volume following cross-country running (-0.33 [95% CI = -1.11 to 0.45] (P = 0.41)) and isometric exercise (0.01 [95% CI = -0.54 to 0.55] (P = 0.98)) and a large increase at the short-term with 12-week isometric protocol (0.88 [95% CI = -0.10 to1.86] (P = 0.08)). For MAT, there was an immediate large reduction in volume with isometric exercise (-1.24 [95% CI = -1.93 to -0.55] (P = 0.0004)), small increase with eccentric exercise (0.41 [95% CI = -0.18 to 1.01](P = 0.18)) and small reduction at the short-term with long-term interventions (-0.46 [95% CI = -0.87 to -0.05] (P = 0.03)). This meta-analysis suggests that healthy AT remain isovolumetric with acute interventions while MAT exhibit immediate and short-term volume reductions in response to different interventions.
Collapse
Affiliation(s)
- Eman Merza
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston, Vic 3199, Melbourne, Australia.
| | - Stephen Pearson
- Centre for Health, Sport and Rehabilitation Sciences Research, University of Salford, Greater Manchester M5 4WT, United Kingdom.
| | - Glen Lichtwark
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St. Lucia, QLD 4072, Brisbane, Australia.
| | - Meg Ollason
- Department of Physiology, Biomedicine Discovery Institute, Monash University, Clayton, Vic 3800, Melbourne, Australia.
| | - Peter Malliaras
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Science, Monash University, Frankston, Vic 3199, Melbourne, Australia.
| |
Collapse
|
18
|
Siadat SM, Zamboulis DE, Thorpe CT, Ruberti JW, Connizzo BK. Tendon Extracellular Matrix Assembly, Maintenance and Dysregulation Throughout Life. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1348:45-103. [PMID: 34807415 DOI: 10.1007/978-3-030-80614-9_3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In his Lissner Award medal lecture in 2000, Stephen Cowin asked the question: "How is a tissue built?" It is not a new question, but it remains as relevant today as it did when it was asked 20 years ago. In fact, research on the organization and development of tissue structure has been a primary focus of tendon and ligament research for over two centuries. The tendon extracellular matrix (ECM) is critical to overall tissue function; it gives the tissue its unique mechanical properties, exhibiting complex non-linear responses, viscoelasticity and flow mechanisms, excellent energy storage and fatigue resistance. This matrix also creates a unique microenvironment for resident cells, allowing cells to maintain their phenotype and translate mechanical and chemical signals into biological responses. Importantly, this architecture is constantly remodeled by local cell populations in response to changing biochemical (systemic and local disease or injury) and mechanical (exercise, disuse, and overuse) stimuli. Here, we review the current understanding of matrix remodeling throughout life, focusing on formation and assembly during the postnatal period, maintenance and homeostasis during adulthood, and changes to homeostasis in natural aging. We also discuss advances in model systems and novel tools for studying collagen and non-collagenous matrix remodeling throughout life, and finally conclude by identifying key questions that have yet to be answered.
Collapse
Affiliation(s)
| | - Danae E Zamboulis
- Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
| | - Chavaunne T Thorpe
- Comparative Biomedical Sciences, The Royal Veterinary College, University of London, London, UK
| | - Jeffrey W Ruberti
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Brianne K Connizzo
- Department of Biomedical Engineering, Boston University, Boston, MA, USA.
| |
Collapse
|
19
|
Randelli F, Sartori P, Carlomagno C, Bedoni M, Menon A, Vezzoli E, Sommariva M, Gagliano N. The Collagen-Based Medical Device MD-Tissue Acts as a Mechanical Scaffold Influencing Morpho-Functional Properties of Cultured Human Tenocytes. Cells 2020; 9:cells9122641. [PMID: 33302563 PMCID: PMC7763591 DOI: 10.3390/cells9122641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 12/27/2022] Open
Abstract
Mechanotransduction is the ability of cells to translate mechanical stimuli into biochemical signals that can ultimately influence gene expression, cell morphology and cell fate. Tenocytes are responsible for tendon mechanical adaptation converting mechanical stimuli imposed during mechanical loading, thus affecting extracellular matrix homeostasis. Since we previously demonstrated that MD-Tissue, an injectable collagen-based medical compound containing swine-derived collagen as the main component, is able to affect tenocyte properties, the aim of this study was to analyze whether the effects triggered by MD-Tissue were based on mechanotransduction-related mechanisms. For this purpose, MD-Tissue was used to coat Petri dishes and cytochalasin B was used to deprive tenocytes of mechanical stimulation mediated by the actin cytoskeleton. Cell morphology, migration, collagen turnover pathways and the expression of key mechanosensors were analyzed by morphological and molecular methods. Our findings confirm that MD-Tissue affects collagen turnover pathways and favors cell migration and show that the MD-Tissue-induced effect represents a mechanical input involving the mechanotransduction machinery. Overall, MD-Tissue, acting as a mechanical scaffold, could represent an effective medical device for a novel therapeutic, regenerative and rehabilitative approach to favor tendon healing in tendinopathies.
Collapse
Affiliation(s)
- Filippo Randelli
- Hip Department (CAD) Gaetano Pini—CTO Orthopedic Institute, Università degli Studi di Milano, Piazza Cardinal Ferrari 1, 20122 Milan, Italy;
| | - Patrizia Sartori
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, 20133 Milan, Italy; (P.S.); (A.M.); (E.V.); (M.S.)
| | - Cristiano Carlomagno
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, via Capecelatro 66, 20148 Milan, Italy; (C.C.); (M.B.)
| | - Marzia Bedoni
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, via Capecelatro 66, 20148 Milan, Italy; (C.C.); (M.B.)
| | - Alessandra Menon
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, 20133 Milan, Italy; (P.S.); (A.M.); (E.V.); (M.S.)
- U.O.C. 1° Clinica Ortopedica, ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Piazza Cardinal Ferrari 1, 20122 Milan, Italy
| | - Elena Vezzoli
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, 20133 Milan, Italy; (P.S.); (A.M.); (E.V.); (M.S.)
| | - Michele Sommariva
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, 20133 Milan, Italy; (P.S.); (A.M.); (E.V.); (M.S.)
| | - Nicoletta Gagliano
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, 20133 Milan, Italy; (P.S.); (A.M.); (E.V.); (M.S.)
- Correspondence: ; Tel.: +39-02-50315374
| |
Collapse
|
20
|
Katugam K, Cox SM, Salzano MQ, De Boef A, Hast MW, Neuberger T, Ryan TM, Piazza SJ, Rubenson J. Altering the Mechanical Load Environment During Growth Does Not Affect Adult Achilles Tendon Properties in an Avian Bipedal Model. Front Bioeng Biotechnol 2020; 8:994. [PMID: 32984280 PMCID: PMC7492247 DOI: 10.3389/fbioe.2020.00994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 07/29/2020] [Indexed: 12/31/2022] Open
Abstract
Tendon mechanical properties respond to altered load in adults, but how load history during growth affects adult tendon properties remains unclear. To address this question, we adopted an avian model in which we altered the mechanical load environment across the growth span. Animals were divided at 2 weeks of age into three groups: (1) an exercise control group given the opportunity to perform high-acceleration movements (EXE, n = 8); (2) a sedentary group restricted from high-intensity exercise (RES, n = 8); and (3) a sedentary group also restricted from high-intensity exercise and in which the gastrocnemius muscles were partially paralyzed using repeated bouts of botulinum toxin-A injections (RES-BTX, n = 8). Video analysis of bird movement confirmed the restrictions eliminated high-intensity exercise and did not alter time spent walking and sitting between groups. At skeletal maturity (33–35 weeks) animals were sacrificed for analysis, consisting of high-field MRI and material load testing, of both the entire free Achilles tendon and the tendon at the bone-tendon junction. Free tendon stiffness, modulus, and hysteresis were unaffected by variation in load environment. Further, the bone-tendon junction cross-sectional area, stress, and strain were also unaffected by variations in load environment. These results suggest that: (a) a baseline level of low-intensity activity (standing and walking) may be sufficient to maintain tendon growth; and (b) if this lower threshold of tendon load is met, non-mechanical mediated tendon growth may override the load-induced mechanotransduction signal attributed to tendon remodeling in adults of the same species. These results are important for understanding of musculoskeletal function and tendon health in growing individuals.
Collapse
Affiliation(s)
- Kavya Katugam
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - Suzanne M Cox
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - Matthew Q Salzano
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States.,Integrative and Biomedical Physiology, The Pennsylvania State University, University Park, PA, United States.,Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Adam De Boef
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - Michael W Hast
- Biedermann Lab for Orthopaedic Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Thomas Neuberger
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States.,Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, United States
| | - Timothy M Ryan
- Department of Anthropology, The Pennsylvania State University, University Park, PA, United States
| | - Stephen J Piazza
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - Jonas Rubenson
- Biomechanics Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States.,Integrative and Biomedical Physiology, The Pennsylvania State University, University Park, PA, United States.,Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| |
Collapse
|
21
|
Citeroni MR, Ciardulli MC, Russo V, Della Porta G, Mauro A, El Khatib M, Di Mattia M, Galesso D, Barbera C, Forsyth NR, Maffulli N, Barboni B. In Vitro Innovation of Tendon Tissue Engineering Strategies. Int J Mol Sci 2020; 21:E6726. [PMID: 32937830 PMCID: PMC7555358 DOI: 10.3390/ijms21186726] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Abstract
Tendinopathy is the term used to refer to tendon disorders. Spontaneous adult tendon healing results in scar tissue formation and fibrosis with suboptimal biomechanical properties, often resulting in poor and painful mobility. The biomechanical properties of the tissue are negatively affected. Adult tendons have a limited natural healing capacity, and often respond poorly to current treatments that frequently are focused on exercise, drug delivery, and surgical procedures. Therefore, it is of great importance to identify key molecular and cellular processes involved in the progression of tendinopathies to develop effective therapeutic strategies and drive the tissue toward regeneration. To treat tendon diseases and support tendon regeneration, cell-based therapy as well as tissue engineering approaches are considered options, though none can yet be considered conclusive in their reproduction of a safe and successful long-term solution for full microarchitecture and biomechanical tissue recovery. In vitro differentiation techniques are not yet fully validated. This review aims to compare different available tendon in vitro differentiation strategies to clarify the state of art regarding the differentiation process.
Collapse
Affiliation(s)
- Maria Rita Citeroni
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| | - Maria Camilla Ciardulli
- Department of Medicine, Surgery and Dentistry, University of Salerno, Via S. Allende, 84081 Baronissi (SA), Italy; (M.C.C.); (G.D.P.); (N.M.)
| | - Valentina Russo
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| | - Giovanna Della Porta
- Department of Medicine, Surgery and Dentistry, University of Salerno, Via S. Allende, 84081 Baronissi (SA), Italy; (M.C.C.); (G.D.P.); (N.M.)
- Interdepartment Centre BIONAM, Università di Salerno, via Giovanni Paolo I, 84084 Fisciano (SA), Italy
| | - Annunziata Mauro
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| | - Mohammad El Khatib
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| | - Miriam Di Mattia
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| | - Devis Galesso
- Fidia Farmaceutici S.p.A., via Ponte della Fabbrica 3/A, 35031 Abano Terme (PD), Italy; (D.G.); (C.B.)
| | - Carlo Barbera
- Fidia Farmaceutici S.p.A., via Ponte della Fabbrica 3/A, 35031 Abano Terme (PD), Italy; (D.G.); (C.B.)
| | - Nicholas R. Forsyth
- Guy Hilton Research Centre, School of Pharmacy and Bioengineering, Keele University, Thornburrow Drive, Stoke on Trent ST4 7QB, UK;
| | - Nicola Maffulli
- Department of Medicine, Surgery and Dentistry, University of Salerno, Via S. Allende, 84081 Baronissi (SA), Italy; (M.C.C.); (G.D.P.); (N.M.)
- Department of Musculoskeletal Disorders, Faculty of Medicine and Surgery, University of Salerno, Via San Leonardo 1, 84131 Salerno, Italy
- Centre for Sports and Exercise Medicine, Barts and The London School of Medicine and Dentistry, Mile End Hospital, Queen Mary University of London, 275 Bancroft Road, London E1 4DG, UK
- School of Pharmacy and Bioengineering, Keele University School of Medicine, Thornburrow Drive, Stoke on Trent ST5 5BG, UK
| | - Barbara Barboni
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (V.R.); (A.M.); (M.E.K.); (M.D.M.); (B.B.)
| |
Collapse
|
22
|
Zitnay JL, Jung GS, Lin AH, Qin Z, Li Y, Yu SM, Buehler MJ, Weiss JA. Accumulation of collagen molecular unfolding is the mechanism of cyclic fatigue damage and failure in collagenous tissues. SCIENCE ADVANCES 2020; 6:eaba2795. [PMID: 32923623 PMCID: PMC7455178 DOI: 10.1126/sciadv.aba2795] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 07/14/2020] [Indexed: 05/04/2023]
Abstract
Overuse injuries to dense collagenous tissues are common, but their etiology is poorly understood. The predominant hypothesis that micro-damage accumulation exceeds the rate of biological repair is missing a mechanistic explanation. Here, we used collagen hybridizing peptides to measure collagen molecular damage during tendon cyclic fatigue loading and computational simulations to identify potential explanations for our findings. Our results revealed that triple-helical collagen denaturation accumulates with increasing cycles of fatigue loading, and damage is correlated with creep strain independent of the cyclic strain rate. Finite-element simulations demonstrated that biphasic fluid flow is a possible fascicle-level mechanism to explain the rate dependence of the number of cycles and time to failure. Molecular dynamics simulations demonstrated that triple-helical unfolding is rate dependent, revealing rate-dependent mechanisms at multiple length scales in the tissue. The accumulation of collagen molecular denaturation during cyclic loading provides a long-sought "micro-damage" mechanism for the development of overuse injuries.
Collapse
Affiliation(s)
- Jared L. Zitnay
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Gang Seob Jung
- Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Allen H. Lin
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Zhao Qin
- Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yang Li
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
| | - S. Michael Yu
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84132, USA
| | - Markus J. Buehler
- Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jeffrey A. Weiss
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84112, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT 84112, USA
- Department of Orthopaedics and School of Computing, University of Utah, Salt Lake City, UT 84112, USA
- Corresponding author.
| |
Collapse
|
23
|
Different Frequency of Cyclic Tensile Strain Relates to Anabolic/Catabolic Conditions Consistent with Immunohistochemical Staining Intensity in Tenocytes. Int J Mol Sci 2020; 21:ijms21031082. [PMID: 32041254 PMCID: PMC7037470 DOI: 10.3390/ijms21031082] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/24/2020] [Accepted: 02/02/2020] [Indexed: 01/13/2023] Open
Abstract
Tenocytes are mechanosensitive cells intimately adapting their expression profile and hence, their phenotype to their respective mechanomilieu. The immunolocalization and expression intensity of tenogenic, anabolic and catabolic markers in tenocytes in response to in vitro mechanical loading have not been monitored by immunohistochemical staining (IHC). Thus, we investigated the association between IHC intensities, different stimulation frequencies, and tenogenic metabolism using a versatile mechanical stretcher. Primary tenocytes obtained from murine Achilles tendons were transferred to poly(dimethylsiloxane) (PDMS) elastomeric chamber. Chambers were cyclically stretched by 5% in uniaxial direction at a variation of tensile frequency (1 or 2 Hz) for 3 h. After stretching, cell physiology, IHC intensities of tendon-related markers, and protein level of the angiogenesis marker vascular endothelial growth factor (VEGF) were evaluated. Cell proliferation in tenocytes stimulated with 1 Hz stretch was significantly higher than with 2 Hz or without stretch, while 2 Hz stretch induced significantly reduced cell viability and proliferation with microscopically detectable apoptotic cell changes. The amount of scleraxis translocated into the nuclei and tenomodulin immunoreactivity of tenocytes treated with stretch were significantly higher than of non-stretched cells. The collagen type-1 expression level in tenocytes stretched at 1 Hz was significantly higher than in those cultivated with 2 Hz or without stretching, whereas the matrix metalloproteinase (MMP)-1 and MMP-13 immunoreactivities of cells stretched at 2 Hz were significantly higher than in those stimulated with 1 Hz or without stretching. The secreted VEGF-protein level of tenocytes stretched at 2 Hz was significantly higher than without stretching. Our IHC findings consistent with cell physiology suggest that appropriate stretching can reproduce in vitro short-term tenogenic anabolic/catabolic conditions and allow us to identify an anabolic stretching profile.
Collapse
|
24
|
Wunderli SL, Blache U, Snedeker JG. Tendon explant models for physiologically relevant invitro study of tissue biology - a perspective. Connect Tissue Res 2020; 61:262-277. [PMID: 31931633 DOI: 10.1080/03008207.2019.1700962] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Background: Tendon disorders increasingly afflict our aging society but we lack the scientific understanding to clinically address them. Clinically relevant models of tendon disease are urgently needed as established small animal models of tendinopathy fail to capture essential aspects of the disease. Two-dimensional and three-dimensional cell and tissue culture models are similarly limited, lacking many physiological extracellular matrix cues required to maintain tissue homeostasis or guide matrix remodeling. These cues reflect the biochemical and biomechanical status of the tissue, and encode information regarding the mechanical and metabolic competence of the tissue. Tendon explants overcome some of these limitations and have thus emerged as a valuable tool for the discovery and study of mechanisms associated with tendon homeostasis and pathophysiology. Tendon explants retain native cell-cell and cell-matrix connections, while allowing highly reproducible experimental control over extrinsic factors like mechanical loading and nutritional availability. In this sense tendon explant models can deliver insights that are otherwise impossible to obtain from in vivo animal or in vitro cell culture models. Purpose: In this review, we aimed to provide an overview of tissue explant models used in tendon research, with a specific focus on the value of explant culture systems for the controlled study of the tendon core tissue. We discuss their advantages, limitations and potential future utility. We include suggestions and technical recommendations for the successful use of tendon explant cultures and conclude with an outlook on how explant models may be leveraged with state-of-the-art biotechnologies to propel our understanding of tendon physiology and pathology.
Collapse
Affiliation(s)
- Stefania L Wunderli
- University Hospital Balgrist, University of Zurich, Zurich, Switzerland.,Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Ulrich Blache
- University Hospital Balgrist, University of Zurich, Zurich, Switzerland.,Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Jess G Snedeker
- University Hospital Balgrist, University of Zurich, Zurich, Switzerland.,Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| |
Collapse
|
25
|
Abstract
Tendons link muscle to bone and transfer forces necessary for normal movement. Tendon injuries can be debilitating and their intrinsic healing potential is limited. These challenges have motivated the development of model systems to study the factors that regulate tendon formation and tendon injury. Recent advances in understanding of embryonic and postnatal tendon formation have inspired approaches that aimed to mimic key aspects of tendon development. Model systems have also been developed to explore factors that regulate tendon injury and healing. We highlight current model systems that explore developmentally inspired cellular, mechanical, and biochemical factors in tendon formation and tenogenic stem cell differentiation. Next, we discuss in vivo, in vitro, ex vivo, and computational models of tendon injury that examine how mechanical loading and biochemical factors contribute to tendon pathologies and healing. These tendon development and injury models show promise for identifying the factors guiding tendon formation and tendon pathologies, and will ultimately improve regenerative tissue engineering strategies and clinical outcomes.
Collapse
Affiliation(s)
- Sophia K Theodossiou
- Biological Engineering, University of Idaho, 875 Perimeter Dr. MS 0904, Moscow, ID 83844, USA
| | - Nathan R Schiele
- Biological Engineering, University of Idaho, 875 Perimeter Dr. MS 0904, Moscow, ID 83844, USA
| |
Collapse
|
26
|
Quinlan JI, Narici MV, Reeves ND, Franchi MV. Tendon Adaptations to Eccentric Exercise and the Implications for Older Adults. J Funct Morphol Kinesiol 2019; 4:E60. [PMID: 33467375 PMCID: PMC7739434 DOI: 10.3390/jfmk4030060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/14/2019] [Accepted: 08/19/2019] [Indexed: 12/12/2022] Open
Abstract
The purpose of this short review is to discuss the effects of eccentric exercise in modifying the properties of tendon tissue in healthy individuals. The tendon provides a mechanical link between muscle and bone, allowing force transmission to the skeleton, and thus, its properties have significant functional implications. Chronic resistance training has long been shown to increase the stiffness and Young's modulus of the tendon and even tendon cross-sectional area. However, as the tendon responds to the amount and/or frequency of strain, it has been previously suggested that eccentric training may result in greater adaptations due to the potential for greater training loads. Thus, this review discusses the effects of eccentric training upon healthy tendon tissue and compares these to other training modalities. Furthermore, it has been reported that the tendon may undergo adverse age-related changes. Thus, this review also discusses the potential application of eccentric resistance training as a preferential modality for counteracting these age-related changes. We conclude that while there may be no difference between contraction types for overall tendon adaptation, the lower demands of eccentric contractions may make it more appealing for the elderly population.
Collapse
Affiliation(s)
- Jonathan I Quinlan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham B15 2TT, UK
- NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham, NHS Foundation Trust and University of Birmingham, Birmingham B15 2GW, UK
| | - Marco V Narici
- Department of Biomedical Sciences, Institute of Physiology, University of Padua, 35131 Padua, Italy
| | - Neil D Reeves
- Department of Life Sciences, Research Centre for Musculoskeletal Science and Sports Medicine, Manchester Metropolitan University, Manchester M1 5GD, UK
| | - Martino V Franchi
- Department of Biomedical Sciences, Institute of Physiology, University of Padua, 35131 Padua, Italy
| |
Collapse
|
27
|
Udeze CP, Jones ER, Riley GP, Morrissey D, Screen HRC. An in vitro investigation into the effects of 10 Hz cyclic loading on tenocyte metabolism. Scand J Med Sci Sports 2019; 29:1511-1520. [PMID: 31102473 DOI: 10.1111/sms.13465] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 03/25/2019] [Accepted: 04/30/2019] [Indexed: 12/25/2022]
Abstract
Tendinopathy is a prevalent, highly debilitating condition, with poorly defined etiology. A wide range of clinical treatments has been proposed, with systematic reviews largely supporting shock wave therapy or eccentric exercise. Characterizing these treatments have demonstrated both generate perturbations within tendon at a frequency of approximately 8-12 Hz. Consequently, it is hypothesized that loading in this frequency range initiates increased anabolic tenocyte behavior, promoting tendon repair. The primary aim of this study was to investigate the effects of 10 Hz perturbations on tenocyte metabolism, comparing gene expression in response to a 10 Hz and 1 Hz loading profile. Tenocytes from healthy and tendinopathic human tendons were seeded into 3D collagen gels and subjected to 15 minutes cyclic strain at 10 Hz or 1 Hz. Tenocytes from healthy tendon showed increased expression of all analyzed genes in response to loading, with significantly increased expression of inflammatory and degradative genes with 10 Hz, relative to 1 Hz loading. By contrast, whilst the response of tenocytes from tendinopathy tendon also increased with 10 Hz loading, the overall response profile was more varied and less intense, possibly indicative of an altered healing response. Through inhibition of the pathway, IL1 was shown to be involved in the degradative and catabolic response of cells to high-frequency loading, abrogating the loading response. This study has demonstrated for the first time that loading at a frequency of 10 Hz may enhance the metabolic response of tenocytes by initiating an immediate degradatory and inflammatory cell response through the IL1 pathway, perhaps as an initial stage of tendon healing.
Collapse
Affiliation(s)
- Chineye P Udeze
- School of Engineering and Material Science, Queen Mary University of London, London, UK
| | | | | | - Dylan Morrissey
- Sport and Exercise Medicine, Queen Mary University of London, London, UK.,Physiotherapy Department, Bart's Health NHS Trust, London, UK
| | - Hazel R C Screen
- School of Engineering and Material Science, Queen Mary University of London, London, UK
| |
Collapse
|
28
|
Nakagawa Y, Lebaschi AH, Wada S, E. Green SJ, Wang D, Album ZM, Carballo CB, Deng XH, Rodeo SA. Duration of postoperative immobilization affects MMP activity at the healing graft-bone interface: Evaluation in a mouse ACL reconstruction model. J Orthop Res 2019; 37:325-334. [PMID: 30431170 PMCID: PMC6411439 DOI: 10.1002/jor.24177] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 10/22/2018] [Indexed: 02/04/2023]
Abstract
Excessive MMP activity may impair tendon-to-bone healing. However, little is known about the effect of joint motion on MMP activity after ACL reconstruction. The aim of this study was to determine the effect of different durations of knee immobilization on MMP activity in a mouse ACL reconstruction model using a fluorescent MMP probe which detects MMP 2, 3, 9, and 13 and near-infra red in vivo imaging. Sixty C57BL male mice underwent ACL reconstruction. Post-operatively, the animals were treated with free cage activity (Group 1), or with the use of an external fixator to restrict knee motion and weight bearing for 5 days (Group 2), 14 days (Group 3), and 28 days (Group 4). At days 3, 7, 16, 23, and 30, five mice underwent IVIS imaging. At days 3, 7, 16, and 30, histological analysis was also performed. Probe signal intensity in the whole limb peaked at day 7, followed by a decrease at day 16, and maintenance up to day 30. There was no significant difference among groups at any time point based on IVIS, but histologic localization of MMP probe signal showed significantly less activity in Group 2 and Group 3 compared to Group 4 in the bone tunnel at day 30. We demonstrated that short-term immobilization led to less MMP activity around the bone tunnel compared with prolonged immobilization. A short period of immobilization after ACL reconstruction might enhance graft-bone interface healing by mitigating excess MMP expression. These findings have implications for post-operative rehabilitation protocols following ACL reconstruction. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:325-334, 2019.
Collapse
Affiliation(s)
- Yusuke Nakagawa
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York,Department of Cartilage Regeneration, Tokyo Medical and Dental University, Tokyo, Japan
| | - Amir H. Lebaschi
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Susumu Wada
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Samuel J E. Green
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Dean Wang
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Zoe M. Album
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Camilla B. Carballo
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Xiang-Hua Deng
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| | - Scott A. Rodeo
- Laboratory for Joint Tissue Repair and Regeneration, Orthopaedic Soft Tissue Research, Hospital for Special Surgery, 535 East 70th Street, New York 10021, New York
| |
Collapse
|
29
|
Eriksen CS, Svensson RB, Gylling AT, Couppé C, Magnusson SP, Kjaer M. Load magnitude affects patellar tendon mechanical properties but not collagen or collagen cross-linking after long-term strength training in older adults. BMC Geriatr 2019; 19:30. [PMID: 30704412 PMCID: PMC6357404 DOI: 10.1186/s12877-019-1043-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 01/23/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Regular loading of tendons may counteract the negative effects of aging. However, the influence of strength training loading magnitude on tendon mechanical properties and its relation to matrix collagen content and collagen cross-linking is sparsely described in older adults. The purpose of the present study was to compare the effects of moderate or high load resistance training on tendon matrix and its mechanical properties. METHODS Seventeen women and 19 men, age 62-70 years, were recruited and randomly allocated to 12 months of heavy load resistance training (HRT), moderate load resistance training (MRT) or control (CON). Pre- and post-intervention testing comprised isometric quadriceps strength test (IsoMVC), ultrasound based testing of in vivo patellar tendon (PT) mechanical properties, MRI-based measurement of PT cross-sectional area (CSA), PT biopsies for assessment of fibril morphology, collagen content, enzymatic cross-links, and tendon fluorescence as a measure of advanced glycation end-products (AGEs). RESULTS Thirty three participants completed the intervention and were included in the data analysis. IsoMVC increased more after HRT (+ 21%) than MRT (+ 8%) and CON (+ 7%) (p < 0.05). Tendon stiffness (p < 0.05) and Young's modulus (p = 0.05) were also differently affected by training load with a reduction in CON and MRT but not in HRT. PT-CSA increased equally after both MRT and HRT. Collagen content, fibril morphology, enzymatic cross-links, and tendon fluorescence were unaffected by training. CONCLUSION Despite equal improvements in tendon size after moderate and heavy load resistance training, only heavy. load training seemed to maintain tendon mechanical properties in old age. The effect of load magnitude on tendon biomechanics was unrelated to changes of major load bearing matrix components in the tendon core. The study is a sub-study of the LISA study, which was registered at http://clinicaltrials.gov (NCT02123641) April 25th 2014.
Collapse
Affiliation(s)
- Christian S Eriksen
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark. .,Center for Healthy Aging, Department of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200, Copenhagen, N, Denmark.
| | - Rene B Svensson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark
| | - Anne T Gylling
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark.,Center for Healthy Aging, Department of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200, Copenhagen, N, Denmark
| | - Christian Couppé
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark.,Department of Physical and Occupational Therapy, Bispebjerg Hospital, Nielsine Nielsens Vej 11, DK-2400, Copenhagen, Denmark
| | - S Peter Magnusson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark.,Department of Physical and Occupational Therapy, Bispebjerg Hospital, Nielsine Nielsens Vej 11, DK-2400, Copenhagen, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Nielsine Nielsens Vej 11, building 8, 1st floor, DK-2400, Copenhagen, Denmark.,Center for Healthy Aging, Department of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200, Copenhagen, N, Denmark
| |
Collapse
|
30
|
Guzzoni V, Selistre-de-Araújo HS, Marqueti RDC. Tendon Remodeling in Response to Resistance Training, Anabolic Androgenic Steroids and Aging. Cells 2018; 7:E251. [PMID: 30544536 PMCID: PMC6316563 DOI: 10.3390/cells7120251] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 11/30/2018] [Accepted: 11/30/2018] [Indexed: 12/14/2022] Open
Abstract
Exercise training (ET), anabolic androgenic steroids (AAS), and aging are potential factors that affect tendon homeostasis, particularly extracellular matrix (ECM) remodeling. The goal of this review is to aggregate findings regarding the effects of resistance training (RT), AAS, and aging on tendon homeostasis. Data were gathered from our studies regarding the impact of RT, AAS, and aging on the calcaneal tendon (CT) of rats. We demonstrated a series of detrimental effects of AAS and aging on functional and biomechanical parameters, including the volume density of blood vessel cells, adipose tissue cells, tendon calcification, collagen content, the regulation of the major proteins related to the metabolic/development processes of tendons, and ECM remodeling. Conversely, RT seems to mitigate age-related tendon dysfunction. Our results suggest that AAS combined with high-intensity RT exert harmful effects on ECM remodeling, and also instigate molecular and biomechanical adaptations in the CT. Moreover, we provide further information regarding the harmful effects of AAS on tendons at a transcriptional level, and demonstrate the beneficial effects of RT against the age-induced tendon adaptations of rats. Our studies might contribute in terms of clinical approaches in favor of the benefits of ET against tendinopathy conditions, and provide a warning on the harmful effects of the misuse of AAS on tendon development.
Collapse
Affiliation(s)
- Vinicius Guzzoni
- Departamento de Biologia Molecular e Celular, Universidade Federal da Paraíba, João Pessoa 58051-970, Paraíba, Brazil.
| | | | - Rita de Cássia Marqueti
- Graduate Program of Rehabilitation Science, University of Brasilia, Distrito Federal, Brasília 70840-901, Distrito Federal, Brazil.
| |
Collapse
|
31
|
Effects of high loading by eccentric triceps surae training on Achilles tendon properties in humans. Eur J Appl Physiol 2018; 118:1725-1736. [DOI: 10.1007/s00421-018-3904-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/24/2018] [Indexed: 11/26/2022]
|
32
|
Wunderli SL, Widmer J, Amrein N, Foolen J, Silvan U, Leupin O, Snedeker JG. Minimal mechanical load and tissue culture conditions preserve native cell phenotype and morphology in tendon-a novel ex vivo mouse explant model. J Orthop Res 2018; 36:1383-1390. [PMID: 28980724 DOI: 10.1002/jor.23769] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 09/27/2017] [Indexed: 02/04/2023]
Abstract
Appropriate mechanical load is essential for tendon homeostasis and optimal tissue function. Due to technical challenges in achieving physiological mechanical loads in experimental tendon model systems, the research community still lacks well-characterized models of tissue homeostasis and physiological relevance. Toward this urgent goal, we present and characterize a novel ex vivo murine tail tendon explant model. Mouse tail tendon fascicles were extracted and cultured for 6 days in a load-deprived environment or in a custom-designed bioreactor applying low magnitude mechanical load (intermittent cycles to 1% strain, at 1 Hz) in serum-free tissue culture. Cells remained viable, as did collagen structure and mechanical properties in all tested conditions. Cell morphology in mechanically loaded tendon explants approximated native tendon, whereas load-deprived tendons lost their native cell morphology. These losses were reflected in altered gene expression, with mechanical loading tending to maintain tendon specific and matrix remodeling genes phenotypic of native tissue. We conclude from this study that ex vivo load deprivation of murine tendon in minimal culture medium results in a degenerative-like phenotype. We further conclude that onset of tissue degeneration can be suppressed by low-magnitude mechanical loading. Thus a minimal explant culture model featuring serum-free medium with low mechanical loads seems to provide a useful foundation for further investigations. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1383-1390, 2018.
Collapse
Affiliation(s)
- Stefania L Wunderli
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| | - Jonas Widmer
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| | - Niklaus Amrein
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| | - Jasper Foolen
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| | - Unai Silvan
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| | - Olivier Leupin
- Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland
| | - Jess G Snedeker
- University Hospital Balgrist, University of Zurich, Balgrist Campus, Lengghalde 5, Zürich, CH-8008, Switzerland.,Institute for Biomechanics, ETH Zurich, Switzerland
| |
Collapse
|
33
|
Mersmann F, Bohm S, Arampatzis A. Imbalances in the Development of Muscle and Tendon as Risk Factor for Tendinopathies in Youth Athletes: A Review of Current Evidence and Concepts of Prevention. Front Physiol 2017; 8:987. [PMID: 29249987 PMCID: PMC5717808 DOI: 10.3389/fphys.2017.00987] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/17/2017] [Indexed: 01/09/2023] Open
Abstract
Tendons feature the crucial role to transmit the forces exerted by the muscles to the skeleton. Thus, an increase of the force generating capacity of a muscle needs to go in line with a corresponding modulation of the mechanical properties of the associated tendon to avoid potential harm to the integrity of the tendinous tissue. However, as summarized in the present narrative review, muscle and tendon differ with regard to both the time course of adaptation to mechanical loading as well as the responsiveness to certain types of mechanical stimulation. Plyometric loading, for example, seems to be a more potent stimulus for muscle compared to tendon adaptation. In growing athletes, the increased levels of circulating sex hormones might additionally augment an imbalanced development of muscle strength and tendon mechanical properties, which could potentially relate to the increasing incidence of tendon overload injuries that has been indicated for adolescence. In fact, increased tendon stress and strain due to a non-uniform musculotendinous development has been observed recently in adolescent volleyball athletes, a high-risk group for tendinopathy. These findings highlight the importance to deepen the current understanding of the interaction of loading and maturation and demonstrate the need for the development of preventive strategies. Therefore, this review concludes with an evidence-based concept for a specific loading program for increasing tendon stiffness, which could be implemented in the training regimen of young athletes at risk for tendinopathy. This program incorporates five sets of four contractions with an intensity of 85–90% of the isometric voluntary maximum and a movement/contraction duration that provides 3 s of high magnitude tendon strain.
Collapse
Affiliation(s)
- Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
| |
Collapse
|
34
|
Snedeker JG, Foolen J. Tendon injury and repair - A perspective on the basic mechanisms of tendon disease and future clinical therapy. Acta Biomater 2017; 63:18-36. [PMID: 28867648 DOI: 10.1016/j.actbio.2017.08.032] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 08/16/2017] [Accepted: 08/25/2017] [Indexed: 12/16/2022]
Abstract
Tendon is an intricately organized connective tissue that efficiently transfers muscle force to the bony skeleton. Its structure, function, and physiology reflect the extreme, repetitive mechanical stresses that tendon tissues bear. These mechanical demands also lie beneath high clinical rates of tendon disorders, and present daunting challenges for clinical treatment of these ailments. This article aims to provide perspective on the most urgent frontiers of tendon research and therapeutic development. We start by broadly introducing essential elements of current understanding about tendon structure, function, physiology, damage, and repair. We then introduce and describe a novel paradigm explaining tendon disease progression from initial accumulation of damage in the tendon core to eventual vascular recruitment from the surrounding synovial tissues. We conclude with a perspective on the important role that biomaterials will play in translating research discoveries to the patient. STATEMENT OF SIGNIFICANCE Tendon and ligament problems represent the most frequent musculoskeletal complaints for which patients seek medical attention. Current therapeutic options for addressing tendon disorders are often ineffective, and the need for improved understanding of tendon physiology is urgent. This perspective article summarizes essential elements of our current knowledge on tendon structure, function, physiology, damage, and repair. It also describes a novel framework to understand tendon physiology and pathophysiology that may be useful in pushing the field forward.
Collapse
|
35
|
Waugh CM, Alktebi T, de Sa A, Scott A. Impact of rest duration on Achilles tendon structure and function following isometric training. Scand J Med Sci Sports 2017; 28:436-445. [PMID: 28603874 DOI: 10.1111/sms.12930] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/06/2017] [Indexed: 12/14/2022]
Abstract
Intervention programs are often sought to strengthen the Achilles tendon (AT) due to its high injury rate. Long rest periods between loading cycles have been found to increase collagen synthesis by tenocytes, suggesting rest duration may be important for tendon adaptation in vivo; however, exercise programs comparing long and short rest duration have not been directly compared. Fourteen adults completed a 12-week progressive training intervention; training sessions consisted of 5×10 isometric plantarflexion contractions each of 3-s duration performed at 90% of MVC three times weekly. Each leg was randomly allocated to long (LRT, 10-s rest) or short rest training (SRT, 3-s rest). We hypothesized that the leg allocated to LRT would demonstrate superior AT collagen organization compared to the leg receiving SRT, which would be related to improved biomechanical function. AT collagen organization and morphology were measured using ultrasound tissue characterization. AT properties were assessed before and after the intervention using a combination of dynamometry, ultrasound imaging, EMG, and motion capture. Contrary to our hypothesis, collagen organization did not improve following either training protocol; conversely, an unexpected decrease in echotype I proportion was seen after SRT (P<.001) but not LRT (P=.58), indicating an apparent protective effect of rest on collagen organization during isometric training. In contrast, AT adaptation was not appreciably enhanced by increasing intercycle rest duration; both protocols were equally effective at inducing significant strength gains and AT mechanical and material adaptation (P≤.001). Further research is necessary to identify optimal loading characteristics for injury prevention and rehabilitation.
Collapse
Affiliation(s)
- C M Waugh
- Faculty of Medicine, Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - T Alktebi
- Faculty of Medicine, Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - A de Sa
- Faculty of Medicine, Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - A Scott
- Faculty of Medicine, Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
36
|
Enhanced gap junction intercellular communication inhibits catabolic and pro-inflammatory responses in tenocytes against heat stress. J Cell Commun Signal 2017; 11:369-380. [PMID: 28601938 DOI: 10.1007/s12079-017-0397-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 05/28/2017] [Indexed: 12/17/2022] Open
Abstract
Elevation of tendon core temperature during severe activity is well known. However, its effects on tenocyte function have not been studied in detail. The present study tested a hypothesis that heat stimulation upregulates tenocyte catabolism, which can be modulated by the inhibition or the enhancement of gap junction intercellular communication (GJIC). Tenocytes isolated from rabbit Achilles tendons were subjected to heat stimulation at 37 °C, 41 °C or 43 °C for 30 min, and changes in cell viability, gene expressions and GJIC were examined. It was found that GJIC exhibited no changes by the stimulation even at 43 °C, but cell viability was decreased and catabolic and proinflammatory gene expressions were upregulated. Inhibition of GJIC demonstrated further upregulated catabolic and proinflammatory gene expressions. In contrast, enhanced GJIC, resulting from forced upregulation of connexin 43 gene, counteracted the heat-induced upregulation of catabolic and proinflammatory genes. These findings suggest that the temperature rise in tendon core could upregulate catabolic and proinflammatory activities, potentially leading to the onset of tendinopathy, and such upregulations could be suppressed by the enhancement of GJIC. Therefore, to prevent tendon injury at an early stage from becoming chronic injury, tendon core temperature and GJIC could be targets for post-activity treatments.
Collapse
|
37
|
Adekanmbi I, Zargar N, Hulley P. An in vitro scratch tendon tissue injury model: effects of high frequency low magnitude loading. Connect Tissue Res 2017; 58:162-171. [PMID: 27294971 DOI: 10.1080/03008207.2016.1198338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The healing process of ruptured tendons is suboptimal, taking months to achieve tissue with inferior properties to healthy tendon. Mechanical loading has been shown to positively influence tendon healing. However, high frequency low magnitude (HFLM) loads, which have shown promise in maintaining healthy tendon properties, have not been studied with in vitro injury models. Here, we present and validate an in vitro scratch tendon tissue injury model to investigate effects of HFLM loading on the properties of injured rat tail tendon fascicles (RTTFs). A longitudinal tendon tear was simulated using a needle aseptically to scratch a defined length along individual RTTFs. Tissue viability, biomechanical, and biochemical parameters were investigated before and 7 days after culture . The effects of static, HFLM (20 Hz), and low frequency (1 Hz) cyclic loading or no load were also investigated. Tendon viability was confirmed in damaged RTTFs after 7 days of culture, and the effects of a 0.77 ± 0.06 cm scratch on the mechanical property (tangent modulus) and tissue metabolism in damaged tendons were consistent, showing significant damage severity compared with intact tendons. Damaged tendon fascicles receiving HFLM (20 Hz) loads displayed significantly higher mean tangent modulus than unloaded damaged tendons (212.7 ± 14.94 v 92.7 ± 15.59 MPa), and damaged tendons receiving static loading (117.9 ± 10.65 MPa). HFLM stimulation maintained metabolic activity in 7-day cultured damaged tendons at similar levels to fresh tendons immediately following damage. Only damaged tendons receiving HFLM loads showed significantly higher metabolism than unloaded damaged tendons (relative fluorescence units -7021 ± 635.9 v 3745.1 ± 641.7). These validation data support the use of the custom-made in vitro injury model for investigating the potential of HFLM loading interventions in treating damaged tendons.
Collapse
Affiliation(s)
- Isaiah Adekanmbi
- a Institute of Biomedical Engineering, Department of Engineering Science , University of Oxford , Oxford , UK.,b Biomedical Engineering Division, School of Engineering , University of Glasgow , Glasgow , UK
| | - Nasim Zargar
- c Nuffield Department of Orthopaedics , Rheumatology and Musculoskeletal Sciences, University of Oxford , Oxford , UK
| | - Philippa Hulley
- c Nuffield Department of Orthopaedics , Rheumatology and Musculoskeletal Sciences, University of Oxford , Oxford , UK
| |
Collapse
|
38
|
Maeda E, Pian H, Ohashi T. Temporal regulation of gap junctional communication between tenocytes subjected to static tensile strain with physiological and non-physiological amplitudes. Biochem Biophys Res Commun 2017; 482:1170-1175. [DOI: 10.1016/j.bbrc.2016.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 12/02/2016] [Indexed: 01/28/2023]
|
39
|
Martin C, Sun W. Fatigue damage of collagenous tissues: experiment, modeling and simulation studies. J Long Term Eff Med Implants 2016; 25:55-73. [PMID: 25955007 DOI: 10.1615/jlongtermeffmedimplants.2015011749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Mechanical fatigue damage is a critical issue for soft tissues and tissue-derived materials, particularly for musculoskeletal and cardiovascular applications; yet, our understanding of the fatigue damage process is incomplete. Soft tissue fatigue experiments are often difficult and time-consuming to perform, which has hindered progress in this area. However, the recent development of soft-tissue fatigue-damage constitutive models has enabled simulation-based fatigue analyses of tissues under various conditions. Computational simulations facilitate highly controlled and quantitative analyses to study the distinct effects of various loading conditions and design features on tissue durability; thus, they are advantageous over complex fatigue experiments. Although significant work to calibrate the constitutive models from fatigue experiments and to validate predictability remains, further development in these areas will add to our knowledge of soft-tissue fatigue damage and will facilitate the design of durable treatments and devices. In this review, the experimental, modeling, and simulation efforts to study collagenous tissue fatigue damage are summarized and critically assessed.
Collapse
Affiliation(s)
- Caitlin Martin
- Tissue Mechanics Laboratory, The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30313
| | - Wei Sun
- Tissue Mechanics Laboratory, The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30313
| |
Collapse
|
40
|
Huisman E, Lu A, Jamil S, Mousavizadeh R, McCormack R, Roberts C, Scott A. Influence of repetitive mechanical loading on MMP2 activity in tendon fibroblasts. J Orthop Res 2016; 34:1991-2000. [PMID: 26909661 DOI: 10.1002/jor.23207] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Accepted: 02/18/2016] [Indexed: 02/04/2023]
Abstract
Matrix metalloproteinase2 has been implicated in tendon pathology caused by repetitive movements. However, its activity in the early stages of the tendon's response to overuse, and its presence in the circulation as a possible indicator of tendon degradation, remain unknown. Human tendon cells were repetitively stretched for 5 days, and the rabbit Achilles tendon complex underwent repetitive motion 3× per week for 2 weeks. Quantitative polymer chain reaction analysis was performed to detect matrix metalloproteinase2/14 and tissue inhibitor of matrix metalloproteinase2 messenger ribonucleic acid of cells and rabbit tissue, and matrix metalloproteinase2 protein levels were determined with an enzyme linked immunoassay. Matrix metalloproteinase2 activity was examined using zymography of the conditioned media, tendon and serum. Immunohistochemistry was used to localize matrix metalloproteinase2 in tendon tissue, and the density of fibrillar collagen in tendons was examined using second harmonic generation microscopy. Tendon cells stretched with high strain or high frequency demonstrated increased matrix metalloproteinase2 messenger ribonucleic acid and protein levels. Matrix metalloproteinase2 activity was increased in the rabbit Achilles tendon tissue at weeks 1 and 2; however, serum activity was only increased at week 1. After 2 weeks of exercise, the collagen density was lower in specific regions of the exercised rabbit Achilles tendon complex. Matrix metalloproteinase2 expression in exercised rabbit Achilles tendons was detected surrounding tendon fibroblasts. Repetitive mechanical stimulation of tendon cells results in a small increase in matrix metalloproteinase2 levels, but it appears unlikely that serum matrix metalloproteinase2 will be a useful indicator of tendon overuse injury. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1991-2000, 2016.
Collapse
Affiliation(s)
- Elise Huisman
- Department of Physical Therapy, University of British Columbia, Vancouver, Canada.,Centre for Hip Health and Mobility, Vancouver Coastal Health and Research Institute, Vancouver, Canada
| | - Alex Lu
- Department of Physical Therapy, University of British Columbia, Vancouver, Canada.,Centre for Hip Health and Mobility, Vancouver Coastal Health and Research Institute, Vancouver, Canada
| | - Sarwat Jamil
- Centre for Hip Health and Mobility, Vancouver Coastal Health and Research Institute, Vancouver, Canada
| | - Rouhollah Mousavizadeh
- Centre for Hip Health and Mobility, Vancouver Coastal Health and Research Institute, Vancouver, Canada
| | - Robert McCormack
- Department of Orthopaedic Surgery, University of British Columbia, Vancouver, Canada
| | - Clive Roberts
- Department of Dentistry, University of British Columbia, Vancouver, Canada
| | - Alex Scott
- Department of Physical Therapy, University of British Columbia, Vancouver, Canada.,Centre for Hip Health and Mobility, Vancouver Coastal Health and Research Institute, Vancouver, Canada
| |
Collapse
|
41
|
Cell Signaling in Tenocytes: Response to Load and Ligands in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 920:79-95. [DOI: 10.1007/978-3-319-33943-6_7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
42
|
Engineering Tendon: Scaffolds, Bioreactors, and Models of Regeneration. Stem Cells Int 2015; 2016:3919030. [PMID: 26839559 PMCID: PMC4709784 DOI: 10.1155/2016/3919030] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 09/20/2015] [Indexed: 12/23/2022] Open
Abstract
Tendons bridge muscle and bone, translating forces to the skeleton and increasing the safety and efficiency of locomotion. When tendons fail or degenerate, there are no effective pharmacological interventions. The lack of available options to treat damaged tendons has created a need to better understand and improve the repair process, particularly when suitable autologous donor tissue is unavailable for transplantation. Cells within tendon dynamically react to loading conditions and undergo phenotypic changes in response to mechanobiological stimuli. Tenocytes respond to ultrastructural topography and mechanical deformation via a complex set of behaviors involving force-sensitive membrane receptor activity, changes in cytoskeletal contractility, and transcriptional regulation. Effective ex vivo model systems are needed to emulate the native environment of a tissue and to translate cell-matrix forces with high fidelity. While early bioreactor designs have greatly expanded our knowledge of mechanotransduction, traditional scaffolds do not fully model the topography, composition, and mechanical properties of native tendon. Decellularized tendon is an ideal scaffold for cultivating replacement tissue and modeling tendon regeneration. Decellularized tendon scaffolds (DTS) possess high clinical relevance, faithfully translate forces to the cellular scale, and have bulk material properties that match natural tissue. This review summarizes progress in tendon tissue engineering, with a focus on DTS and bioreactor systems.
Collapse
|
43
|
Abstract
Synopsis Tendinopathy is a very common disorder in both recreational and elite athletes. Many individuals have recurrent symptoms that lead to chronic conditions and termination of sports activity. Exercise has become a popular and somewhat efficacious treatment regime, and isolated eccentric exercise has been particularly promoted. In this clinical commentary, we review the relevant evidence for different exercise regimes in tendinopathy rehabilitation, with particular focus on the applied loads that are experienced by the tendon and how the exercise regime may affect these applied loads. There is no convincing clinical evidence to demonstrate that isolated eccentric loading exercise improves clinical outcomes more than other loading therapies. However, the great variation and sometimes insufficient reporting of the details of treatment protocols may hamper the interpretation of what may be the optimal exercise regime with respect to parameters such as load magnitude, speed of movement, and recovery period between exercise sessions. Future studies should control for these loading parameters, evaluate various exercise dosages, and think beyond isolated eccentric exercises to arrive at firm recommendations regarding rehabilitation of individuals with tendinopathies. J Orthop Sports Phys Ther 2015;45(11):853-863. Epub 14 Oct 2015. doi:10.2519/jospt.2015.5910.
Collapse
|
44
|
Lavagnino M, Wall ME, Little D, Banes AJ, Guilak F, Arnoczky SP. Tendon mechanobiology: Current knowledge and future research opportunities. J Orthop Res 2015; 33:813-22. [PMID: 25763779 PMCID: PMC4524513 DOI: 10.1002/jor.22871] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 02/13/2015] [Indexed: 02/04/2023]
Abstract
Tendons mainly function as load-bearing tissues in the muscloskeletal system; transmitting loads from muscle to bone. Tendons are dynamic structures that respond to the magnitude, direction, frequency, and duration of physiologic as well as pathologic mechanical loads via complex interactions between cellular pathways and the highly specialized extracellular matrix. This paper reviews the evolution and current knowledge of mechanobiology in tendon development, homeostasis, disease, and repair. In addition, we review several novel mechanotransduction pathways that have been identified recently in other tissues and cell types, providing potential research opportunities in the field of tendon mechanobiology. We also highlight current methods, models, and technologies being used in a wide variety of mechanobiology research that could be investigated in the context of their potential applicability for answering some of the fundamental unanswered questions in this field. The article concludes with a review of the major questions and future goals discussed during the recent ORS/ISMMS New Frontiers in Tendon Research Conference held on September 10 and 11, 2014 in New York City.
Collapse
Affiliation(s)
- Michael Lavagnino
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine Michigan State University, East Lansing, Michigan
| | | | | | | | | | | |
Collapse
|
45
|
Gaspar D, Spanoudes K, Holladay C, Pandit A, Zeugolis D. Progress in cell-based therapies for tendon repair. Adv Drug Deliv Rev 2015; 84:240-56. [PMID: 25543005 DOI: 10.1016/j.addr.2014.11.023] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 11/08/2014] [Accepted: 11/12/2014] [Indexed: 02/07/2023]
Abstract
The last decade has seen significant developments in cell therapies, based on permanently differentiated, reprogrammed or engineered stem cells, for tendon injuries and degenerative conditions. In vitro studies assess the influence of biophysical, biochemical and biological signals on tenogenic phenotype maintenance and/or differentiation towards tenogenic lineage. However, the ideal culture environment has yet to be identified due to the lack of standardised experimental setup and readout system. Bone marrow mesenchymal stem cells and tenocytes/dermal fibroblasts appear to be the cell populations of choice for clinical translation in equine and human patients respectively based on circumstantial, rather than on hard evidence. Collaborative, inter- and multi-disciplinary efforts are expected to provide clinically relevant and commercially viable cell-based therapies for tendon repair and regeneration in the years to come.
Collapse
Affiliation(s)
- Diana Gaspar
- Network of Excellence for Functional Biomaterials (NFB), National University of Ireland, Galway (NUI Galway), Galway, Ireland
| | - Kyriakos Spanoudes
- Network of Excellence for Functional Biomaterials (NFB), National University of Ireland, Galway (NUI Galway), Galway, Ireland
| | - Carolyn Holladay
- Network of Excellence for Functional Biomaterials (NFB), National University of Ireland, Galway (NUI Galway), Galway, Ireland
| | - Abhay Pandit
- Network of Excellence for Functional Biomaterials (NFB), National University of Ireland, Galway (NUI Galway), Galway, Ireland
| | - Dimitrios Zeugolis
- Network of Excellence for Functional Biomaterials (NFB), National University of Ireland, Galway (NUI Galway), Galway, Ireland.
| |
Collapse
|
46
|
Bohm S, Mersmann F, Arampatzis A. Human tendon adaptation in response to mechanical loading: a systematic review and meta-analysis of exercise intervention studies on healthy adults. SPORTS MEDICINE-OPEN 2015; 1:7. [PMID: 27747846 PMCID: PMC4532714 DOI: 10.1186/s40798-015-0009-9] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 01/29/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND The present article systematically reviews recent literature on the in vivo adaptation of asymptomatic human tendons following increased chronic mechanical loading, and meta-analyzes the loading conditions, intervention outcomes, as well as methodological aspects. METHODS The search was performed in the databases PubMed, Web of Knowledge, and Scopus as well as in the reference lists of the eligible articles. A study was included if it conducted (a) a longitudinal exercise intervention (≥8 weeks) on (b) healthy humans (18 to 50 years), (c) investigating the effects on mechanical (i.e., stiffness), material (i.e., Young's modulus) and/or morphological properties (i.e., cross-sectional area (CSA)) of tendons in vivo, and was reported (d) in English language. Weighted average effect sizes (SMD, random-effects) and heterogeneity (Q and I 2 statistics) of the intervention-induced changes of tendon stiffness, Young's modulus, and CSA were calculated. A subgroup analysis was conducted regarding the applied loading intensity, muscle contraction type, and intervention duration. Further, the methodological study quality and the risk of bias were assessed. RESULTS The review process yielded 27 studies with 37 separate interventions on either the Achilles or patellar tendon (264 participants). SMD was 0.70 (confidence interval: 0.51, 0.88) for tendon stiffness (N=37), 0.69 (0.36, 1.03) for Young's modulus (N=17), and 0.24 (0.07, 0.42) for CSA (N=33), with significant overall intervention effects (p<0.05). The heterogeneity analysis (stiffness: I 2 =30%; Young's modulus: I 2 =57%; CSA: I 2 =21%) indicated that differences in the loading conditions may affect the adaptive responses. The subgroup analysis confirmed that stiffness adaptation significantly (p<0.05) depends on loading intensity (I 2 =0%), but not on muscle contraction type. Although not significantly different, SMD was higher for interventions with longer duration (≥12 weeks). The average score of 71±9% in methodological quality assessment indicated an appropriate quality of most studies. CONCLUSIONS The present meta-analysis provides elaborate statistical evidence that tendons are highly responsive to diverse loading regimens. However, the data strongly suggests that loading magnitude in particular plays a key role for tendon adaptation in contrast to muscle contraction type. Furthermore, intervention-induced changes in tendon stiffness seem to be more attributed to adaptations of the material rather than morphological properties.
Collapse
Affiliation(s)
- Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Philippstr. 13, Haus 11, 10115, Berlin, Germany
| | - Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Philippstr. 13, Haus 11, 10115, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Philippstr. 13, Haus 11, 10115, Berlin, Germany.
| |
Collapse
|
47
|
Tozzi P. A unifying neuro-fasciagenic model of somatic dysfunction - Underlying mechanisms and treatment - Part II. J Bodyw Mov Ther 2015; 19:526-43. [PMID: 26118526 DOI: 10.1016/j.jbmt.2015.03.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 02/20/2015] [Accepted: 02/24/2015] [Indexed: 02/07/2023]
Abstract
This paper offers an extensive review of the main fascia-mediated mechanisms underlying various therapeutic processes of clinical relevance for manual therapy. The concept of somatic dysfunction is revisited in light of the several fascial influences that may come into play during and after manual treatment. A change in perspective is thus proposed: from a nociceptive model that for decades has viewed somatic dysfunction as a neurologically-mediated phenomenon, to a unifying neuro-fascial model that integrates neural influences into a multifactorial and multidimensional interpretation of manual therapeutic effects as being partially, if not entirely, mediated by the fascia. By taking into consideration a wide spectrum of fascia-related factors - from cell-based mechanisms to cognitive and behavioural influences - a model emerges suggesting, amongst other results, a multidisciplinary-approach to the intervention of somatic dysfunction. Finally, it is proposed that a sixth osteopathic 'meta-model' - the connective tissue-fascial model - be added to the existing five models in osteopathic philosophy as the main interface between all body systems, thus providing a structural and functional framework for the body's homoeostatic potential and its inherent abilities to heal.
Collapse
Affiliation(s)
- Paolo Tozzi
- School of Osteopathy C.R.O.M.O.N., Rome, Italy; C.O.ME. Collaboration, Pescara, Italy.
| |
Collapse
|
48
|
Huisman E, Lu A, McCormack RG, Scott A. Enhanced collagen type I synthesis by human tenocytes subjected to periodic in vitro mechanical stimulation. BMC Musculoskelet Disord 2014; 15:386. [PMID: 25414072 PMCID: PMC4256895 DOI: 10.1186/1471-2474-15-386] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 11/06/2014] [Indexed: 11/10/2022] Open
Abstract
Background Mechanical stimulation (e.g. slow heavy loading) has proven beneficial in the rehabilitation of chronic tendinopathy, however the optimal parameters of stimulation have not been experimentally determined. In this study of mechanically stimulated human tenocytes, the influence of rest insertion and cycle number on (1) the protein and mRNA levels of type I and III collagen; (2) the mRNA levels of transforming growth factor beta (TGFB1) and scleraxis (SCXA); and (3) tenocyte morphology, were assessed. Methods Human hamstring tenocytes were mechanically stimulated using a Flexcell® system. The stimulation regimens were 1) continuous and 2) rest-inserted cyclic equiaxial strain at a frequency of 0.1 Hz for 100 or 1000 cycles. Data were normalized to unstimulated (non-stretched) control groups for every experimental condition. qPCR was performed to determine relative mRNA levels and quantitative immunocytochemistry image analysis was used to assess protein levels and cell morphology. Results Collagen type I mRNA level and pro-collagen protein levels were higher in tenocytes that were subjected to rest-inserted mechanical stimulation, compared to continuous stretching (p < 0.05). Rest insertion and increased cycle number also had significant positive effects on the levels of mRNA for TGFB1 and SCXA (p < 0.05). There was no direct relation between cell morphology and gene expression, however mechanical stimulation, overall, induced a metabolically active tenocyte phenotype as evidenced by cells that on average demonstrated a decreased major-minor axis ratio (p < 0.05) with greater branching (p < 0.01). Conclusions The incorporation of rest periods in a mechanical stretching regimen results in greater collagen type I synthesis. This knowledge may be beneficial in refining rehabilitation protocols for tendon injury. Electronic supplementary material The online version of this article (doi:10.1186/1471-2474-15-386) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | - Alex Scott
- Department of Physical Therapy, University of British Columbia, Vancouver, Canada.
| |
Collapse
|
49
|
Bohm S, Mersmann F, Tettke M, Kraft M, Arampatzis A. Human Achilles tendon plasticity in response to cyclic strain: effect of rate and duration. ACTA ACUST UNITED AC 2014; 217:4010-7. [PMID: 25267851 DOI: 10.1242/jeb.112268] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
High strain magnitude and low strain frequency are important stimuli for tendon adaptation. Increasing the rate and duration of the applied strain may enhance the adaptive responses. Therefore, our purpose was to investigate the effect of strain rate and duration on Achilles tendon adaptation. The study included two experimental groups (N=14 and N=12) and a control group (N=13). The participants of the experimental groups exercised according to a reference protocol (14 weeks, four times a week), featuring a high strain magnitude (~6.5%) and a low strain frequency (0.17 Hz, 3 s loading/3 s relaxation) on one leg and with either a higher strain rate (one-legged jumps) or a longer strain duration (12 s loading) on the other leg. The strain magnitude and loading volume were similar in all protocols. Before and after the interventions, the tendon stiffness, Young's modulus and cross-sectional area were examined using magnetic resonance imaging, ultrasound and dynamometry. The reference and long strain duration protocols induced significantly increased (P<0.05) tendon stiffness (57% and 25%), cross-sectional area (4.2% and 5.3%) and Young's modulus (51% and 17%). The increases in tendon stiffness and Young's modulus were higher in the reference protocol. Although region-specific tendon hypertrophy was also detected after the high strain rate training, there was only a tendency of increased stiffness (P=0.08) and cross-sectional area (P=0.09). The control group did not show any changes (P=0.86). The results provide evidence that a high strain magnitude, an appropriate strain duration and repetitive loading are essential components for an efficient adaptive stimulus for tendons.
Collapse
Affiliation(s)
- Sebastian Bohm
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
| | - Falk Mersmann
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
| | - Martin Tettke
- Technische Universität Berlin, Department of Medical Technology, 10587 Berlin, Germany
| | - Marc Kraft
- Technische Universität Berlin, Department of Medical Technology, 10587 Berlin, Germany
| | - Adamantios Arampatzis
- Humboldt-Universität zu Berlin, Department of Training and Movement Sciences, 10115 Berlin, Germany
| |
Collapse
|
50
|
Shepherd JH, Riley GP, Screen HRC. Early stage fatigue damage occurs in bovine tendon fascicles in the absence of changes in mechanics at either the gross or micro-structural level. J Mech Behav Biomed Mater 2014; 38:163-72. [PMID: 25001495 PMCID: PMC4148183 DOI: 10.1016/j.jmbbm.2014.06.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/01/2014] [Accepted: 06/04/2014] [Indexed: 12/04/2022]
Abstract
Many tendon injuries are believed to result from repetitive motion or overuse, leading to the accumulation of micro-damage over time. In vitro fatigue loading can be used to characterise damage during repeated use and investigate how this may relate to the aetiology of tendinopathy. This study considered the effect of fatigue loading on fascicles from two functionally distinct bovine tendons: the digital extensor and deep digital flexor. Micro-scale extension mechanisms were investigated in fascicles before or after a period of cyclic creep loading, comparing two different measurement techniques – the displacement of a photo-bleached grid and the use of nuclei as fiducial markers. Whilst visual damage was clearly identified after only 300 cycles of creep loading, these visual changes did not affect either gross fascicle mechanics or fascicle microstructural extension mechanisms over the 900 fatigue cycles investigated. However, significantly greater fibre sliding was measured when observing grid deformation rather than the analysis of nuclei movement. Measurement of microstructural extension with both techniques was localised and this may explain the absence of change in microstructural deformation in response to fatigue loading. Alternatively, the data may demonstrate that fascicles can withstand a degree of matrix disruption with no impact on mechanics. Whilst use of a photo-bleached grid to directly measure the collagen is the best indicator of matrix deformation, nuclei tracking may provide a better measure of the strain perceived directly by the cells. Tendon fascicle gross mechanics and micro-scale deformation investigated after fatigue loading. Fascicles can withstand a degree of matrix disruption without impact on mechanics. More fibre sliding was observed measuring grid deformation than tracking nuclei. Nuclei tracking may better represent the strains experienced by cells than grid deformation.
Collapse
Affiliation(s)
- Jennifer H Shepherd
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary, University of London, Mile End Road, E1 4NS, UK
| | - Graham P Riley
- School of Biological Sciences, University of East Anglia, UK
| | - Hazel R C Screen
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary, University of London, Mile End Road, E1 4NS, UK.
| |
Collapse
|