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Kara M, Kara Ö, Durmuş ME, Analay P, Şener FE, Çıtır BN, Korkmaz GO, Ünlü Z, Tiftik T, Gürçay E, Mülkoğlu C, Yalçınkaya B, Bağcıer F, Aksakal MF, Erdoğan K, Sertçelik A, Çakır B, Kaymak B, Özçakar L. The Relationship Among Probable SARCopenia, Osteoporosis and SuprasPinatus Tendon Tears in Postmenopausal Women: The SARCOSP Study. Calcif Tissue Int 2024; 114:340-347. [PMID: 38342790 PMCID: PMC10957602 DOI: 10.1007/s00223-024-01183-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/05/2024] [Indexed: 02/13/2024]
Abstract
We aimed to investigate the relationship among probable sarcopenia, osteoporosis (OP) and supraspinatus tendon (SSP) tears in postmenopausal women. Postmenopausal women screened/followed for OP were recruited. Demographic data, comorbidities, exercise/smoking status, and handgrip strength values were recorded. Probable sarcopenia was diagnosed as handgrip strength values < 20 kg. Achilles and SSP thicknesses were measured using ultrasound. Among 1443 postmenopausal women, 268 (18.6%) subjects had SSP tears. Unilateral tears were on the dominant side in 146 (10.1%) and on the non-dominant side in 55 women (3.8%). In contrast to those without, women with SSP tears had older age, lower level of education, thinner SSP and lower grip strength (all p < 0.05). In addition, they had higher frequencies of hypertension, hyperlipidemia, DM, OP and probable sarcopenia, but lower exercise frequency (all p < 0.05). Binary logistic regression modeling revealed that age [odds ratio (OR): 1.046 (1.024-1.067 95% CI)], hypertension [OR: 1.560 (1.145-2.124 95% CI)], OP [OR: 1.371 (1.022-1.839 95% CI)] and probable sarcopenia [OR: 1.386 (1.031-1.861 95% CI)] were significant predictors for SSP tears (all p < 0.05). This study showed that age, presence of hypertension, probable sarcopenia and OP were related with SSP tears in postmenopausal women. To this end, although OP appeared to be related to SSP tears, SSP tear/thickness evaluation can be recommended for OP patients, especially those who have other risk factors such as older age, higher BMI, hypertension, and probable sarcopenia.
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Affiliation(s)
- Murat Kara
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
| | - Özgür Kara
- Department of Physical Medicine and Rehabilitation, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, Turkey
| | - Mahmut Esad Durmuş
- Department of Physical Medicine and Rehabilitation, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, Turkey
| | - Pelin Analay
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey.
| | - Fatıma Edibe Şener
- Department of Physical Medicine and Rehabilitation, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, Turkey
| | - Beyza Nur Çıtır
- Department of Physical Medicine and Rehabilitation, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, Turkey
| | - Gizem Olgu Korkmaz
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
| | - Zeliha Ünlü
- Department of Physical Medicine and Rehabilitation, Celal Bayar University, Manisa, Turkey
| | - Tülay Tiftik
- Department of Physical Medicine and Rehabilitation, Ankara Training and Research Hospital, Ankara, Turkey
| | - Eda Gürçay
- Department of Physical Medicine and Rehabilitation, University of Health Sciences, Gaziler Physical Medicine and Rehabilitation Education and Research Hospital, Ankara, Turkey
| | - Cevriye Mülkoğlu
- Department of Physical Medicine and Rehabilitation, Ankara Training and Research Hospital, Ankara, Turkey
| | - Berkay Yalçınkaya
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
| | - Fatih Bağcıer
- Department of Physical Medicine and Rehabilitation, Basaksehir Cam Sakura Hospital, Istanbul, Turkey
| | - Mahmud Fazıl Aksakal
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
| | - Kübra Erdoğan
- Department of Physical Medicine and Rehabilitation, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, Turkey
| | - Ahmet Sertçelik
- Department of Public Health, Division of Epidemiology, Hacettepe University Medical School, Ankara, Turkey
| | - Banu Çakır
- Department of Public Health, Division of Epidemiology, Hacettepe University Medical School, Ankara, Turkey
| | - Bayram Kaymak
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
| | - Levent Özçakar
- Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey
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Cramer A, Højfeldt G, Schjerling P, Agergaard J, van Hall G, Olsen J, Hölmich P, Kjaer M, Barfod KW. Achilles Tendon Tissue Turnover Before and Immediately After an Acute Rupture. Am J Sports Med 2023; 51:2396-2403. [PMID: 37313851 DOI: 10.1177/03635465231177890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
BACKGROUND An Achilles tendon rupture (ATR) is a frequent injury and results in the activation of tendon cells and collagen expression, but it is unknown to what extent turnover of the tendon matrix is altered before or after a rupture. PURPOSE/HYPOTHESIS The purpose of this study was to characterize tendon tissue turnover before and immediately after an acute rupture in patients. It was hypothesized that a rupture would result in pronounced collagen synthesis in the early phase (first 2 weeks) after the injury. STUDY DESIGN Cross-sectional study; Level of evidence, 3. METHODS The study included patients (N = 18) eligible for surgery after an ATR. At the time of inclusion, the patients ingested deuterium oxide (2H2O) orally, and on the day of surgery (within 14 days of the injury), they received a 3-hour flood-primed infusion of an 15N-proline tracer. During surgery, the patients had 1 biopsy specimen taken from the ruptured part of the Achilles tendon and 1 that was 3 to 5 cm proximal to the rupture as a control. The biopsy specimens were analyzed for carbon-14 (14C) levels in the tissue to calculate long-term turnover (years), incorporation of 2H-alanine (from 2H2O) into the tissue to calculate the fractional synthesis rate (FSR) of proteins in the short term (days), and incorporation of 15N-proline into the tissue to calculate the acute FSR (hours). RESULTS Both the rupture and the control samples showed consistently lower levels of 14C compared with the predicted level of 14C in a healthy tendon, which indicated increased tendon turnover in a fraction (48% newly synthesized) of the Achilles tendon already for a prolonged period before the rupture. Over the first days after the rupture, the synthesis rate for collagen was relatively constant, and the average synthesis rate on the day of surgery (2-14 days after the rupture) was 0.025% per hour, irrespective of the length of time after a rupture and the site of sampling (rupture vs control). No differences were found in the FSR between the rupture and control samples in the days after the rupture. CONCLUSION Higher than normal tissue turnover in the Achilles tendon before a rupture indicated that changes in the tendon tissue preceded the injury. In addition, we observed no increase in tendon collagen tissue turnover in the first 2 weeks after an ATR. This favors the view that an increase in the formation of new tendon collagen is not an immediate phenomenon during the regeneration of ruptured tendons in patients. REGISTRATION NCT03931486 (ClinicalTrials.gov identifier).
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Affiliation(s)
- Allan Cramer
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Olsen
- Aarhus AMS Centre, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - Per Hölmich
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristoffer Weisskirchner Barfod
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
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Calejo I, Reis RL, Domingues RMA, Gomes ME. Texturing Hierarchical Tissues by Gradient Assembling of Microengineered Platelet-Lysates Activated Fibers. Adv Healthc Mater 2022; 11:e2102076. [PMID: 34927396 DOI: 10.1002/adhm.202102076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/14/2021] [Indexed: 11/07/2022]
Abstract
The heterogeneity of hierarchical tissues requires designing multipart engineered constructs as suitable tissue replacements. Herein, the incorporation of platelet lysate (PL) within an electrospun fiber core is proposed aiming for the fabrication of functionally graded 3D scaffolds for heterotypic tissues regeneration, such as tendon-to-bone interfaces. First, anisotropic yarns (A-Yarns) and isotropic threads with nanohydroxyapatite (I-Threads/PL@nHAp) are fabricated to recreate the tendon- and bone-microstructures and both incorporated with PL using emulsion electrospinning for a sustained and local delivery of growth factors, cytokines, and chemokines. Biological performance using human adipose-derived stem cells demonstrates that A-Yarns/PL induce a higher expression of scleraxis, a tenogenic-marker, while in I-Threads/PL@nHAp, higher alkaline phosphatase activity and matrix mineralization suggest an osteogenic commitment without the need for biochemical supplementation compared to controls. As a proof-of-concept, functional 3D gradient scaffolds are fabricated using a weaving technique, resulting in 3D textured hierarchical constructs with gradients in composition and topography. Additionally, the precise delivery of bioactive cues together with in situ biophysical features guide the commitment into a phenotypic gradient exhibiting chondrogenic and osteochondrogenic profiles in the interface of scaffolds. Overall, a promising patch solution for the regeneration of tendon-to-bone tissue interface through the fabrication of PL-functional 3D gradient constructs is demonstrated.
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Affiliation(s)
- Isabel Calejo
- 3B's Research Group i3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics University of Minho Barco Guimarães 4805‐017 Portugal
| | - Rui L. Reis
- 3B's Research Group i3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics University of Minho Barco Guimarães 4805‐017 Portugal
| | - Rui M. A. Domingues
- 3B's Research Group i3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics University of Minho Barco Guimarães 4805‐017 Portugal
| | - Manuela E. Gomes
- 3B's Research Group i3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics University of Minho Barco Guimarães 4805‐017 Portugal
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Insertional versus non-insertional tendoachilles tears: a comparative analysis of various predisposing factors and outcome following a repair. INTERNATIONAL ORTHOPAEDICS 2022; 46:1009-1017. [PMID: 35165787 DOI: 10.1007/s00264-022-05337-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/31/2022] [Indexed: 10/19/2022]
Abstract
BACKGROUND Association of tendon degeneration, pre-existing posterior heel pain, Haglund's bump, retrocalcaneal spur, and mode of injury varies for the insertional and non-insertional type of tendoachilles tears (TA). PURPOSE The study compares the various predisposing factors that determine the distinct type of TA tear and the outcome following a repair. METHODS This is a retrospective study of the patients who underwent tendoachilles repair during January 2012-June 2018. Patients above 18 years with a minimum follow-up of two years were included. Patients with calcaneal tuberosity avulsions, prior surgeries, and open injuries were excluded. Patients were divided into groups 1 (insertional tears (IT)) and 2 (non-insertional tears (NIT)), and further subdivided based on the tendon degeneration (as D-degenerative and N-normal sub types) from ultrasound findings. AOFAS score and predisposing factors like degeneration, posterior heel pain, Haglund's bump, spur, and mechanism of injury were compared between the groups. RESULTS The study included N = 146 with a mean age of 51.6 years and mean follow-up of 38.6 (range 24 to 96) months. IT associated with degeneration (IT-D) had a trivial fall as the predominant mechanism (P < 0.001). All patients had significant postoperative improvement of scores with no significant difference between the groups (P = 0.59) and subgroups (P = 0.27).75.34% had degenerative tendon, of which 64.5% were in the IT group and the rest in the NIT group (P = 0.02). 51.4% patients had a Haglund bump in the IT group and n.s. (P = 0.9). Forty-seven percent of patients had pre-existing posterior heel pain, 68% in IT and 32% in NIT (P = 0.04). Subgroup analysis revealed 65% of patients were in the IT-D subgroup (P < 0.001). CONCLUSION Predisposing factors like posterior heel pain, tendon degeneration, and trivial trauma have a strong propensity for insertional TA tear. In contrast, the prominence of Haglund's bump does not predispose to a distinct type of TA tears. The outcome following a surgical repair-yields good results with no difference between the two groups.
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Patel D, Zamboulis DE, Spiesz EM, Birch HL, Clegg PD, Thorpe CT, Screen HR. Structure-function specialisation of the interfascicular matrix in the human achilles tendon. Acta Biomater 2021; 131:381-390. [PMID: 34271169 PMCID: PMC8388240 DOI: 10.1016/j.actbio.2021.07.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/14/2021] [Accepted: 07/08/2021] [Indexed: 01/24/2023]
Abstract
Tendon consists of highly aligned collagen-rich fascicles surrounded by interfascicular matrix (IFM). Some tendons act as energy stores to improve locomotion efficiency, but such tendons commonly obtain debilitating injuries. In equine tendons, energy storing is achieved primarily through specialisation of the IFM. However, no studies have investigated IFM structure-function specialisation in human tendons. Here, we compare the human positional anterior tibial tendon and energy storing Achilles tendons, testing the hypothesis that the Achilles tendon IFM has specialised composition and mechanical properties, which are lost with ageing. Data demonstrate IFM specialisation in the energy storing Achilles, with greater elasticity and fatigue resistance than in the positional anterior tibial tendon. With ageing, alterations occur predominantly to the proteome of the Achilles IFM, which are likely responsible for the observed trends towards decreased fatigue resistance. Knowledge of these key energy storing specialisations and their changes with ageing offers crucial insight towards developing treatments for tendinopathy. Statement of significance Developing effective therapeutics or preventative measures for tendon injury necessitates the understanding of healthy tendon function and mechanics. By establishing structure-function relationships in human tendon and determining how these are affected by ageing, potential targets for therapeutics can be identified. In this study, we have used a combination of mechanical testing, immunolabelling and proteomics analysis to study structure-function specialisations in human tendon. We demonstrate that the interfascicular matrix is specialised for energy storing in the Achilles tendon, and that its proteome is altered with ageing, which is likely responsible for the observed trends towards decreased fatigue resistance. Knowledge of these key energy storing specialisations and their changes with ageing offers crucial insight towards developing treatments and preventative approaches for tendinopathy.
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Derman İD, Şenel EC, Ferhanoğlu O, Çilesiz İ, Kazanci M. Effect of Heat Level and Expose Time on Denaturation of Collagen Tissues. Cell Mol Bioeng 2020; 14:113-119. [PMID: 33643470 DOI: 10.1007/s12195-020-00653-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/16/2020] [Indexed: 10/23/2022] Open
Abstract
Introduction The applied heat level and expose time are main issues in certain operations/applications, such as a laser assisted tissue welding, preparation of collagen-based biomaterials (films, implants). Therefore, the precise investigation of these parameters is crucial. The results can serve as a guideline to assess potential effects while maintaining the functionality of the collagen structures. Methods Collagen tissues from rat-tail tendon, calfskin, and bones are soaked in buffer solutions, then examined by microscope at different temperature levels. Results Increase in temperature reduced the microscopically observed collagen crimp contrast for calfskin and rat-tail tendons but not for bone tissues. The contrast level for rat tail tendon decreased down to 80% of its initial value at 37, 157, and 266 s for 70, 65, and 60 °C, respectively. The decrease in the crimp contrast was about only 25% and 2% at 55 and 50 °C after 2 h, respectively. 50% drop in contrast level was occurred for the skin samples at 16, 90, 110 and 1900 s for 70, 65, and 60 °C, respectively. The bone samples, did not show any significant differences in contrast levels. Conclusion The observed denaturation behaviours are in line with Arrhenius Law. This study could be expanded on to other types of tissues at wider temperature ranges to make a guideline for biological/medical processes that radiate heat in order to assess their side effects on collagen and other proteins.
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Affiliation(s)
- İrem Deniz Derman
- Electronics and Communication Engineering, Istanbul Technical University, 34469 Istanbul, Turkey.,Biomedical Engineering Graduate Program, Istanbul Technical University, 34469 Istanbul, Turkey
| | - Esat Can Şenel
- Electronics and Communication Engineering, Istanbul Technical University, 34469 Istanbul, Turkey.,Biomedical Engineering Graduate Program, Istanbul Technical University, 34469 Istanbul, Turkey
| | - Onur Ferhanoğlu
- Electronics and Communication Engineering, Istanbul Technical University, 34469 Istanbul, Turkey
| | - İnci Çilesiz
- Electronics and Communication Engineering, Istanbul Technical University, 34469 Istanbul, Turkey
| | - Murat Kazanci
- Biomedical Engineering Department, School of Engineering and Natural Sciences, Istanbul Medeniyet University, 34700 Istanbul, Turkey
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Baldwin M, Snelling S, Dakin S, Carr A. Augmenting endogenous repair of soft tissues with nanofibre scaffolds. J R Soc Interface 2019; 15:rsif.2018.0019. [PMID: 29695606 DOI: 10.1098/rsif.2018.0019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 04/04/2018] [Indexed: 12/21/2022] Open
Abstract
As our ability to engineer nanoscale materials has developed we can now influence endogenous cellular processes with increasing precision. Consequently, the use of biomaterials to induce and guide the repair and regeneration of tissues is a rapidly developing area. This review focuses on soft tissue engineering, it will discuss the types of biomaterial scaffolds available before exploring physical, chemical and biological modifications to synthetic scaffolds. We will consider how these properties, in combination, can provide a precise design process, with the potential to meet the requirements of the injured and diseased soft tissue niche. Finally, we frame our discussions within clinical trial design and the regulatory framework, the consideration of which is fundamental to the successful translation of new biomaterials.
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Affiliation(s)
- Mathew Baldwin
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Sarah Snelling
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Stephanie Dakin
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Andrew Carr
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
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Abstract
The pathologic conditions of the Achilles tendon are best understood in the context of its unique anatomy and functional demands. Some of these unique considerations include its high physiologic load demands, microscopic tissue composition, muscular origin spanning the knee joint, intimate insertional relationship with the plantar fascia, sensory innervation, and vascular supply with watershed areas. Risks of both acute rupture and chronic tendinopathy are affected by the tendon's anatomy and its functional demands. The tendon's functional anatomy changes with advancing age, notably in its collagen composition and vascular supply.
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Hamdia KM, Marino M, Zhuang X, Wriggers P, Rabczuk T. Sensitivity analysis for the mechanics of tendons and ligaments: Investigation on the effects of collagen structural properties via a multiscale modeling approach. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2019; 35:e3209. [PMID: 30989796 DOI: 10.1002/cnm.3209] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
The effects of the stochasticity of collagen-related structural properties on the biomechanical properties of tendons and ligaments are investigated in this study. The tissue mechanics is modeled by means of a macroscale constitutive model based on a multiscale structural approach. This rationale allows to introduce model parameters directly associated with tissue structural and biochemical features, opening to physically motivated parametric studies. Variance and density-based global sensitivity analyses are employed, together with the quantification of output uncertainty due to stochastic variations of parameters. Novel insights on tissue structure-mechanics relationship are provided, quantifying the dependence between mechanical output quantities on specific collagen-related structural features. Moreover, the uncertainty quantification shows that model predictions provided by the multiscale structural approach are reliable with respect to inevitable uncertainties in tissue structure. Addressing rat tail tendons, the use of average values in tissue properties returns a constitutive response that fits well-available experimental data, and it is robust with respect to parameter stochasticity.
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Affiliation(s)
- Khader M Hamdia
- Division of Computational Mechanics, Ton Duc Thang University, Ho Chi Minh City, Vietnam
- Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam
| | - Michele Marino
- Institute of Continuum Mechanics, Leibniz Universit.t Hannover, Hannover, Germany
| | - Xiaoying Zhuang
- Division of Computational Mechanics, Ton Duc Thang University, Ho Chi Minh City, Vietnam
- Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam
| | - Peter Wriggers
- Institute of Continuum Mechanics, Leibniz Universit.t Hannover, Hannover, Germany
| | - Timon Rabczuk
- Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai, China
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Tendon and Ligament Injuries in Elite Rugby: The Potential Genetic Influence. Sports (Basel) 2019; 7:sports7060138. [PMID: 31167482 PMCID: PMC6628064 DOI: 10.3390/sports7060138] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 01/13/2023] Open
Abstract
This article reviews tendon and ligament injury incidence and severity within elite rugby union and rugby league. Furthermore, it discusses the biological makeup of tendons and ligaments and how genetic variation may influence this and predisposition to injury. Elite rugby has one of the highest reported injury incidences of any professional sport. This is likely due to a combination of well-established injury surveillance systems and the characteristics of the game, whereby high-impact body contact frequently occurs, in addition to the high intensity, multispeed and multidirectional nature of play. Some of the most severe of all these injuries are tendon and ligament/joint (non-bone), and therefore, potentially the most debilitating to a player and playing squad across a season or World Cup competition. The aetiology of these injuries is highly multi-factorial, with a growing body of evidence suggesting that some of the inter-individual variability in injury susceptibility may be due to genetic variation. However, little effort has been devoted to the study of genetic injury traits within rugby athletes. Due to a growing understanding of the molecular characteristics underpinning the aetiology of injury, investigating genetic variation within elite rugby is a viable and worthy proposition. Therefore, we propose several single nucleotide polymorphisms within candidate genes of interest; COL1A1, COL3A1, COL5A1, MIR608, MMP3, TIMP2, VEGFA, NID1 and COLGALT1 warrant further study within elite rugby and other invasion sports.
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Bojsen-Møller J, Magnusson SP. Mechanical properties, physiological behavior, and function of aponeurosis and tendon. J Appl Physiol (1985) 2019; 126:1800-1807. [DOI: 10.1152/japplphysiol.00671.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During human movement, the muscle and tendinous structures interact as a mechanical system in which forces are generated and transmitted to the bone and energy is stored and released to optimize function and economy of movement and/or to reduce risk of injury. The present review addresses certain aspects of how the anatomical design and mechanical and material properties of the force-transmitting tissues contribute to the function of the muscle-tendon unit and thus overall human function. The force-bearing tissues are examined from a structural macroscopic point of view down to the nanoscale level of the collagen fibril. In recent years, the understanding of in vivo mechanical function of the force-bearing tissues has increased, and it has become clear that these tissues adapt to loading and unloading and furthermore that force transmission mechanics is more complex than previously thought. Future investigations of the force-transmitting tissues in three dimensions will enable a greater understanding of the complex functional interplay between muscle and tendon, with relevance for performance, injury mechanisms, and rehabilitation strategies.
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Affiliation(s)
- Jens Bojsen-Møller
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
- Section for Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - S. Peter Magnusson
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Occupational and Physical Therapy, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
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Cury DP, Schäfer BT, de Almeida SRY, Righetti MMDS, Watanabe IS. Application of a Purified Protein From Natural Latex and the Influence of Suture Type on Achilles Tendon Repair in Rats. Am J Sports Med 2019; 47:901-914. [PMID: 30759353 DOI: 10.1177/0363546518822836] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The prolonged tendon-healing process, the high costs associated with treatment, the increase in the number of injuries over the past decades, and the lack of consensus on the optimal treatment of tendon injuries are a global problem. Restoring the normal tendon anatomy and decreasing the healing time are key factors for treatment advancement. HYPOTHESIS Application of a purified protein from natural latex (PPNL) accelerates the healing process, increasing collagen synthesis and decreasing metalloproteinases. PPNL associated with a simpler suture technique should decrease the healing time. STUDY DESIGN Controlled laboratory study. METHODS Injury, surgery, and treatment with PPNL were conducted with male Sprague-Dawley rats. Two suture techniques were used: U-suture, a simpler and lesser traumatic technique, and Kessler-Tajima, to avoid strangulation of the microcirculation. Achilles tendons were completely sectioned, and 100 µL of 0.1% PPNL was applied on the tendon during surgery. Tendon morphology, distribution, and quantity of collagen types I and III, as well as expression of TIMP-1, TIMP-2, MMP-2, and MMP-9 and ultrastructural aspects of cells and collagen fibrils, were assessed after 2 and 4 weeks. RESULTS PPNL treatment improved collagen type I synthesis and reduced MMP-2 expression. All groups showed a 6.8-times increase in tendon weight as compared with the control group after 2 weeks and a 5.2-times increase after 4 weeks. All groups showed an increase in diameter after 4 weeks, except for the ones treated with PPNL, which showed a slight reduction in diameter. The peak of concentration of collagen fibrils with a 80-nm diameter was 27.79% in the control group; all other experimental groups presented fibrils between 50 and 60 nm. However, the best results were observed with Kessler-Tajima suture associated with PPNL. CONCLUSION/CLINICAL RELEVANCE There are no known medicines or substances capable of aiding the tendon healing process besides surgery. The discovery of a substance able to improve this process and decrease its duration represents an important advancement in orthopaedic medicine.
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Affiliation(s)
- Diego Pulzatto Cury
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Bárbara Tavares Schäfer
- Department of Surgery, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | | | | | - Ii-Sei Watanabe
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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13
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More tendon degeneration in patients with shoulder osteoarthritis. Knee Surg Sports Traumatol Arthrosc 2019; 27:267-275. [PMID: 30284007 DOI: 10.1007/s00167-018-5186-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 09/27/2018] [Indexed: 12/27/2022]
Abstract
PURPOSE Tendon disorders are a major problem in the general population. It is known that rotator cuff tendinopathy contributes to osteoarthritis (OA) of the shoulder. The aim of the study was to analyse the presence of tendinopathy in patients with shoulder OA and an intact rotator cuff, using a multimodal approach. METHODS Thirteen consecutive patients median age 67 (52-84) years, with OA of the shoulder, and 13 consecutive control patients, with a fracture of the proximal humerus, median age 70 (51-84) years, underwent an open biopsy procedure from the biceps and subscapularis tendon in conjunction with shoulder arthroplasty. In addition to a macroscopic evaluation, the samples underwent histologic, morphologic and ultrastructural analyses in light and transmission electron microscopy. RESULTS Macroscopic degeneration was found in 15 of 26 specimen in the OA group but in seven of 25 in the control group (p = 0.048). The histologic analysis revealed a non-significant difference for the total degeneration score (TDS) between the study groups. The morphologic evaluation of the samples revealed that the OA group had significantly more samples with non-homogeneous extracellular matrix (ECM), (p = 0.048). Ultrastructurally, the OA group revealed a significantly larger fibril diameter in the biceps tendon (p < 0.0001) but not in the subscapularis tendon compared with the control group. CONCLUSION A significantly worse macroscopic appearance and significantly more morphologically inhomogeneous ECM, indicating more tendon degeneration, were found in the OA group compared with the control group. This indicates that it could be beneficial to treat the tendinosis in an early stage to decrease symptoms from the OA. STUDY DESIGN Level of evidence, III.
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14
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Magnusson SP, Kjaer M. The impact of loading, unloading, ageing and injury on the human tendon. J Physiol 2018; 597:1283-1298. [PMID: 29920664 DOI: 10.1113/jp275450] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/30/2018] [Indexed: 12/28/2022] Open
Abstract
A tendon transfers force from the contracting muscle to the skeletal system to produce movement and is therefore a crucial component of the entire muscle-tendon complex and its function. However, tendon research has for some time focused on mechanical properties without any major appreciation of potential cellular and molecular changes. At the same time, methodological developments have permitted determination of the mechanical properties of human tendons in vivo, which was previously not possible. Here we review the current understanding of how tendons respond to loading, unloading, ageing and injury from cellular, molecular and mechanical points of view. A mechanistic understanding of tendon tissue adaptation will be vital for development of adequate guidelines in physical training and rehabilitation, as well as for optimal injury treatment.
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Affiliation(s)
- S Peter Magnusson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, NV.,Department of Physical and Occupational Therapy Bispebjerg Hospital, Copenhagen, NV.,Center for Healthy Aging, Department of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, NV.,Center for Healthy Aging, Department of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
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15
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Farfaras S, Ejerhed LE, Hallström EK, Hultenby K, Meknas K, Movin T, Papadogiannakis N, Kartus JT. More histologic and ultrastructural degenerative signs in the subscapularis tendon and the joint capsule in male patients with shoulder impingement. Knee Surg Sports Traumatol Arthrosc 2018; 26:79-87. [PMID: 28255657 PMCID: PMC5754398 DOI: 10.1007/s00167-017-4442-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 01/20/2017] [Indexed: 11/24/2022]
Abstract
PURPOSE The purpose of the present study was to analyze biopsy samples from the subscapularis tendon and from the joint capsule from male patients with shoulder impingement syndrome (SAIS) and compare them with samples from male patients with post-traumatic recurrent shoulder instability. The hypothesis of the study was that patients with SAIS would have more histologic and ultrastructural degenerative changes in their subscapularis tendon and joint capsule than patients with post-traumatic recurrent shoulder instability. METHODS Male patients scheduled for surgery, with either subacromial decompression or Bankart reconstruction, were included. Four biopsies from each patient were obtained from the capsule and four from the subscapularis tendon during arthroscopic surgery. The histologic characteristics and the presence of glycosaminoglycans were assessed using the light microscope, and the ultrastructure was assessed using a transmission electron microscope. RESULTS Eight patients, median age 53 (45-74) years (p < 0.0001), were included in the impingement group, and 12 patients, median age 27 (22-48) years, were included in the instability group. The histologic assessment revealed significantly higher cellularity and total degeneration score in the capsule (p = 0.016 and p = 0.014 respectively) in patients with subacromial impingement compared with the instability patients. The corresponding finding was not made for the subscapularis tendon. The ultrastructural evaluation revealed that the instability patients had more fibrils with a large diameter (indicating less degeneration) in both the subscapularis tendon and the capsule compared with the impingement patients (p < 0.0001). CONCLUSION Male patients with subacromial impingement have more histologic and ultrastructural degenerative changes in their shoulder compared with patients with post-traumatic recurrent shoulder instability. CLINICAL RELEVANCE It appears that in patients with subacromial impingement, the whole shoulder joint is affected and not only the subacromial space. It is the opinion of the authors that intra-articular therapeutic injections could be tried more often in these patients. LEVEL OF EVIDENCE III.
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Affiliation(s)
- Stefanos Farfaras
- Department of Orthopedics, NU-Hospital Group Trollhättan/Uddevalla, Uddevalla Sjukhus, 451, Uddevalla, Sweden. .,Gothenburg University-Sahlgrenska Academy, Gothenburg, Sweden.
| | - Lars Erik Ejerhed
- Department of Orthopedics, NU-Hospital Group Trollhättan/Uddevalla, Uddevalla Sjukhus, 451 Uddevalla, Sweden
| | - Erling K. Hallström
- Department of Orthopedics, NU-Hospital Group Trollhättan/Uddevalla, Uddevalla Sjukhus, 451 Uddevalla, Sweden ,Gothenburg University-Sahlgrenska Academy, Gothenburg, Sweden
| | - Kjell Hultenby
- Division of Clinical Research Center, Department of Laboratory Medicine, Karolinska Institute Stockholm, Stockholm, Sweden
| | - Khaled Meknas
- Bone and Joint Research Group, Department of Orthopedics, Institute of Clinical Medicine, University Hospital North Norway, The Arctic University of Norway, Tromsø, Norway
| | - Tomas Movin
- Department of Clinical Science, Karolinska Institute, Stockholm, Sweden
| | - Nikos Papadogiannakis
- Division of Pathology, Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden
| | - Jüri-Toomas Kartus
- Department of Orthopedics, NU-Hospital Group Trollhättan/Uddevalla, Uddevalla Sjukhus, 451 Uddevalla, Sweden ,Gothenburg University-Sahlgrenska Academy, Gothenburg, Sweden
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16
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Laranjeira M, Domingues RMA, Costa-Almeida R, Reis RL, Gomes ME. 3D Mimicry of Native-Tissue-Fiber Architecture Guides Tendon-Derived Cells and Adipose Stem Cells into Artificial Tendon Constructs. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1700689. [PMID: 28631375 DOI: 10.1002/smll.201700689] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 04/12/2017] [Indexed: 05/18/2023]
Abstract
Tendon and ligament (T/L) function is intrinsically related with their unique hierarchically and anisotropically organized extracellular matrix. Their natural healing capacity is, however, limited. Here, continuous and aligned electrospun nanofiber threads (CANT) based on synthetic/natural polymer blends mechanically reinforced with cellulose nanocrystals are produced to replicate the nanoscale collagen fibrils grouped into microscale collagen fibers that compose the native T/L. CANT are then incrementally assembled into 3D hierarchical scaffolds, resulting in woven constructions, which simultaneously mimic T/L nano-to-macro architecture, nanotopography, and nonlinear biomechanical behavior. Biological performance is assessed using human-tendon-derived cells (hTDCs) and human adipose stem cells (hASCs). Scaffolds nanotopography and microstructure induce a high cytoskeleton elongation and anisotropic organization typical of tendon tissues. Moreover, the expression of tendon-related markers (Collagen types I and III, Tenascin-C, and Scleraxis) by both cell types, and the similarities observed on their expression patterns over time suggest that the developed scaffolds not only prevent the phenotypic drift of hTDCs, but also trigger tenogenic differentiation of hASCs. Overall, these results demonstrate a feasible approach for the scalable production of 3D hierarchical scaffolds that exhibit key structural and biomechanical properties, which can be advantageously explored in acellular and cellular T/L TE strategies.
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Affiliation(s)
- Mariana Laranjeira
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017, Barco, Guimarães, Portugal
- ICVS/3B's-PT Associate Laboratory, Braga, Portugal
| | - Rui M A Domingues
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017, Barco, Guimarães, Portugal
- ICVS/3B's-PT Associate Laboratory, Braga, Portugal
| | - Raquel Costa-Almeida
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017, Barco, Guimarães, Portugal
- ICVS/3B's-PT Associate Laboratory, Braga, Portugal
| | - Rui L Reis
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017, Barco, Guimarães, Portugal
- ICVS/3B's-PT Associate Laboratory, Braga, Portugal
| | - Manuela E Gomes
- 3B's Research Group - Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Avepark - Parque de Ciência e Tecnologia, Zona Industrial da Gandra, 4805-017, Barco, Guimarães, Portugal
- ICVS/3B's-PT Associate Laboratory, Braga, Portugal
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17
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Qianman B, Jialihasi A, Asilehan B, Kubai A, Aibek R, Wupuer A, Tangkejie W, Maimaitiaili A, Shawutali N, Badelhan A, Aizezi A, Aisaiding A, Wuerliebieke J, Bakyt Y, Makemutibieke E, Jielile J. Active exercise promotes Achilles tendon healing and is accompanied by the upregulation of collapsin response mediator protein‑2 in rats. Mol Med Rep 2017; 16:2355-2360. [PMID: 28677754 DOI: 10.3892/mmr.2017.6889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 01/20/2017] [Indexed: 11/05/2022] Open
Abstract
Collapsin response mediator protein-2 (CRMP-2) is involved in neurite elongation and regeneration; however, its role in wound healing remains to be elucidated. The present study aimed to investigate the effects of active mobilization treatment on Achilles tendon healing and to determine the role of CRMP‑2 in the healing process. Sprague Dawley rats were subjected to Achilles tendon injury, which was verified by hematoxylin and eosin staining and scanning electronic microscopy. Immobilization induced the disruption of collagen fibril arrangement and promoted collagen fibril damage. The average collagen fibril perimeter in the active mobilization group was significantly increased compared with in the immobilization group (125.6±0.8 nm vs. 119.9±1.7 nm; P<0.05). In addition, immunohistological analysis revealed that CRMP‑2 expression was significantly upregulated, particularly in the ruptured site of Achilles tendon tissues derived from animals in the mobilization group compared with the immobilization group (0.32±0.00 vs. 0.08±0.00; P<0.05). The increased CRMP‑2 levels were also confirmed by western blotting (active mobilization group, 0.71±0.03; immobilization group, 0.49±0.01 nm; P<0.05). These results indicated that active mobilization may promote Achilles tendon healing via upregulation of CRMP‑2 protein expression.
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Affiliation(s)
- Bayixiati Qianman
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Ayidaer Jialihasi
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Batiza Asilehan
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Aliya Kubai
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Rakimbaiev Aibek
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Aikeremu Wupuer
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Wulanbai Tangkejie
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Abudouheilil Maimaitiaili
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Nuerai Shawutali
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Aynaz Badelhan
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Adili Aizezi
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Amuding Aisaiding
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Jianati Wuerliebieke
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Yerzat Bakyt
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Elihaer Makemutibieke
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
| | - Jiasharete Jielile
- Department of Orthopedics Centre, The First Teaching Hospital of Xinjiang Medical University, Kazakh Medical Association of Xinjiang Uygur Autonomous Region and The Sports Medicine Research Centre of Orthopedics Research Institute, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China
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18
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Pang X, Wu JP, Allison GT, Xu J, Rubenson J, Zheng MH, Lloyd DG, Gardiner B, Wang A, Kirk TB. Three dimensional microstructural network of elastin, collagen, and cells in Achilles tendons. J Orthop Res 2017; 35:1203-1214. [PMID: 27002477 DOI: 10.1002/jor.23240] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 03/17/2016] [Indexed: 02/04/2023]
Abstract
Similar to most biological tissues, the biomechanical, and functional characteristics of the Achilles tendon are closely related to its composition and microstructure. It is commonly reported that type I collagen is the predominant component of tendons and is mainly responsible for the tissue's function. Although elastin has been found in varying proportions in other connective tissues, previous studies report that tendons contain very small quantities of elastin. However, the morphology and the microstructural relationship among the elastic fibres, collagen, and cells in tendon tissue have not been well examined. We hypothesize the elastic fibres, as another fibrillar component in the extracellular matrix, have a unique role in mechanical function and microstructural arrangement in Achilles tendons. It has been shown that elastic fibres present a close connection with the tenocytes. The close relationship of the three components has been revealed as a distinct, integrated and complex microstructural network. Notably, a "spiral" structure within fibril bundles in Achilles tendons was observed in some samples in specialized regions. This study substantiates the hierarchical system of the spatial microstructure of tendon, including the mapping of collagen, elastin and tenocytes, with 3-dimensional confocal images. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1203-1214, 2017.
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Affiliation(s)
- Xin Pang
- Department of Mechanical Engineering, 3D Imaging and Bioengineering Laboratory, Curtin University, Bentley, Western Australia 6102, Australia
| | - Jian-Ping Wu
- Department of Mechanical Engineering, 3D Imaging and Bioengineering Laboratory, Curtin University, Bentley, Western Australia 6102, Australia
| | - Garry T Allison
- The School of Physiotherapy and Exercise Sciences, Curtin University, Western Australia, Australia
| | - Jiake Xu
- The School of Pathology and Laboratory Medicine, University of Western Australia, Western Australia, Australia
| | - Jonas Rubenson
- Department of Kinesiology, Pennsylvania State University, Pennsylvania.,School of Sport Science, Exercise and Health, University of Western Australia, Western Australia, Australia
| | - Ming-Hao Zheng
- Centre for Orthopaedic Research, School of Surgery, University of Western Australia, Western Australia, Australia
| | - David G Lloyd
- Centre for Musculoskeletal Research, Menzies Health Institute Queensland, Griffith University, Queensland, Australia
| | - Bruce Gardiner
- School of Engineering and Information Technology, Murdoch University, Western Australia, Australia
| | - Allan Wang
- Centre for Orthopaedic Research, School of Surgery, University of Western Australia, Western Australia, Australia.,St John of God Hospital, Western Australia, Australia
| | - Thomas Brett Kirk
- Department of Mechanical Engineering, 3D Imaging and Bioengineering Laboratory, Curtin University, Bentley, Western Australia 6102, Australia
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19
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Vergari C, Chan D, Clarke A, Mansfield JC, Meakin JR, Winlove PC. Bovine and degenerated human annulus fibrosus: a microstructural and micromechanical comparison. Biomech Model Mechanobiol 2017; 16:1475-1484. [PMID: 28378119 PMCID: PMC5511600 DOI: 10.1007/s10237-017-0900-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/15/2017] [Indexed: 01/03/2023]
Abstract
The complex structure of the annulus fibrosus is strongly related to its mechanical properties. Recent work showed that it is possible to observe the relative movement of fibre bundles in loaded cow tail annulus; the aim of this work was to describe and quantify annulus fibrosus micromechanics in degenerated human disc, and compare it with cow tail annulus, an animal model often used in the literature. Second harmonic generation was used to image the collagen matrix in twenty strips of annulus fibrosus harvested from intervertebral disc of seven patients undergoing surgery. Samples were loaded to 6% tensile strain in 1% steps. Elastic modulus was calculated from loading curves, and micromechanical strains were calculated from the images using custom software. The same protocol was applied to twenty strips of annulus harvested from cow tail discs. Significant morphological differences were found between human and cow tail samples, the most striking being the lack of collagen fibre crimp in the former. Fibres were also observed bending and running from one lamella to the other, forming a strong flexible interface. Interdigitation of fibre bundles was also present at this interface. Quantitative results show complex patterns of inter-bundle and inter-lamellar behaviour, with inter-bundle sliding being the main strain mechanism. Elastic modulus was similar between species, and it was not affected by the degree of degeneration. This work gives an insight into the complex structure and mechanical function of the annulus fibrosus, which should be accounted for in disc numerical modelling.
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Affiliation(s)
- Claudio Vergari
- School of Physics and Astronomy, University of Exeter, Physics Building, Stocker Road, Exeter, EX4 4QL, UK.
| | - Daniel Chan
- Peninsula Spine Unit, Princess Elizabeth Orthopaedic Centre, Royal Devon and Exeter Hospital, Barrack Road, Exeter, Devon, EX2 5DW, UK
| | - Andrew Clarke
- Peninsula Spine Unit, Princess Elizabeth Orthopaedic Centre, Royal Devon and Exeter Hospital, Barrack Road, Exeter, Devon, EX2 5DW, UK
| | - Jessica C Mansfield
- School of Physics and Astronomy, University of Exeter, Physics Building, Stocker Road, Exeter, EX4 4QL, UK
| | - Judith R Meakin
- School of Physics and Astronomy, University of Exeter, Physics Building, Stocker Road, Exeter, EX4 4QL, UK
| | - Peter C Winlove
- School of Physics and Astronomy, University of Exeter, Physics Building, Stocker Road, Exeter, EX4 4QL, UK
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20
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Kauwe M. Acute Achilles Tendon Rupture: Clinical Evaluation, Conservative Management, and Early Active Rehabilitation. Clin Podiatr Med Surg 2017; 34:229-243. [PMID: 28257676 DOI: 10.1016/j.cpm.2016.10.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The Achilles tendon (AT) is the strongest, largest, and most commonly ruptured tendon in the human body. Physical examination provides high sensitivity and specificity. Imaging studies are not recommended unless there are equivocal findings in the physical examination. Recent studies have shown that the risk of re-rupture is negated with implementation of functional rehabilitation protocols. Heterogeneity in study design makes conclusions on the specifics of functional rehabilitation protocols difficult; however, it is clear that early weight bearing and early controlled mobilization lead to better patient outcome and satisfaction in both surgically and conservatively treated populations.
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Affiliation(s)
- Merrell Kauwe
- Foot and Ankle Department, UnityPoint Trinity Regional Medical Center, 804 Kenyon Road, Suite 310, Fort Dodge, IA 50501, USA.
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21
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Lavagnino M, Brooks AE, Oslapas AN, Gardner KL, Arnoczky SP. Crimp length decreases in lax tendons due to cytoskeletal tension, but is restored with tensional homeostasis. J Orthop Res 2017; 35:573-579. [PMID: 27878991 DOI: 10.1002/jor.23489] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/10/2016] [Indexed: 02/04/2023]
Abstract
Collagen crimp morphology is thought to contribute to the material behavior of tendons and may reflect the local mechanobiological environment of tendon cells. Following loss of collagen tension in tendons, tenocytes initiate a contraction response that shortens tendon length which, in turn, may alter crimp patterns. We hypothesized that changes in the crimp pattern of tendons are the result of cell-based contractions which are governed by relative tautness/laxity of the collagen matrix. To determine the relationship between crimp pattern and tensional homeostasis, rat tail tendon fascicles (RTTfs) were either allowed to freely contract or placed in clamps with 10% laxity for 7 days. The freely contracting RTTfs showed a significant decrease in percent crimp length on both day 5 (3.66%) and day 7 (7.70%). This decrease in crimp length significantly correlated with the decrease in freely contracting RTTf length. Clamped RTTfs demonstrated a significant decrease in percent crimp length on day 5 (1.7%), but no significant difference in percent crimp length on day 7 (0.57%). The results demonstrate that the tendon crimp pattern appears to be under cellular control and is a reflection of the local mechanobiological environment of the extracellular matrix. The ability of tenocytes to actively alter the crimp pattern of collagen fibers also suggests that tenocytes can influence the viscoelastic properties of tendon. Understanding the interactions between tenocytes and their extracellular matrix may lead to further insight into the role tendon cells play in maintaining tendon heath and homeostasis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:573-579, 2017.
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Affiliation(s)
- Michael Lavagnino
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, Michigan, 48824
| | - Andrew E Brooks
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, Michigan, 48824
| | - Anna N Oslapas
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, Michigan, 48824
| | - Keri L Gardner
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, Michigan, 48824
| | - Steven P Arnoczky
- Laboratory for Comparative Orthopaedic Research, College of Veterinary Medicine, Michigan State University, 784 Wilson Road, East Lansing, Michigan, 48824
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22
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Nuri L, Obst SJ, Newsham-West R, Barrett RS. The tendinopathic Achilles tendon does not remain iso-volumetric upon repeated loading: insights from 3D ultrasound. J Exp Biol 2017; 220:3053-3061. [DOI: 10.1242/jeb.159764] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/12/2017] [Indexed: 12/22/2022]
Abstract
Mid-portion Achilles tendinopathy (MAT) alters the normal three-dimensional (3D) morphology of the Achilles tendon (AT) at rest and under a single tensile load. However, how MAT changes the 3D morphology of AT during repeated loading remains unclear. This study compared the AT longitudinal, transverse and volume strains during repeated loading in MAT with those of the contralateral tendon in people with unilateral MAT. Ten adults with unilateral MAT performed 10 successive 25 second submaximal (50%) voluntary isometric plantarflexion contractions with both legs. Freehand 3D ultrasound scans were recorded and used to measure whole AT, free AT, and proximal AT longitudinal strains and free AT cross-sectional area (CSA) and volume strains. The free AT experienced higher longitudinal and CSA strain and reached steady state following a greater number of contractions (5 contractions) in MAT compared to the contralateral tendon (3 contractions). Further, free tendon CSA and volume strained more in MAT than contralateral tendon from the first contraction, whereas free AT longitudinal strain was not greater than the contralateral tendon until the fourth contraction. Volume loss from the tendon core therefore preceded the greater longitudinal strain in MAT. Overall, these findings suggest that the tendinopathic free AT experiences an exaggerated longitudinal and transverse strain response under repeated loading that is underpinned by an altered interaction between solid and fluid tendon matrix components. These alterations are indicative of accentuated poroelasticity and an altered local stress-strain environment within the tendinopathic free tendon matrix, which could affect tendon remodelling via mechanobiological pathways.
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Affiliation(s)
- Leila Nuri
- School of Allied Health Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Steven J. Obst
- School of Health, Medical and Applied Sciences, Central Queensland University, Bundaberg, Queensland, Australia
| | - Richard Newsham-West
- School of Allied Health Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Rod S. Barrett
- School of Allied Health Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
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23
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Connizzo BK, Adams SM, Adams TH, Birk DE, Soslowsky LJ. Collagen V expression is crucial in regional development of the supraspinatus tendon. J Orthop Res 2016; 34:2154-2161. [PMID: 28005290 PMCID: PMC5189919 DOI: 10.1002/jor.23246] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/23/2016] [Indexed: 02/04/2023]
Abstract
Manipulations in cell culture and mouse models have demonstrated that reduction of collagen V results in altered fibril structure and matrix assembly. A tissue-dependent role for collagen V in determining mechanical function was recently established, but its role in determining regional properties has not been addressed. The objective of this study was to define the role(s) of collagen V expression in establishing the site-specific properties of the supraspinatus tendon. The insertion and midsubstance of tendons from wild type, heterozygous and tendon/ligament-specific null mice were assessed for crimp morphology, fibril morphology, cell morphology, as well as total collagen and pyridinoline cross-link (PYD) content. Fibril morphology was altered at the midsubstance of both groups with larger, but fewer, fibrils and no change in cell morphology or collagen compared to the wild type controls. In contrast, a significant disruption of fibril assembly was observed at the insertion site of the null group with the presence of structurally aberrant fibrils. Alterations were also present in cell density and PYD content. Altogether, these results demonstrate that collagen V plays a crucial role in determining region-specific differences in mouse supraspinatus tendon structure. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2154-2161, 2016.
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Affiliation(s)
- Brianne K. Connizzo
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 36th and Hamilton Walk, Philadelphia, PA, 19104-6081
| | - Sheila M. Adams
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612
| | - Thomas H. Adams
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612
| | - David E. Birk
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612
| | - Louis J. Soslowsky
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 36th and Hamilton Walk, Philadelphia, PA, 19104-6081
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24
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Nuri L, Obst SJ, Newsham-West R, Barrett RS. Regional three-dimensional deformation of human Achilles tendon during conditioning. Scand J Med Sci Sports 2016; 27:1263-1272. [DOI: 10.1111/sms.12742] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2016] [Indexed: 12/15/2022]
Affiliation(s)
- L. Nuri
- School of Allied Health Sciences; Menzies Health Institute Queensland; Griffith University; Gold Coast Queensland Australia
| | - S. J. Obst
- School of Allied Health Sciences; Menzies Health Institute Queensland; Griffith University; Gold Coast Queensland Australia
| | - R. Newsham-West
- School of Allied Health Sciences; Menzies Health Institute Queensland; Griffith University; Gold Coast Queensland Australia
| | - R. S. Barrett
- School of Allied Health Sciences; Menzies Health Institute Queensland; Griffith University; Gold Coast Queensland Australia
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25
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Dutov P, Antipova O, Varma S, Orgel JPRO, Schieber JD. Measurement of Elastic Modulus of Collagen Type I Single Fiber. PLoS One 2016; 11:e0145711. [PMID: 26800120 PMCID: PMC4723153 DOI: 10.1371/journal.pone.0145711] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 12/08/2015] [Indexed: 12/16/2022] Open
Abstract
Collagen fibers are the main components of the extra cellular matrix and the primary contributors to the mechanical properties of tissues. Here we report a novel approach to measure the longitudinal component of the elastic moduli of biological fibers under conditions close to those found in vivo and apply it to type I collagen from rat tail tendon. This approach combines optical tweezers, atomic force microscopy, and exploits Euler-Bernoulli elasticity theory for data analysis. This approach also avoids drying for measurements or visualization, since samples are freshly extracted. Importantly, strains are kept below 0.5%, which appear consistent with the linear elastic regime. We find, surprisingly, that the longitudinal elastic modulus of type I collagen cannot be represented by a single quantity but rather is a distribution that is broader than the uncertainty of our experimental technique. The longitudinal component of the single-fiber elastic modulus is between 100 MPa and 360 MPa for samples extracted from different rats and/or different parts of a single tail. Variations are also observed in the fibril-bundle/fibril diameter with an average of 325±40 nm. Since bending forces depend on the diameter to the fourth power, this variation in diameter is important for estimating the range of elastic moduli. The remaining variations in the modulus may be due to differences in composition of the fibril-bundles, or the extent of the proteoglycans constituting fibril-bundles, or that some single fibrils may be of fibril-bundle size.
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Affiliation(s)
- Pavel Dutov
- Center For Molecular Study Of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, United States of America.,Chemical and Biological Engineering Department, Illinois Institute of Technology, Chicago, IL, United States of America
| | - Olga Antipova
- Center For Molecular Study Of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, United States of America.,Departments of, Biology, Physics and Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States of America.,BioCAT, Sector 18, APS/Argonne National Laboratory, 9700 S. Cass Ave. Argonne, IL, United States of America
| | - Sameer Varma
- Department of Cell Biology, Microbiology and Molecular Biology, Department of Physics, University of South Florida, Tampa, FL, United States of America
| | - Joseph P R O Orgel
- Center For Molecular Study Of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, United States of America.,Departments of, Biology, Physics and Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States of America.,BioCAT, Sector 18, APS/Argonne National Laboratory, 9700 S. Cass Ave. Argonne, IL, United States of America
| | - Jay D Schieber
- Center For Molecular Study Of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, United States of America.,Chemical and Biological Engineering Department, Illinois Institute of Technology, Chicago, IL, United States of America.,Department of Physics, Illinois Institute of Technology, Chicago, IL, United States of America
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26
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Abstract
BACKGROUND The Achilles tendon is the strongest tendon in the human body. The incidence of Achilles tendon ruptures appears to be increasing. OBJECTIVES The aim of this review was to systematically summarize predictors influencing Achilles tendon rupture (ATR) risk. METHODS A systematic literature search was performed of reported determinants influencing the ATR risk. Studies were eligible if there was: (i) description of determinants predicting ATR; (ii) an outcome defined as ATR; (iii) any study design with at least ten adults included with ATR; (iv) use of statistical tests regarding differences between patients with an ATR and healthy controls; (v) a full text article available; (vi) an article written in English, German or Dutch. Quality assessment was done using a standardized criteria set. Best-evidence synthesis was performed. RESULTS We included 31 studies, of which two (6.5%) were considered high-quality studies. Moderate evidence was found for increased ATR risk and decreased fibril size of Achilles tendon. CONCLUSION Based on the results of this systematic review there is moderate evidence that decreased tendon fibril size increases the ATR risk. There is limited evidence for many other factors, some of which are modifiable, such as increased body weight, oral corticosteroid use and quinolone use and living in an urban area, and therefore may be of interest in future studies. Furthermore, these results showed that more high-quality studies are needed for evaluating the determinants influencing the ATR risk.
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Affiliation(s)
- Femke M A P Claessen
- Department of Orthopaedic Surgery, Erasmus MC, University Medical Centre Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
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Lomas A, Ryan C, Sorushanova A, Shologu N, Sideri A, Tsioli V, Fthenakis G, Tzora A, Skoufos I, Quinlan L, O'Laighin G, Mullen A, Kelly J, Kearns S, Biggs M, Pandit A, Zeugolis D. The past, present and future in scaffold-based tendon treatments. Adv Drug Deliv Rev 2015; 84:257-77. [PMID: 25499820 DOI: 10.1016/j.addr.2014.11.022] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 11/08/2014] [Accepted: 11/12/2014] [Indexed: 02/07/2023]
Abstract
Tendon injuries represent a significant clinical burden on healthcare systems worldwide. As the human population ages and the life expectancy increases, tendon injuries will become more prevalent, especially among young individuals with long life ahead of them. Advancements in engineering, chemistry and biology have made available an array of three-dimensional scaffold-based intervention strategies, natural or synthetic in origin. Further, functionalisation strategies, based on biophysical, biochemical and biological cues, offer control over cellular functions; localisation and sustained release of therapeutics/biologics; and the ability to positively interact with the host to promote repair and regeneration. Herein, we critically discuss current therapies and emerging technologies that aim to transform tendon treatments in the years to come.
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28
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Peralta L, Rus G, Bochud N, Molina FS. Mechanical assessment of cervical remodelling in pregnancy: insight from a synthetic model. J Biomech 2015; 48:1557-65. [PMID: 25766389 DOI: 10.1016/j.jbiomech.2015.02.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 02/15/2015] [Indexed: 11/16/2022]
Abstract
During the gestation and the cervical remodelling, several changes occur progressively in the structure of the tissue. An increase in the hydration, disorganisation of collagen network and decrease in elasticity can be observed. The collagen structure disorganisation is particularly complex: collagen fibres turn thicker and more wavy as the gestation progresses in a transition from relatively straight fibres to wavy fibres, while pores between collagen fibres become larger and separated. Shear wave elastography is a promising but not yet fully understood tool to assess these structural changes and the cervix׳s ability to dilate. To this end, a numerical histo-mechanical model is proposed in the present study, which aims at linking variations in the microscopic histo-biomechanical processes with shear wave propagation characteristics. Parametric simulations are carried out for a broad range of mechanical and geometrical parameters. Results show a direct relationship between the histological and morphological changes during pregnancy and the viscoelastic behaviour of the tissue.
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Affiliation(s)
- L Peralta
- Department of Structural Mechanics, University of Granada, Politécnico de Fuentenueva, 18071 Granada, Spain.
| | - G Rus
- Department of Structural Mechanics, University of Granada, Politécnico de Fuentenueva, 18071 Granada, Spain
| | - N Bochud
- Department of Structural Mechanics, University of Granada, Politécnico de Fuentenueva, 18071 Granada, Spain
| | - F S Molina
- Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynecology, San Cecilio University Hospital (HUSC), Granada, Spain
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29
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Herchenhan A, Bayer ML, Eliasson P, Magnusson SP, Kjaer M. Insulin-like growth factor I enhances collagen synthesis in engineered human tendon tissue. Growth Horm IGF Res 2015; 25:13-19. [PMID: 25281191 DOI: 10.1016/j.ghir.2014.09.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 08/06/2014] [Accepted: 09/11/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVE Isolated human tendon cells form 3D tendon constructs that demonstrate collagen fibrillogenesis and feature structural similarities to tendon when cultured under tensile load. The exact role of circulating growth factors for collagen formation in tendon is sparsely examined. We investigated the influence of insulin-like growth factor I (IGF-I) on tendon construct formation in 3D cell culture. DESIGN Tendon constructs were grown in 0.5 or 10% FBS with or without IGF-I (250 mg/ml) supplementation. Collagen content (fluorometric), mRNA levels (PCR) and fibril diameter (transmission electron microscopy) were determined at 7, 10, 14, 21 and 28 days. RESULTS IGF-I revealed a stimulating effect on fibril diameter (up to day 21), mRNA for collagen (to day 28), tenomodulin (to day 28) and scleraxis (at days 10 and 14), and on overall collagen content. 10% FBS diminished the development of fibril diameter (day 14), collagen content (at days 21 and 28) and mRNA expression for collagen, tenomodulin and scleraxis. CONCLUSION IGF-I supplementation promotes early onset of tensile load induced collagen formation and tendon structural arrangement, whereas the FBS concentration routinely used in cultures diminishes collagen expression, collagen content and fibril formation.
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Affiliation(s)
- Andreas Herchenhan
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Bispebjerg Bakke 23, Building 8, 2nd floor, 2400 Copenhagen, Denmark; Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
| | - Monika L Bayer
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Bispebjerg Bakke 23, Building 8, 2nd floor, 2400 Copenhagen, Denmark; Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Pernilla Eliasson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Bispebjerg Bakke 23, Building 8, 2nd floor, 2400 Copenhagen, Denmark; Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - S Peter Magnusson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Bispebjerg Bakke 23, Building 8, 2nd floor, 2400 Copenhagen, Denmark; Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Bispebjerg Bakke 23, Building 8, 2nd floor, 2400 Copenhagen, Denmark; Centre for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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30
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Legerlotz K, Dorn J, Richter J, Rausch M, Leupin O. Age-dependent regulation of tendon crimp structure, cell length and gap width with strain. Acta Biomater 2014; 10:4447-55. [PMID: 24907659 DOI: 10.1016/j.actbio.2014.05.029] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/19/2014] [Accepted: 05/23/2014] [Indexed: 12/13/2022]
Abstract
The black-and-white patterning of tendon fascicles when visualized by light microscopy, also known as crimp, is a well-known feature of fiber-forming collagens. However, not much is known about its development, function and response to strain. The objective of this study is to investigate the interaction of tenocyte and crimp morphology as well as their changes with increasing age and acute strain. In contrast to previous studies, which used indirect measures, such as polarized light, to investigate the crimp structure, this study visualizes internal crimp structure in three dimensions without freezing, sectioning, staining or fixing the tissue, via two-photon imaging of green fluorescent protein expressing cells within mouse tail tendon fascicles. This technique further allows straining of the live tissue while visualizing changes in crimp morphology and cell shape with increasing specimen length. Combining this novel microscopy technique with computational image and data analysis revealed a complex relationship between tenocytes and the extracellular matrix that evolves with increasing age. While the reduction of crimping with strain was observed as expected, most of the crimps were gone at 0-1% strain already. Even relatively low strains of 3% led to pronounced changes in the crimp structure after relaxation, particularly in the young animals, which could not be seen with bright-field imaging. Cell length and gap width increased with strain. However, while the cells were able to return to their original length even after high strains of 6%, the gaps between the cells widened, which may imply modified cell-cell communication after overstretching.
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31
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Tilley JMR, Murphy RJ, Chaudhury S, Czernuszka JT, Carr AJ. Effect of tear size, corticosteroids and subacromial decompression surgery on the hierarchical structural properties of torn supraspinatus tendons. Bone Joint Res 2014; 3:252-61. [PMID: 25106417 PMCID: PMC4127658 DOI: 10.1302/2046-3758.38.2000251] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 03/05/2014] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES The effects of disease progression and common tendinopathy treatments on the tissue characteristics of human rotator cuff tendons have not previously been evaluated in detail owing to a lack of suitable sampling techniques. This study evaluated the structural characteristics of torn human supraspinatus tendons across the full disease spectrum, and the short-term effects of subacromial corticosteroid injections (SCIs) and subacromial decompression (SAD) surgery on these structural characteristics. METHODS Samples were collected inter-operatively from supraspinatus tendons containing small, medium, large and massive full thickness tears (n = 33). Using a novel minimally invasive biopsy technique, paired samples were also collected from supraspinatus tendons containing partial thickness tears either before and seven weeks after subacromial SCI (n = 11), or before and seven weeks after SAD surgery (n = 14). Macroscopically normal subscapularis tendons of older patients (n = 5, mean age = 74.6 years) and supraspinatus tendons of younger patients (n = 16, mean age = 23.3) served as controls. Ultra- and micro-structural characteristics were assessed using atomic force microscopy and polarised light microscopy respectively. RESULTS Significant structural differences existed between torn and control groups. Differences were identifiable early in the disease spectrum, and increased with increasing tear size. Neither SCI nor SAD surgery altered the structural properties of partially torn tendons seven weeks after treatment. CONCLUSIONS These findings may suggest the need for early clinical intervention strategies for torn rotator cuff tendons in order to prevent further degeneration of the tissue as tear size increases. Further work is required to establish the long-term abilities of SCI and SAD to prevent, and even reverse, such degeneration. Cite this article: Bone Joint Res 2014;3:252-61.
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Affiliation(s)
- J M R Tilley
- University of Oxford, Department of Materials, Oxford OX1 3PH, UK
| | - R J Murphy
- Institute of Musculoskeletal Sciences, University of Oxford, Old Road, Oxford, OX3 7LD, UK
| | - S Chaudhury
- Institute of Musculoskeletal Sciences, University of Oxford, Old Road, Oxford, OX3 7LD, UK
| | - J T Czernuszka
- University of Oxford, Department of Materials, Oxford OX1 3PH, UK
| | - A J Carr
- Institute of Musculoskeletal Sciences, University of Oxford, Old Road, Oxford, OX3 7LD, UK
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32
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Couppé C, Svensson RB, Grosset JF, Kovanen V, Nielsen RH, Olsen MR, Larsen JO, Praet SFE, Skovgaard D, Hansen M, Aagaard P, Kjaer M, Magnusson SP. Life-long endurance running is associated with reduced glycation and mechanical stress in connective tissue. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9665. [PMID: 24997017 PMCID: PMC4150896 DOI: 10.1007/s11357-014-9665-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 06/18/2014] [Indexed: 05/07/2023]
Abstract
Life-long regular endurance exercise is known to counteract the deterioration of cardiovascular and metabolic function and overall mortality. Yet it remains unknown if life-long regular endurance exercise can influence the connective tissue accumulation of advanced glycation endproducts (AGEs) that is associated with aging and lifestyle-related diseases. We therefore examined two groups of healthy elderly men: 15 master athletes (64 ± 4 years) who had been engaged in life-long endurance running and 12 old untrained (66 ± 4 years) together with two groups of healthy young men; ten young athletes matched for running distance (26 ± 4 years), and 12 young untrained (24 ± 3 years). AGE cross-links (pentosidine) of the patellar tendon were measured biochemically, and in the skin, it was assessed by a fluorometric method. In addition, we determined mechanical properties and microstructure of the patellar tendon. Life-long regular endurance runners (master athletes) had a 21 % lower AGE cross-link density compared to old untrained. Furthermore, both master athletes and young athletes displayed a thicker patellar tendon. These cross-sectional data suggest that life-long regular endurance running can partly counteract the aging process in connective tissue by reducing age-related accumulation of AGEs. This may not only benefit skin and tendon but also other long-lived protein tissues in the body. Furthermore, it appears that endurance running yields tendon tissue hypertrophy that may serve to lower the stress on the tendon and thereby reduce the risk of injury.
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Affiliation(s)
- Christian Couppé
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Bldg. 8, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark,
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33
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Shepherd JH, Screen HRC. Fatigue loading of tendon. Int J Exp Pathol 2013; 94:260-70. [PMID: 23837793 DOI: 10.1111/iep.12037] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 06/12/2013] [Indexed: 12/28/2022] Open
Abstract
Tendon injuries, often called tendinopathies, are debilitating and painful conditions, generally considered to develop as a result of tendon overuse. The aetiology of tendinopathy remains poorly understood, and whilst tendon biopsies have provided some information concerning tendon appearance in late-stage disease, there is still little information concerning the mechanical and cellular events associated with disease initiation and progression. Investigating this in situ is challenging, and numerous models have been developed to investigate how overuse may generate tendon fatigue damage and how this may relate to tendinopathy conditions. This article aims to review these models and our current understanding of tendon fatigue damage. We review the strengths and limitations of different methodologies for characterizing tendon fatigue, considering in vitro methods that adopt both viable and non-viable samples, as well as the range of different in vivo approaches. By comparing data across model systems, we review the current understanding of fatigue damage development. Additionally, we compare these findings with data from tendinopathic tissue biopsies to provide some insights into how these models may relate to the aetiology of tendinopathy. Fatigue-induced damage consistently highlights the same microstructural, biological and mechanical changes to the tendon across all model systems and also correlates well with the findings from tendinopathic biopsy tissue. The multiple testing routes support matrix damage as an important contributor to tendinopathic conditions, but cellular responses to fatigue appear complex and often contradictory.
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Affiliation(s)
- Jennifer H Shepherd
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary, University of London, London E1 4NS, UK.
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34
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Kiewiet NJ, Holthusen SM, Bohay DR, Anderson JG. Gastrocnemius recession for chronic noninsertional Achilles tendinopathy. Foot Ankle Int 2013; 34:481-5. [PMID: 23399888 DOI: 10.1177/1071100713477620] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND In patients with chronic Achilles tendinopathy, several operative techniques have been described for treatment. A case report has shown that gastrocnemius recession as treatment can normalize MRI findings and relieve clinical symptoms consistent with chronic Achilles tendinopathy. The purpose of this study was to present the results of the treatment of chronic Achilles tendinopathy with gastrocnemius recession. METHODS Of 12 patients, 8 (7 females, 1 male) who underwent gastrocnemius recession for refractory Achilles tendinopathy between July 2004 and January 2009 were available for follow-up. All patients filled out a SF-36 health survey, a foot function index, an AOFAS ankle and hindfoot scale, and a simple survey formulated by our group of investigators. Of the 8 patients, 7 were available to return for clinical assessment. Patients had an average age of 49.9 years (SD = 11.6) at the time of surgery and average time of follow-up was 34.6 months (SD = 18.1). RESULTS The mean pain score (VAS 0-10 scale) significantly decreased from 7.3 (SD = 1.7) preoperatively to 1 (SD = 1.8) postoperatively at the time of follow-up (P < .001). The mean AOFAS ankle and hindfoot score was 94.4 (SD = 9.8), which was significantly improved when compared with previously published scores for patients who underwent Achilles debridement with FHL transfer (P = .007). All 8 categories on the SF-36 health survey showed no significant difference with published data for US population values and previously published data for patients who underwent FHL transfer. CONCLUSION Gastrocnemius recession for the treatment of refractory Achilles tendinopathy was a viable treatment option following the failure of nonoperative management. All 8 of our patients had excellent pain relief, good clinical outcome, and were satisfied at the time of follow-up.
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35
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Hansen M, Couppe C, Hansen CSE, Skovgaard D, Kovanen V, Larsen JO, Aagaard P, Magnusson SP, Kjaer M. Impact of oral contraceptive use and menstrual phases on patellar tendon morphology, biochemical composition, and biomechanical properties in female athletes. J Appl Physiol (1985) 2013; 114:998-1008. [PMID: 23429870 DOI: 10.1152/japplphysiol.01255.2012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Sex differences exist with regards to ligament and tendon injuries. Lower collagen synthesis has been observed in exercising women vs. men, and in users of oral contraceptives (OC) vs. nonusers, but it is unknown if OC will influence tendon biomechanics of women undergoing regular training. Thirty female athletes (handball players, 18-30 yr) were recruited: 15 long-term users of OC (7.0 ± 0.6 yr) and 15 nonusers (>5 yr). Synchronized values of patellar tendon elongation (obtained by ultrasonography) and tendon force were sampled during ramped isometric knee extensor maximum voluntary contraction to estimate mechanical tendon properties. Furthermore, tendon cross-sectional area and length were measured from MRI images, and tendon biopsies were obtained for analysis of tendon fibril characteristics and collagen cross-linking. Overall, no difference in tendon biomechanical properties, tendon fibril characteristics, or collagen cross-linking was observed between the OC users and nonusers, or between the different phases of the menstrual cycle. In athletes, tendon cross-sectional area in the preferred jumping leg tended to be larger than that in the contralateral leg (P = 0.09), and a greater absolute (P = 0.01) and normalized tendon stiffness (P = 0.02), as well as a lower strain (P = 0.04), were observed in the jumping leg compared with the contralateral leg. The results indicate that long-term OC use or menstrual phases does not influence structure or mechanical properties of the patellar tendon in female team handball athletes.
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Affiliation(s)
- Mette Hansen
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital, and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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36
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Hansen P, Kovanen V, Hölmich P, Krogsgaard M, Hansson P, Dahl M, Hald M, Aagaard P, Kjaer M, Magnusson SP. Micromechanical properties and collagen composition of ruptured human achilles tendon. Am J Sports Med 2013; 41:437-43. [PMID: 23263296 DOI: 10.1177/0363546512470617] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive. HYPOTHESIS Ruptured human Achilles tendon displays inferior biomechanical properties and altered collagen composition compared with noninjured tendon. STUDY DESIGN Controlled laboratory study. METHODS Biopsy specimens were obtained at the rupture site and the noninjured part of the tendon (internal controls) in 17 patients with acute Achilles tendon rupture. Age- and weight-matched human cadaveric Achilles tendons (external controls) were also obtained. Tendon samples were tested micromechanically and biochemically. RESULTS The mean Young modulus was lower (P < .01) in ruptured (256.7 ± 100.8 MPa) and internal control tendon (262.4 ± 111.5 MPa) compared with external control tendon (512.9 ± 209.6 MPa; P < .01), whereas failure strength did not display similar differences (P = .06-.16). Collagen content, lysyl pyridinoline (LP), hydroxylysyl pyridinoline (HP), and pentosidine (PENT) did not display regional differences between ruptured and noninjured tendon. However, collagen content was less in ruptured (0.457 ± 0.093 mg/mg) and noninjured tendon (0.476 ± 0.072 mg/mg) compared with external control tendon (0.585 ± 0.044 mg/mg, P < .001). Pentosidine was similar in all tendon samples and was positively related to age in all samples (r2 = 0.44-0.72, P < .05). Collagen content was positively related to failure stress but only in ruptured samples (r2 = 0.36; P < .05). HP, LP, and PENT content were unrelated to failure stress and Young modulus in ruptured, noninjured, and cadaveric tendon. CONCLUSION These data imply that there may be a mechanical weakening of the tendon and that a reduced collagen content may be related to the pathophysiological characteristics of Achilles tendon rupture. CLINICAL RELEVANCE Earlier studies have demonstrated that specific training regimens to treat tendon injury can improve tendon composition and mechanical properties. This study supports the notion that treatment measures should aim to increase tendon collagen content and improve micromechanical quality of the tendon matrix.
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Affiliation(s)
- Philip Hansen
- Institute of Sports Medicine Copenhagen, Bispebjerg Bakke 23, Building 8, 1st Floor, DK-2400 Copenhagen, Denmark
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Herchenhan A, Bayer ML, Svensson RB, Magnusson SP, Kjaer M. In vitro tendon tissue development from human fibroblasts demonstrates collagen fibril diameter growth associated with a rise in mechanical strength. Dev Dyn 2012; 242:2-8. [DOI: 10.1002/dvdy.23896] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2012] [Indexed: 11/11/2022] Open
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Patterson-Kane JC, Becker DL, Rich T. The pathogenesis of tendon microdamage in athletes: the horse as a natural model for basic cellular research. J Comp Pathol 2012; 147:227-47. [PMID: 22789861 DOI: 10.1016/j.jcpa.2012.05.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 05/14/2012] [Indexed: 12/30/2022]
Abstract
The equine superficial digital flexor tendon (SDFT) is a frequently injured structure that is functionally and clinically equivalent to the human Achilles tendon (AT). Both act as critical energy-storage systems during high-speed locomotion and can accumulate exercise- and age-related microdamage that predisposes to rupture during normal activity. Significant advances in understanding of the biology and pathology of exercise-induced tendon injury have occurred through comparative studies of equine digital tendons with varying functions and injury susceptibilities. Due to the limitations of in-vivo work, determination of the mechanisms by which tendon cells contribute to and/or actively participate in the pathogenesis of microdamage requires detailed cell culture modelling. The phenotypes induced must ultimately be mapped back to the tendon tissue environment. The biology of tendon cells and their matrix, and the pathological changes occurring in the context of early injury in both horses and people are reviewed, with a particular focus on the use of various tendon cell and tissue culture systems to model these events.
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Affiliation(s)
- J C Patterson-Kane
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
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Carroll CC, Whitt JA, Peterson A, Gump BS, Tedeschi J, Broderick TL. Influence of acetaminophen consumption and exercise on Achilles tendon structural properties in male Wistar rats. Am J Physiol Regul Integr Comp Physiol 2012; 302:R990-5. [DOI: 10.1152/ajpregu.00659.2011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chronic consumption of acetaminophen (APAP) during exercise training leads to a reduction in tendon stiffness and modulus compared with a placebo. We explored whether this effect could be due to a reduction in tendon collagen content or cross-linking. Ten-week-old male Wistar rats ( n = 50) were divided into placebo or APAP groups and into sedentary or treadmill-exercised groups. APAP (200 mg/kg) or saline was administered once daily by oral gavage. Rats in the exercise groups ran on a treadmill 5 days per week for 8 wk with progression to 60 min per day, 20 m/min, and 8° incline. After 8 wk, lyophilized Achilles tendon samples were assayed for the collagen-specific amino acid hydroxyproline and cross-linking [hydroxylyslpyridinoline (HP)] content by high-performance liquid chromatrography. Collagen content was not influenced by exercise or APAP ( P > 0.05). Compared with placebo, tendon water content was 7% ( P = 0.006, main effect) lower in animals consuming APAP (placebo: 54.79 ± 0.8%, APAP: 50.89 ± 1.2%). HP in the Achilles tendon was 36% greater (sedentary: 141 ± 15, exercise: 204 ± 26 mmol/mol collagen) in the exercise-trained rats independent of drug treatment ( P = 0.020, main effect). Independent of exercise, HP content was 33% lower ( P = 0.032, main effect) in the animals consuming APAP (placebo: 195 ± 21, APAP: 140 ± 19 mmol/mol collagen). Our data suggests that chronic consumption of APAP results in a reduction in collagen cross-linking and a loss of tissue water independent of chronic exercise. This reduction in cross-linking and water content could contribute to the decrease in tendon stiffness noted in humans chronically consuming APAP.
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Affiliation(s)
- Chad C. Carroll
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
| | - Jamie A. Whitt
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
| | - Amity Peterson
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
| | - Brian S. Gump
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
| | - Jamie Tedeschi
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
| | - Tom L. Broderick
- Department of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona
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J P, U F, K Q, JO L, P S, K H, M K, H L. Local biochemical and morphological differences in human Achilles tendinopathy: a case control study. BMC Musculoskelet Disord 2012; 13:53. [PMID: 22480275 PMCID: PMC3341204 DOI: 10.1186/1471-2474-13-53] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 04/05/2012] [Indexed: 01/12/2023] Open
Abstract
Background The incidence of Achilles tendinopathy is high and underlying etiology as well as biochemical and morphological pathology associated with the disease is largely unknown. The aim of the present study was to describe biochemical and morphological differences in chronic Achilles tendinopathy. The expressions of growth factors, inflammatory mediators and tendon morphology were determined in both chronically diseased and healthy tendon parts. Methods Thirty Achilles tendinopathy patients were randomized to an expression-study (n = 16) or a structural-study (n = 14). Biopsies from two areas in the Achilles tendon were taken and structural parameters: fibril density, fibril size, volume fraction of cells and the nucleus/cytoplasm ratio of cells were determined. Further gene expressions of various genes were analyzed. Results Significantly smaller collagen fibrils and a higher volume fraction of cells were observed in the tendinopathic region of the tendon. Markers for collagen and its synthesis collagen 1, collagen 3, fibronectin, tenascin-c, transforming growth factor-β fibromodulin, and markers of collagen breakdown matrix metalloproteinase-2, matrix metalloproteinase-9 and metallopeptidase inhibitor-2 were significantly increased in the tendinopathic region. No altered expressions of markers for fibrillogenesis, inflammation or wound healing were observed. Conclusion The present study indicates that an increased expression of factors stimulating the turnover of connective tissue is present in the diseased part of tendinopathic tendons, associated with an increased number of cells in the injured area as well as an increased number of smaller and thinner fibrils in the diseased tendon region. As no fibrillogenesis, inflammation or wound healing could be detected, the present data supports the notion that tendinopathy is an ongoing degenerative process. Trial registration Current Controlled Trials ISRCTN20896880
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Svensson RB, Hassenkam T, Hansen P, Kjaer M, Magnusson SP. Tensile force transmission in human patellar tendon fascicles is not mediated by glycosaminoglycans. Connect Tissue Res 2011; 52:415-21. [PMID: 21453063 DOI: 10.3109/03008207.2010.551569] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Correct mechanical function of tendons is essential to human physiology and therefore the mechanical properties of tendon have been a subject of research for many decades now. However, one of the most fundamental questions remains unanswered: How is load transmitted through the tendon? It has been suggested that the proteoglycan-associated glycosaminoglycans (GAGs) found on the surface of the collagen fibrils may be an important transmitter of load, but existing results are ambiguous and have not investigated human tendons. We have used a small-scale mechanical testing system to measure the mechanical properties of fascicles from human patellar tendon at two different deformation rates before and after removal of GAGs by treatment with chondroitinase ABC. Efficiency of enzyme treatment was quantified using dimethylmethylene blue assay. Removal of at least 79% of the GAGs did not significantly change the tendon modulus, relative energy dissipation, peak stress, or peak strain. The effect of deformation rate was not modulated by the treatment either, indicating no effect on viscosity. These results suggest that GAGs cannot be considered mediators of tensile force transmission in the human patellar tendon, and as such, force transmission must either take place through other matrix components or the fibrils must be mechanically continuous at least to the tested length of 7 mm.
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Affiliation(s)
- René B Svensson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital and Center for Healthy Aging, University of Copenhagen, Denmark
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Experimental investigation of collagen waviness and orientation in the arterial adventitia using confocal laser scanning microscopy. Biomech Model Mechanobiol 2011; 11:461-73. [DOI: 10.1007/s10237-011-0325-z] [Citation(s) in RCA: 665] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 06/20/2011] [Indexed: 11/26/2022]
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Wang VM, Wang F, McNickle AG, Friel NA, Yanke AB, Chubinskaya S, Romeo AA, Verma NN, Cole BJ. Medial versus lateral supraspinatus tendon properties: implications for double-row rotator cuff repair. Am J Sports Med 2010; 38:2456-63. [PMID: 20929937 PMCID: PMC3772634 DOI: 10.1177/0363546510376817] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Rotator cuff repair retear rates range from 25% to 90%, necessitating methods to improve repair strength. Although numerous laboratory studies have compared single-row with double-row fixation properties, little is known regarding regional (ie, medial vs lateral) suture retention properties in intact and torn tendons. HYPOTHESIS A torn supraspinatus tendon will have reduced suture retention properties on the lateral aspect of the tendon compared with the more medial musculotendinous junction. STUDY DESIGN Controlled laboratory study. METHODS Human supraspinatus tendons (torn and intact) were randomly assigned for suture retention mechanical testing, ultrastructural collagen fibril analysis, or histologic testing after suture pullout testing. For biomechanical evaluation, sutures were placed either at the musculotendinous junction (medial) or 10 mm from the free margin (lateral), and tendons were elongated to failure. Collagen fibril assessments were performed using transmission electron microscopy. RESULTS Intact tendons showed no regional differences with respect to suture retention properties. In contrast, among torn tendons, the medial region exhibited significantly higher stiffness and work values relative to the lateral region. For the lateral region, work to 10-mm displacement (1592 ± 261 N-mm) and maximum load (265 ± 44 N) for intact tendons were significantly higher (P < .05) than that of torn tendons (1086 ± 388 N-mm and 177 ± 71 N, respectively). For medial suture placement, maximum load, stiffness, and work of intact and torn tendons were similar (P > .05). Regression analyses for the intact and torn groups revealed generally low correlations between donor age and the 3 biomechanical indices. For both intact and torn tendons, the mean fibril diameter and area density were greater in the medial region relative to the lateral (P ≤ .05). In the lateral tendon, but not the medial region, torn specimens showed a significantly lower fibril area fraction (48.3% ± 3.8%) than intact specimens (56.7% ± 3.6%, P < .05). CONCLUSION Superior pullout resistance of medially placed sutures may provide a strain shielding effect for the lateral row after double-row repair. Larger diameter collagen fibrils as well as greater fibril area fraction in the medial supraspinatus tendon may provide greater resistance to suture migration. CLINICAL RELEVANCE While clinical factors such as musculotendinous integrity warrant strong consideration for surgical decision making, the present ultrastructural and biomechanical results appear to provide a scientific rationale for double-row rotator cuff repair where sutures are placed more medially at the muscle-tendon junction.
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Affiliation(s)
| | - FanChia Wang
- Rush University Medical Center, Chicago, Illinois
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Doessing S, Holm L, Heinemeier KM, Feldt-Rasmussen U, Schjerling P, Qvortrup K, Larsen JO, Nielsen RH, Flyvbjerg A, Kjaer M. GH and IGF1 levels are positively associated with musculotendinous collagen expression: experiments in acromegalic and GH deficiency patients. Eur J Endocrinol 2010; 163:853-62. [PMID: 20858702 DOI: 10.1530/eje-10-0818] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Disproportionate growth of musculoskeletal tissue is a major cause of morbidity in both acromegalic (ACRO) and GH-deficient (GHD) patients. GH/IGF1 is likely to play an important role in the regulation of tendon and muscle collagen. We hypothesized that the local production of collagen is associated with the level of GH/IGF1. DESIGN AND METHODS As primary outcomes, collagen mRNA expression and collagen protein fractional synthesis rate (FSR) were determined locally in skeletal muscle and tendon in nine ACRO and nine GHD patients. Moreover, muscle myofibrillar protein synthesis and tendon collagen morphology were determined. RESULTS AND CONCLUSIONS Muscle collagen I and III mRNA expression was higher in ACRO patients versus GHD patients (P<0.05), whereas collagen protein FSR did not differ significantly between ACRO and GHD patients in muscle (P=0.21) and tendon (P=0.15). IGF1Ea and IGF1Ec mRNA expression in muscle was higher in ACRO patients versus GHD patients (P<0.01). Muscle IGF1Ea mRNA expression correlated positively with collagen I mRNA expression (P<0.01). Tendon collagen fibrillar area tended to be higher in GHD patients relative to ACRO patients (P=0.07). Thus, we observed a higher expression for collagen and IGF1 mRNA in local musculotendinous tissue in ACRO patients relative to GHD patients. Moreover, there was a tendency towards a higher collagen protein FSR and a smaller collagen fibril diameter in ACRO patients relative to GHD patients. The results indicate a collagen-stimulating role of local IGF1 in human connective tissue and add to the understanding of musculoskeletal pathology in patients with either high or low GH/IGF1 axis activity.
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Affiliation(s)
- Simon Doessing
- Department of Orthopaedic Surgery M, Faculty of Health Sciences, Institute of Sports Medicine, Bispebjerg Hospital and Centre for Healthy Aging, University of Copenhagen, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
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Abstract
Qualitative analysis of meniscal attachments from five human knees was completed using scanning electron microscopy (SEM). In addition, quantitative analysis to determine the collagen crimping angle and length in each attachment was done. Morphological differences were revealed between the distinct zones of the attachments from the meniscus transition to the bony insertion. Collagen fibers near to the meniscus appeared inhomogeneous in a radial cross-section view. The sheath surrounding the fibers seemed loose compared with the membrane wrapping around the fibers in the menisci. The midsubstance of human meniscal attachments was composed of collagen fibers running parallel to the longitudinal axis, with a few fibers running obliquely, and others transversely. The bony insertion showed that the crimping pattern vanishes as the collagen fibers approach the fibrocartilagenous enthesis. There were no differences between attachments for crimping angle or length. Collagen crimping angles for all attachments were similar with values of approximately 22°. Crimp length values tended to be smaller for the medial attachments (MA: 4.76 ± 1.95 μm; MP: 3.72 ± 2.31 μm) and higher for the lateral (LA: 6.49 ± 2.34 μm, LP: 6.91 ± 2.29 μm). SEM was demonstrated to be an effective method for revealing the morphology of fibrous connective tissue. The data of collagen fiber length and angle found in this study will allow for better development of microstructural models of meniscal attachments. This study will help to better understand the relation between the morphology and the architecture of collagen and the mechanical behavior of meniscal attachments.
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Affiliation(s)
- Diego F Villegas
- Department of Mechanical Engineering, Universidad del Turabo, Gurabo, Puerto Rico
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Abstract
The characteristic cells in tendons and ligaments are called tenocytes, which are responsible for the formation and turnover of the extracellular matrix. They react to external stimuli and facilitate the functional adaptation of the proteoglycan and collagen network to mechanical requirements. Via numerous cellular processes they form a complex communicating network which demonstrates coordinated directional reactions. As is common to all tissues in the human body, tendons are subject to age changes which influence the tenocytes, but additionally the structural organization and hence the function of the extracellular matrix. The function and organization of tendons are also affected by mechanical forces, as well as by various cytokines produced in the tissue and by the application of anti-inflammatory medication.
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Kongsgaard M, Qvortrup K, Larsen J, Aagaard P, Doessing S, Hansen P, Kjaer M, Magnusson SP. Fibril morphology and tendon mechanical properties in patellar tendinopathy: effects of heavy slow resistance training. Am J Sports Med 2010; 38:749-56. [PMID: 20154324 DOI: 10.1177/0363546509350915] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Patellar tendinopathy is characterized by pathologic abnormalities. Heavy slow resistance training (HSR) is effective in the management of patellar tendinopathy, but the underlying functional mechanisms remain elusive. PURPOSE To investigate fibril morphology and mechanical properties in patellar tendinopathy and the effect of HSR on these properties. STUDY DESIGN Cohort study; Level of evidence, 2. METHODS Eight male patients with patellar tendinopathy completed 12 weeks of HSR. Nine healthy subjects served as controls. Assessments were conducted at baseline and at 12 weeks. Patients assessed symptoms/function and maximal tendon pain during activity. Tendon biopsy samples were analyzed for fibril density, volume fraction, and mean fibril area. Tendon mechanical properties were assessed using force and ultrasonography samplings. RESULTS Patients improved in symptoms/function (P = .02) and maximal tendon pain during activity (P = .008). Stiffness and modulus of control and tendinopathy tendons were similar at baseline. Stiffness remained unaffected in control tendons (3487 +/- 392 to 3157 +/- 327 N/mm, P = .57) but declined in tendinopathic tendons at 12 weeks (3185 +/- 187 to 2701 +/- 201 N/mm, P = .04). At baseline, fibril volume fraction was equal, fibril density smaller (P = .03), and mean fibril area tended to be higher in tendinopathy versus controls (P = .07). Fibril morphology remained unchanged in controls but fibril density increased (70% +/- 18%, P = .02) and fibril mean area decreased (-26% +/- 21%, P = .04) in tendinopathic tendons after HSR. CONCLUSION Fibril morphology is abnormal in tendinopathy, but tendon mechanical properties are not. Clinical improvements after HSR were associated with changes in fibril morphology toward normal fibril density and mean fibril area. Heavy slow resistance training improved the clinical outcome of patellar tendinopathy, and these improvements were associated with normalization of fibril morphology, most likely due to a production of new fibrils.
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Affiliation(s)
- Mads Kongsgaard
- Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, University of Copenhagen, Denmark.
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Rigozzi S, Müller R, Snedeker JG. Collagen fibril morphology and mechanical properties of the Achilles tendon in two inbred mouse strains. J Anat 2010; 216:724-31. [PMID: 20345854 DOI: 10.1111/j.1469-7580.2010.01225.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The relationship between collagen fibril morphology and the functional behavior of tendon tissue has been investigated in numerous experimental studies. Several of these studies suggest that larger fibril radius is a primary determinant of higher tendon stiffness and strength; others have shown that factors apart from fibril radius (such as fibril-fibril interactions) may be critical to improved tendon strength. In the present study, we investigate these factors in two inbred mouse strains that are widely used in skeletal structure-function research: C57BL/6J (B6) and C3H/HeJ (C3H). The aim was to establish a quantitative baseline that will allow one to assess how regulation of tendon extracellular matrix architecture affects tensile mechanical properties. We specifically focused on collagen fibril structure and glycosaminoglycan (GAG) content--the two primary constituents of tendon by dry weight--and their potential functional interactions. For this purpose, Achilles tendons from both groups were tested to failure in tension. Tendon collagen morphology was analyzed from transmission electron microscopy images of tendon sections perpendicular to the longitudinal axis. Our results showed that the two inbred strains are macroscopically similar, but C3H mice have a higher elastic modulus (P < 0.05). Structurally, C3H mice showed a larger collagen fibril radius compared to B6 mice (96 +/- 7 nm and 80 +/- 10 nm respectively). Tendons from C3H mice also showed smaller specific fibril surface (0.015 +/- 0.001 nm nm(-2) vs. 0.017 +/- 0.003 nm nm(-2) in the B6 tendons, P < 0.05), and accordingly a lower concentration of GAGs (0.60 +/- 0.07 microg mg(-1) vs. 0.83 +/- 0.11 microg mg(-1), P < 0.05). As in other studies of tendon structure and function, larger collagen fibril radius appears to be associated with stiffer tendon, but this functional difference could also be attributed to reduced potential surface area exchange between fibrils and the surrounding proteoglycan-rich matrix, in which the hydrophilic GAG side chains may promote inter-fibril sliding. This study provides an architectural and functional baseline for a comparative murine model that can be used to investigate the genetic regulation of tendon biomechanics.
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Affiliation(s)
- S Rigozzi
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
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Hansen P, Haraldsson BT, Aagaard P, Kovanen V, Avery NC, Qvortrup K, Larsen JO, Krogsgaard M, Kjaer M, Peter Magnusson S. Lower strength of the human posterior patellar tendon seems unrelated to mature collagen cross-linking and fibril morphology. J Appl Physiol (1985) 2010; 108:47-52. [DOI: 10.1152/japplphysiol.00944.2009] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The human patellar tendon is frequently affected by tendinopathy, but the etiology of the condition is not established, although differential loading of the anterior and posterior tendon may be associated with the condition. We hypothesized that changes in fibril morphology and collagen cross-linking would parallel differences in material strength between the anterior and posterior tendon. Tendon fascicles were obtained from elective ACL surgery patients and tested micromechanically. Transmission electron microscopy was used to assess fibril morphology, and collagen cross-linking was determined by HPLC and calorimetry. Anterior fascicles were markedly stronger (peak stress: 54.3 ± 21.2 vs. 39.7 ± 21.3 MPa; P < 0.05) and stiffer (624 ± 232 vs. 362 ± 170 MPa; P < 0.01) than posterior fascicles. Notably, mature pyridinium type cross-links were less abundant in anterior fascicles (hydroxylysylpyridinoline: 0.859 ± 0.197 vs. 1.416 ± 0.250 mol/mol, P = 0.001; lysylpyridinoline: 0.023 ± 0.006 vs. 0.035 ± 0.006 mol/mol, P < 0.01), whereas pentosidine and pyrrole concentrations showed no regional differences. Fibril diameters tended to be larger in anterior fascicles (7.819 ± 2.168 vs. 4.897 ± 1.434 nm2; P = 0.10). Material properties did not appear closely related to cross-linking or fibril morphology. These findings suggest region-specific differences in mechanical, structural, and biochemical properties of the human patellar tendon.
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Affiliation(s)
- Philip Hansen
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital & Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bjarki Thor Haraldsson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital & Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Per Aagaard
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Vuokko Kovanen
- Department of Health Sciences, Biochemistry Laboratory, University of Jyväskylä, Jyväskylä, Finland
| | - Nicholas C. Avery
- Department of Clinical Veterinary Science, Matrix Biology Research Group, University of Bristol, Langford, North Somerset, United Kingdom
| | - Klaus Qvortrup
- Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Jytte Overgaard Larsen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Michael Krogsgaard
- Department of Orthopedic Surgery, Bispebjerg Hospital, Copenhagen, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital & Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - S. Peter Magnusson
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital & Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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