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Petrie MA, Dudley-Javoroski S, Johnson KA, Lee J, Dubey O, Shields RK. Low-frequency electrically induced exercise after spinal cord injury: Physiologic challenge to skeletal muscle and feasibility for long-term use. J Spinal Cord Med 2024:1-7. [PMID: 38619192 DOI: 10.1080/10790268.2024.2338295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/16/2024] Open
Abstract
CONTEXT Skeletal muscle has traditionally been considered a "force generator": necessary for purposes of locomotion, but expendable for non-ambulators who use wheelchairs, such as people with a spinal cord injury (SCI). Active skeletal muscle plays an indispensable role in regulating systemic metabolic functions, even in people with paralysis, but because of severe osteoporosis, high tetanic muscle forces induced with high frequency electrical stimulation may be risky for some individuals. The purpose of this study was to compare the physiologic muscle properties incurred by two low force/low frequency repetitive stimulation protocols (1 and 3 Hz); and, to assess the acceptability of each protocol among people with SCI. METHODS Ten individuals with chronic SCI (12.9 years) and 11 individuals without SCI (NonSCI) participated in the study. Participants received either 1 or 3 Hz stimulation to the quadriceps muscle on Day 1, then the converse on Day 2. Each session consisted of 1000 stimulus pulses. RESULTS The initial and maximum forces were similar for the 1 and 3 Hz frequencies. The fatigue index (FI) for SCI and NonSCI groups were lower (P < 0.007) for 3 Hz than for 1 Hz (0.34 ± 0.17 versus 0.65 ± 0.16 and 0.72 ± 0.14 versus 0.87 ± 0.07, respectively). CONCLUSION The 3 Hz stimulation offered the greatest physiological challenge and was perceived as more acceptable for long term use among people with SCI.
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Affiliation(s)
- Michael A Petrie
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Shauna Dudley-Javoroski
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Kristin A Johnson
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Jinhyun Lee
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Olga Dubey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Richard K Shields
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
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Crossley CB, Diamond LE, Saxby DJ, de Sousa A, Lloyd DG, Che Fornusek, Pizzolato C. Joint contact forces during semi-recumbent seated cycling. J Biomech 2024; 168:112094. [PMID: 38640830 DOI: 10.1016/j.jbiomech.2024.112094] [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: 10/06/2023] [Revised: 03/07/2024] [Accepted: 04/14/2024] [Indexed: 04/21/2024]
Abstract
Semi-recumbent cycling performed from a wheelchair is a popular rehabilitation exercise following spinal cord injury (SCI) and is often paired with functional electrical stimulation. However, biomechanical assessment of this cycling modality is lacking, even in unimpaired populations, hindering the development of personalised and safe rehabilitation programs for those with SCI. This study developed a computational pipeline to determine lower limb kinematics, kinetics, and joint contact forces (JCF) in 11 unimpaired participants during voluntary semi-recumbent cycling using a rehabilitation ergometer. Two cadences (40 and 60 revolutions per minute) and three crank powers (15 W, 30 W, and 45 W) were assessed. A rigid body model of a rehabilitation ergometer was combined with a calibrated electromyogram-informed neuromusculoskeletal model to determine JCF at the hip, knee, and ankle. Joint excursions remained consistent across all cadence and powers, but joint moments and JCF differed between 40 and 60 revolutions per minute, with peak JCF force significantly greater at 40 compared to 60 revolutions per minute for all crank powers. Poor correlations were found between mean crank power and peak JCF across all joints. This study provides foundation data and computational methods to enable further evaluation and optimisation of semi-recumbent cycling for application in rehabilitation after SCI and other neurological disorders.
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Affiliation(s)
- Claire B Crossley
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; School of Health Sciences and Social Work, Griffith University, Australia
| | - Laura E Diamond
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; School of Health Sciences and Social Work, Griffith University, Australia
| | - David J Saxby
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; School of Health Sciences and Social Work, Griffith University, Australia
| | - Ana de Sousa
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; Research Centre for Biomedical Engineering (CREB) at the Universitat Politècnica de Catalunya (UPC), Barcelona, Spain
| | - David G Lloyd
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; School of Health Sciences and Social Work, Griffith University, Australia
| | - Che Fornusek
- Exercise & Sports Science, Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Australia
| | - Claudio Pizzolato
- Griffith Centre of Biomedical and Rehabilitation Engineering (GCORE), Griffith University, Australia; School of Health Sciences and Social Work, Griffith University, Australia.
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Petrie MA, Kimball AL, Shields RK. Acute Low Force Electrically Induced Exercise Modulates Post Prandial Glycemic Markers in People with Spinal Cord Injury. J Funct Morphol Kinesiol 2022; 7:jfmk7040089. [PMID: 36278750 PMCID: PMC9624321 DOI: 10.3390/jfmk7040089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 11/29/2022] Open
Abstract
Regular exercise involves daily muscle contractions helping metabolize up to 70% of daily ingested glucose. Skeletal muscle increases glucose uptake through two distinct pathways: insulin signaling pathway and muscle contraction mediated AMPK pathway. People with paralysis are unable to contract their muscles which atrophy, transform into insulin resistant glycolytic muscle, and develop osteoporosis. Our goal is to determine if low force electrically induced exercise (LFE) will modulate the post prandial insulin and glucose response in people with and without spinal cord injury (SCI). 18 people with SCI and 23 without SCI (Non-SCI) participated in an assessment of metabolic biomarkers during passive sitting (CTL) and a bout of LFE delivered to the quadriceps/hamstring muscle groups after a glucose challenge. Baseline fasting insulin (p = 0.003) and lactate (p = 0.033) levels were higher in people with SCI, but glucose levels (p = 0.888) were similar compared to the non-SCI population. After 1-h of muscle contractions using LFE, heart rate increased (p < 0.001), capillary glucose decreased (p = 0.004), insulin decreased (p < 0.001), and lactate increased (p = 0.001) in the SCI population. These findings support that LFE attenuates certain metabolic blood biomarkers during a glucose challenge and may offer a lifestyle strategy to regulate metabolic responses after eating among people with SCI.
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Ghatas MP, Sutor TW, Gorgey AS. Prediction of Distal Femur and Proximal Tibia Bone Mineral Density From Total Body Dual Energy X-Ray Absorptiometry Scans in Persons with Spinal Cord Injury. J Clin Densitom 2022; 25:252-260. [PMID: 34920939 DOI: 10.1016/j.jocd.2021.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 10/01/2021] [Accepted: 11/08/2021] [Indexed: 11/30/2022]
Abstract
Bone density decreases rapidly after spinal cord injury (SCI), increasing fracture risk. The most common fracture sites are at the knee (i.e., distal femur or proximal tibia). Despite this high fracture incidence, knee-specific scans for bone density using dual x-ray absorptiometry (DXA) were not available until 2014 and are still not routinely used in clinical practice today. This has made it difficult to determine the rehabilitation efficacy and hindered understanding of the long-term changes in knee areal bone density. The purpose of this investigation was to compare areal bone mineral density values for the knee from both total-body and knee-specific DXA scans in persons with SCI. A total of 20 participants (16 males) >1 yr-post spinal cord injury received two DXA scans; a total-body scan and a knee-specific scan. Standardized methods were used to create regions of interest to determine bone density of four regions - the epiphysis and metaphysis of the distal femur and proximal tibia - from the total-body scan. Linear regressions and Bland-Altman analyses were conducted to determine the correlation (r2) and agreement (mean bias ± 95% level of agreement) respectively between the two scan types for each region. Linear regression analyses showed strong significant (p < 0.001) relationships between the two scan types for the distal femur epiphysis (r2 = 0.88) and metaphysis (r2 = 0.98) and the proximal tibia epiphysis (r2 = 0.88) and metaphysis (r2 = 0.99). The mean bias ± 95% level of agreement were distal femur epiphysis (0.05 ± 0.1 g/cm2) and metaphysis (0.02 ± 0.04 g/cm2); proximal tibia epiphysis (-0.02 ± 0.1 g/cm2) and metaphysis (0.02 ± 0.03 g/cm2). Results suggest knee-specific bone density can be assessed using a total-body DXA scan. This may allow for more comprehensive use of DXA scans which would reduce the burden of multiple site-specific scans for persons with SCI and enable more widespread adoption of knee bone density assessment in this population.
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Affiliation(s)
- Mina P Ghatas
- Spinal Cord Injury and Disorders Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA
| | - Tommy W Sutor
- Spinal Cord Injury and Disorders Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA
| | - Ashraf S Gorgey
- Spinal Cord Injury and Disorders Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA; Physical Medicine and Rehabilitation Virginia Commonwealth University, Richmond, VA, USA.
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Edwards WB, Haider IT, Simonian N, Barroso J, Schnitzer TJ. Durability and delayed treatment effects of zoledronic acid on bone loss after spinal cord injury: a randomized, controlled trial. J Bone Miner Res 2021; 36:2127-2138. [PMID: 34278611 DOI: 10.1002/jbmr.4416] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 12/28/2022]
Abstract
A single infusion of zoledronic acid (ZOL) after acute spinal cord injury (SCI) attenuates bone loss at the hip (proximal femur) and knee (distal femur and proximal tibia) for at least 6 months. The objective of this study was to examine the effects of timing and frequency of ZOL over 2 years. In this double-blind, placebo-controlled trial, we randomized 60 individuals with acute SCI (<120 days of injury) to receive either ZOL 5-mg infusion (n = 30) or placebo (n = 30). After 12 months, groups were again randomized to receive ZOL or placebo, resulting in four treatment groups for year 2: (i) ZOL both years; (ii) ZOL year 1, placebo year 2; (iii) placebo year 1, ZOL year 2; and (iv) placebo both years. Our primary outcome was bone loss at 12 months; compared to placebo, a single infusion of ZOL attenuated bone loss at the proximal femur, where median changes relative to baseline were -1.7% to -2.2% for ZOL versus -11.3% to -12.8% for placebo (p < 0.001). Similarly, the distal femur and proximal tibia showed changes of -4.7% to -9.6% for ZOL versus -8.9% to -23.0% for placebo (p ≤ 0.042). After 24 months, differences were significant at the proximal femur only (-3.2% to -6.0% for ZOL vs. -16.8% to -21.8% for placebo; p ≤ 0.018). Although not statistically significant, median bone density losses suggested some benefit from two annual infusions compared to a single baseline infusion, as well as from a single infusion 12 months after baseline compared to 2 years of placebo; therefore, further investigation in the 12-month to 24-month treatment window is warranted. No unanticipated adverse events associated with drug treatment were observed. In summary, ZOL 5-mg infusion after acute SCI was well-tolerated and may provide an effective therapeutic approach to prevent bone loss in the first few years following SCI. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- W Brent Edwards
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ifaz T Haider
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Narina Simonian
- Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.,Northwestern University Clinical and Translational Sciences Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Joana Barroso
- Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Thomas J Schnitzer
- Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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Petrie MA, Taylor EB, Suneja M, Shields RK. Genomic and Epigenomic Evaluation of Electrically Induced Exercise in People With Spinal Cord Injury: Application to Precision Rehabilitation. Phys Ther 2021; 102:6413907. [PMID: 34718779 PMCID: PMC8754383 DOI: 10.1093/ptj/pzab243] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/06/2021] [Accepted: 09/23/2021] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Physical therapists develop patient-centered exercise prescriptions to help overcome the physical, emotional, psychosocial, and environmental stressors that undermine a person's health. Optimally prescribing muscle activity for people with disability, such as a spinal cord injury, is challenging because of their loss of volitional movement control and the deterioration of their underlying skeletal systems. This report summarizes spinal cord injury-specific factors that should be considered in patient-centered, precision prescription of muscle activity for people with spinal cord injury. This report also presents a muscle genomic and epigenomic analysis to examine the regulation of the proliferator-activated receptor γ coactivator 1α (PGC-1α) (oxidative) and myostatin (hypertrophy) signaling pathways in skeletal muscle during low-frequency (lower-force) electrically induced exercise versus higher-frequency (higher-force) electrically induced exercise under constant muscle recruitment (intensity). METHODS Seventeen people with spinal cord injury participated in 1 or more unilateral electrically induced exercise sessions using a lower-force (1-, 3-, or 5-Hz) or higher-force (20-Hz) protocol. Three hours after the exercise session, percutaneous muscle biopsies were performed on exercised and nonexercised muscles for genomic and epigenomic analysis. RESULTS We found that low-frequency (low-force) electrically induced exercise significantly increased the expression of PGC-1α and decreased the expression of myostatin, consistent with the expression changes observed with high-frequency (higher-force) electrically induced exercise. Further, we found that low-frequency (lower-force) electrically induced exercise significantly demethylated, or epigenetically promoted, the PGC-1α signaling pathway. A global epigenetic analysis showed that >70 pathways were regulated with low-frequency (lower-force) electrically induced exercise. CONCLUSION These novel results support the notion that low-frequency (low-force) electrically induced exercise may offer a more precise rehabilitation strategy for people with chronic paralysis and severe osteoporosis. Future clinical trials are warranted to explore whether low-frequency (lower-force) electrically induced exercise training affects the overall health of people with chronic spinal cord injury.
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Affiliation(s)
- Michael A Petrie
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Eric B Taylor
- Department of Biochemistry, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Manish Suneja
- Department of Internal Medicine, Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
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McMillan DW, Astorino TA, Correa MA, Nash MS, Gater DR. Virtual Strategies for the Broad Delivery of High Intensity Exercise in Persons With Spinal Cord Injury: Ongoing Studies and Considerations for Implementation. Front Sports Act Living 2021; 3:703816. [PMID: 34423292 PMCID: PMC8377288 DOI: 10.3389/fspor.2021.703816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/08/2021] [Indexed: 11/13/2022] Open
Abstract
Spinal cord injury (SCI) results in a multitude of metabolic co-morbidities that can be managed by exercise. As in the non-injured population, manipulation of exercise intensity likely allows for fruitful optimization of exercise interventions targeting metabolic health in persons with SCI. In this population, interventions employing circuit resistance training (CRT) exhibit significant improvements in outcomes including cardiorespiratory fitness, muscular strength, and blood lipids, and recent exploration of high intensity interval training (HIIT) suggests the potential of this strategy to enhance health and fitness. However, the neurological consequences of SCI result in safety considerations and constrain exercise approaches, resulting in the need for specialized exercise practitioners. Furthermore, transportation challenges, inaccessibility of exercise facilities, and other barriers limit the translation of high intensity "real world" exercise strategies. Delivering exercise via online ("virtual") platforms overcomes certain access barriers while allowing for broad distribution of high intensity exercise despite the limited number of population-specific exercise specialists. In this review, we initially discuss the need for "real world" high intensity exercise strategies in persons with SCI. We then consider the advantages and logistics of using virtual platforms to broadly deliver high intensity exercise in this population. Safety and risk mitigation are considered first followed by identifying strategies and technologies for delivery and monitoring of virtual high intensity exercise. Throughout the review, we discuss approaches from previous and ongoing trials and conclude by giving considerations for future efforts in this area.
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Affiliation(s)
- David W. McMillan
- Christine E. Lynn Rehabilitation Center for the Miami Project to Cure Paralysis, UHealth/Jackson Memorial, Miami, FL, United States
- Department of Physical Medicine & Rehabilitation, University of Miami Leonard M. Miller School of Medicine, Miami, FL, United States
| | - Todd A. Astorino
- Department of Kinesiology, California State University San Marcos, San Marcos, CA, United States
| | - Michael A. Correa
- Christine E. Lynn Rehabilitation Center for the Miami Project to Cure Paralysis, UHealth/Jackson Memorial, Miami, FL, United States
| | - Mark S. Nash
- Christine E. Lynn Rehabilitation Center for the Miami Project to Cure Paralysis, UHealth/Jackson Memorial, Miami, FL, United States
- Department of Physical Medicine & Rehabilitation, University of Miami Leonard M. Miller School of Medicine, Miami, FL, United States
- Department of Neurological Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, FL, United States
| | - David R. Gater
- Christine E. Lynn Rehabilitation Center for the Miami Project to Cure Paralysis, UHealth/Jackson Memorial, Miami, FL, United States
- Department of Physical Medicine & Rehabilitation, University of Miami Leonard M. Miller School of Medicine, Miami, FL, United States
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Schmoll M, Le Guillou R, Lobato Borges D, Fattal C, Fachin-Martins E, Azevedo Coste C. Standardizing fatigue-resistance testing during electrical stimulation of paralysed human quadriceps muscles, a practical approach. J Neuroeng Rehabil 2021; 18:11. [PMID: 33478556 PMCID: PMC7818559 DOI: 10.1186/s12984-021-00805-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/11/2021] [Indexed: 11/10/2022] Open
Abstract
Background Rapid onset of muscular fatigue is still one of the main issues of functional electrical stimulation (FES). A promising technique, known as distributed stimulation, aims to activate sub-units of a muscle at a lower stimulation frequency to increase fatigue-resistance. Besides a general agreement on the beneficial effects, the great heterogeneity of evaluation techniques, raises the demand for a standardized method to better reflect the requirements of a practical application. Methods This study investigated the fatigue-development of 6 paralysed quadriceps muscles over the course of 180 dynamic contractions, evaluating different electrode-configurations (conventional and distributed stimulation). For a standardized comparison, fatigue-testing was performed at 40% of the peak-torque during a maximal evoked contraction (MEC). Further, we assessed the isometric torque for each electrode-configuration at different knee-extension-angles (70°–170°, 10° steps). Results Our results showed no significant difference in the fatigue-index for any of the tested electrode-configurations, compared to conventional-stimulation. We conjecture that the positive effects of distributed stimulation become less pronounced at higher stimulation amplitudes. The isometric torque produced at different knee-extension angles was similar for most electrode-configurations. Maximal torque-production was found at 130°–140° knee-extension-angle, which correlates with the maximal knee-flexion-angles during running. Conclusion In most practical applications, FES is intended to initiate dynamic movements. Therefore, it is crucial to assess fatigue-resistance by using dynamic contractions. Reporting the relationship between produced torque and knee-extension-angle can help to observe the stability of a chosen electrode-configuration for a targeted range-of-motion. Additionally, we suggest to perform fatigue testing at higher forces (e.g. 40% of the maximal evoked torque) in pre-trained subjects with SCI to better reflect the practical demands of FES-applications.
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Affiliation(s)
- Martin Schmoll
- INRIA - LIRMM, Université de Montpellier, Montpellier, France.
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Donovan J, Snider B, Miller A, Kirshblum S. Walking after Spinal Cord Injury: Current Clinical Approaches and Future Directions. CURRENT PHYSICAL MEDICINE AND REHABILITATION REPORTS 2020. [DOI: 10.1007/s40141-020-00277-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Thakkar P, Prakash NB, Tharion G, Shetty S, Paul TV, Bondu J, Yadav B. Evaluating Bone Loss with Bone Turnover Markers Following Acute Spinal Cord Injury. Asian Spine J 2019; 14:97-105. [PMID: 31679327 PMCID: PMC7010505 DOI: 10.31616/asj.2019.0004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 05/20/2019] [Indexed: 01/23/2023] Open
Abstract
STUDY DESIGN Prospective observational study. PURPOSE To evaluate bone turnover markers (BTMs) in individuals with acute spinal cord injury (SCI) and to compare the results with those of healthy controls and postmenopausal females. OVERVIEW OF LITERATURE SCI significantly impacts bone health. Change in bone mineral density appears 6 months after SCI and rapid bone loss during the acute phase is often underestimated, resulting in osteoporosis and a high risk of sublesional fractures. However, few studies have evaluated BTMs in the Indian SCI population. Despite a high risk of fracture, there are no guidelines for the diagnosis, monitoring, and management of SCI-induced osteoporosis. METHODS Twenty patients within 1 month of traumatic SCI who had been admitted to a tertiary care rehabilitation center were included in this study. Serum BTMs, C telopeptide (CTX) as a bone resorption marker, and osteocalcin as a bone formation marker, were serially measured at baseline, and 3 and 6 months after SCI. BTMs of SCI patients were compared with those of a control group of age-matched healthy males, premenopausal females, and a vulnerable group of postmenopausal females. RESULTS BTMs were significantly elevated in patients with SCI, with maximum levels observed at the 3rd month of injury. At baseline, the bone resorption marker CTX was approximately 3 times higher in SCI patients than in the control male population and premenopausal females, and about double that of postmenopausal females. The rise in the bone formation marker was marginal in comparison to that of the bone resorption marker. BTMs were persistently elevated and did not reach the normative range until the 6th month of SCI. CONCLUSIONS Raised bone resorption markers in comparison to bone formation markers indicate hyper-resorption-related bone loss following acute SCI. Markedly elevated bone resorption markers in the SCI population, compared with those in control and vulnerable groups, emphasize the need for early bone health monitoring and management.
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Affiliation(s)
- Prince Thakkar
- Department of Physical Medicine and Rehabilitation, Christian Medical College, Vellore, India
| | - Naveen B Prakash
- Department of Physical Medicine and Rehabilitation, Christian Medical College, Vellore, India
| | - George Tharion
- Department of Physical Medicine and Rehabilitation, Christian Medical College, Vellore, India
| | - Sahana Shetty
- Department of Endocrinology, Christian Medical College, Vellore, India
| | - Thomas V Paul
- Department of Endocrinology, Christian Medical College, Vellore, India
| | - Joseph Bondu
- Department of Clinical Biochemistry, Christian Medical College, Vellore, India
| | - Bijesh Yadav
- Department of Biostatistics, Christian Medical College, Vellore, India
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Zleik N, Weaver F, Harmon RL, Le B, Radhakrishnan R, Jirau-Rosaly WD, Craven BC, Raiford M, Hill JN, Etingen B, Guihan M, Heggeness MH, Ray C, Carbone L. Prevention and management of osteoporosis and osteoporotic fractures in persons with a spinal cord injury or disorder: A systematic scoping review. J Spinal Cord Med 2019; 42:735-759. [PMID: 29745791 PMCID: PMC6830234 DOI: 10.1080/10790268.2018.1469808] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Objectives: The primary objective was to review the literature regarding methodologies to assess fracture risk, to prevent and treat osteoporosis and to manage osteoporotic fractures in SCI/D.Study Design: Scoping review.Settings/Participants: Human adult subjects with a SCI/D.Outcome measures: Strategies to identify persons with SCI/D at risk for osteoporotic fractures, nonpharmacological and pharmacological therapies for osteoporosis and management of appendicular fractures.Results: 226 articles were included in the scoping review. Risk of osteoporotic fractures in SCI is predicted by a combination of DXA-defined low BMD plus clinical and demographic characteristics. Screening for secondary causes of osteoporosis, in particular hyperparathyroidism, hyperthyroidism, vitamin D insufficiency and hypogonadism, should be considered. Current antiresorptive therapies for treatment of osteoporosis have limited efficacy. Use of surgery to treat fractures has increased and outcomes are good and comparable to conservative treatment in most cases. A common adverse event following fracture was delayed healing.Conclusions: Most of the research in this area is limited by small sample sizes, weak study designs, and significant variation in populations studied. Future research needs to address cohort definition and study design issues.
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Affiliation(s)
- Nour Zleik
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia, USA
- Department of Medicine, Division of Rheumatology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Frances Weaver
- Center of Innovation for Complex Chronic Healthcare (CINCCH), Health Services Research & Development, Department of Veterans Affairs, Hines VA Hospital, Hines, Illinois, USA
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University, Maywood, Illinois, USA
| | - Robert L. Harmon
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia, USA
| | - Brian Le
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia, USA
- Department of Medicine, Division of Rheumatology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | | | - Wanda D. Jirau-Rosaly
- Department of Medicine, Division of Geriatrics, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - B. Catharine Craven
- Department of Medicine, Division of Physical Medicine and Rehabilitation, University of Toronto, Toronto, Ontario, Canada
| | - Mattie Raiford
- School of Medicine, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
| | - Jennifer N. Hill
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University, Maywood, Illinois, USA
| | - Bella Etingen
- Center of Innovation for Complex Chronic Healthcare (CINCCH), Health Services Research & Development, Department of Veterans Affairs, Hines VA Hospital, Hines, Illinois, USA
| | - Marylou Guihan
- Center of Innovation for Complex Chronic Healthcare (CINCCH), Health Services Research & Development, Department of Veterans Affairs, Hines VA Hospital, Hines, Illinois, USA
| | - Michael H. Heggeness
- Department of Orthopaedic Surgery, University of Kansas School of Medicine, Wichita, Kansas, USA
| | - Cara Ray
- Center of Innovation for Complex Chronic Healthcare (CINCCH), Health Services Research & Development, Department of Veterans Affairs, Hines VA Hospital, Hines, Illinois, USA
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University, Maywood, Illinois, USA
| | - Laura Carbone
- Charlie Norwood Veterans Administration Medical Center, Augusta, Georgia, USA
- Department of Medicine, Division of Rheumatology, Medical College of Georgia at Augusta University, Augusta, Georgia, USA
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Rinaldin CDP, Cabral LPA, Krueger E, Nogueira-Neto GN, Nohama P, Scheeren EM. Fatigue in complete spinal cord injury and implications on total delay. Artif Organs 2019; 44:305-313. [PMID: 31553061 DOI: 10.1111/aor.13573] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/11/2022]
Abstract
The use of neuromuscular electrical stimulation (NMES) to artificially restore movement in people with complete spinal cord injury (SCI) induces an accelerated process of muscle fatigue. Fatigue increases the time between the beginning of NMES and the onset of muscle force (DelayTOT ). Understanding how much muscle fatigue affects the DelayTOT in people with SCI could help in the design of closed-loop neuroprostheses that compensate for this delay, thus making the control system more stable. The aim of this study was to evaluate the impact of the extent of fatigue on DelayTOT and peak force of the lower limbs in people with complete SCI. Fifteen men-young adults with complete SCI (paraplegia and tetraplegia) and stable health-participated in the experiment. DelayTOT was defined as the time interval between the beginning of NMES application until the onset of muscle force. The electrical intensity of NMES applied was adjusted individually and consisted of the amplitude required to obtain a full extension of the knee (0°), considering the maximum electrically stimulated extension (MESE). Subsequently, 70% of the MESE was applied during the fatigue induction protocol. Significant differences were identified between the moments before and after the fatigue protocol, both for peak force (P ≤ .026) and DelayTOT (P ≤ .001). The medians and interquartile range of the DelayTOT were higher in postfatigue (199.0 ms) when compared to the moment before fatigue (146.5 ms). The medians and interquartile range of the peak force were higher in unfatigued lower limbs (0.43 kgf) when compared to the moment postfatigue (0.27 kgf). The results support the hypothesis that muscle fatigue influences the increase in DelayTOT and decrease in force production in people with SCI. For future applications, the combined evaluation of the delay and force in SCI patients provides valuable feedback for NMES paradigms. The study will provide potentially critical muscle mechanical evidence for the investigation of the evolution of atrophy.
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Affiliation(s)
| | - Luciane Patrícia Adreani Cabral
- Human Motricity Laboratory/PPGTS, Pontifical Catholic University of Paraná (PUCPR), Curitiba, Brazil.,Regional University Hospital of Campos Gerais, Campus of Ponta Grossa State University, Ponta Grossa, Brazil
| | - Eddy Krueger
- Neural Engineering and Rehabilitation Laboratory, Master and Doctoral Program in Rehabilitation Sciences UEL-UNOPAR, Anatomy Department, State University of Londrina, Londrina, Brazil.,Rehabilitation Engineering Laboratory/CPGEI/PPGEB, Federal Technological University of Paraná (UTFPR), Curitiba, Brazil
| | - Guilherme N Nogueira-Neto
- Rehabilitation Engineering Laboratory/PPGTS, Pontifical Catholic University of Paraná (PUCPR), Curitiba, Brazil
| | - Percy Nohama
- Rehabilitation Engineering Laboratory/CPGEI/PPGEB, Federal Technological University of Paraná (UTFPR), Curitiba, Brazil.,Rehabilitation Engineering Laboratory/PPGTS, Pontifical Catholic University of Paraná (PUCPR), Curitiba, Brazil
| | - Eduardo M Scheeren
- Human Motricity Laboratory/PPGTS, Pontifical Catholic University of Paraná (PUCPR), Curitiba, Brazil
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13
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Morse LR, Biering-Soerensen F, Carbone LD, Cervinka T, Cirnigliaro CM, Johnston TE, Liu N, Troy KL, Weaver FM, Shuhart C, Craven BC. Bone Mineral Density Testing in Spinal Cord Injury: 2019 ISCD Official Position. J Clin Densitom 2019; 22:554-566. [PMID: 31501005 DOI: 10.1016/j.jocd.2019.07.012] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 07/29/2019] [Indexed: 02/06/2023]
Abstract
Spinal cord injury (SCI) causes rapid osteoporosis that is most severe below the level of injury. More than half of those with motor complete SCI will experience an osteoporotic fracture at some point following their injury, with most fractures occurring at the distal femur and proximal tibia. These fractures have devastating consequences, including delayed union or nonunion, cellulitis, skin breakdown, lower extremity amputation, and premature death. Maintaining skeletal integrity and preventing fractures is imperative following SCI to fully benefit from future advances in paralysis cure research and robotic-exoskeletons, brain computer interfaces and other evolving technologies. Clinical care has been previously limited by the lack of consensus derived guidelines or standards regarding dual-energy X-ray absorptiometry-based diagnosis of osteoporosis, fracture risk prediction, or monitoring response to therapies. The International Society of Clinical Densitometry convened a task force to establish Official Positions for bone density assessment by dual-energy X-ray absorptiometry in individuals with SCI of traumatic or nontraumatic etiology. This task force conducted a series of systematic reviews to guide the development of evidence-based position statements that were reviewed by an expert panel at the 2019 Position Development Conference in Kuala Lumpur, Malaysia. The resulting the International Society of Clinical Densitometry Official Positions are intended to inform clinical care and guide the diagnosis of osteoporosis as well as fracture risk management of osteoporosis following SCI.
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Affiliation(s)
- Leslie R Morse
- Department of Rehabilitation Medicine, University of Minnesota School of Medicine, Minneapolis, MN, USA.
| | - Fin Biering-Soerensen
- Clinic for Spinal Cord Injuries, Neuroscience Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Laura D Carbone
- Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA; Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Tomas Cervinka
- Department of Physiotherapy and Rehabilitation, Faculty of Health and Welfare, Satakunta University of Applied Sciences, Pori, Finland
| | - Christopher M Cirnigliaro
- Department of Veterans Affairs Rehabilitation Research & Development Service National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USA
| | - Therese E Johnston
- Department of Physical Therapy, Jefferson College of Rehabilitation Sciences, Thomas Jefferson University, Philadelphia, PA
| | - Nan Liu
- Department of Rehabilitation Medicine and Osteoporosis and Metabolic Bone Disease Center, Peking University Third Hospital, Beijing, China
| | - Karen L Troy
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Frances M Weaver
- Center of Innovation for Complex Chronic Healthcare (CINCCH), Health Services Research & Development, Department of Veterans Affairs, Hines VA Hospital, Hines, IL, USA; Department of Public Health Sciences, Stritch School of Medicine, Loyola University, Maywood, IL, USA
| | - Christopher Shuhart
- Swedish Bone Health and Osteoporosis Center, Swedish Medical Group, Seattle WA, USA
| | - Beverley C Craven
- Neural Engineering and Therapeutics Team, KITE Research Institute - University Health Network, Department of Medicine, University of Toronto, Toronto, Ontario Canada
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14
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Morse LR, Troy KL, Fang Y, Nguyen N, Battaglino R, Goldstein RF, Gupta R, Taylor JA. Combination Therapy With Zoledronic Acid and FES-Row Training Mitigates Bone Loss in Paralyzed Legs: Results of a Randomized Comparative Clinical Trial. JBMR Plus 2019; 3:e10167. [PMID: 31131346 PMCID: PMC6524678 DOI: 10.1002/jbm4.10167] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 12/02/2018] [Accepted: 12/11/2018] [Indexed: 12/11/2022] Open
Abstract
Spinal cord injury (SCI) results in rapid, severe osteoporosis and an increased risk of lower extremity fractures. Despite the medical complications associated with these fractures, there is no standard of care to prevent osteoporotic fractures following SCI. Functional electrical stimulation- (FES-) assisted rowing is a promising intervention to improve bone health in SCI because of its ability to generate a muscular contraction in conjunction with mechanical loading of the lower extremity long bones. Combination therapy consisting of FES-rowing plus zoledronic acid (ZA) may be a superior treatment via inhibition of bone resorption and stimulation of new bone formation. We studied participants enrolled in a randomized clinical trial comparing FES-rowing alone with FES-rowing plus ZA to improve bone health in SCI. Volumetric CT scans at the distal femur and proximal tibial metaphyses were performed. Bone geometric properties (cortical thickness index [CTI], cortical compressive strength index [CSI], buckling ratio [BR], bending strength index) and mineral (cortical bone volume [CBV], cortical bone mineral density, cortical bone mineral content) indices were determined. In models adjusting for baseline values, we found that the CBV (p = 0.05 to 0.006), the CTI (p = 0.009), and the BR (p = 0.001) at both the distal femoral and proximal tibial metaphyses were greater in the ZA plus rowing group compared with the rowing-only group. Similarly, there was a significant positive association between the total rowing work completed and the BR at the proximal tibia (p = 0.05). A subgroup analysis of the rowing-only arm showed that gains in the CSI at the tibial metaphysis varied in a dose-dependent fashion based on the total amount of exercise performed (p = 0.009). These findings demonstrate that the osteogenic response to FES-rowing is dose-dependent. Combination therapy with ZA and FES-row training has therapeutic potential to improve bone quality, and perhaps reduce fracture risk at the most common fracture site following SCI. © 2019 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Affiliation(s)
- L R Morse
- Rocky Mountain Regional Spinal Injury System Craig Rehabilitation Hospital Englewood CO USA.,Department of PMR University of Colorado School of Medicine Aurora CO USA
| | - K L Troy
- Department of Biomedical Engineering Worcester Polytechnic Institute Worcester MA USA
| | - Y Fang
- Department of Biomedical Engineering Worcester Polytechnic Institute Worcester MA USA
| | - N Nguyen
- Rocky Mountain Regional Spinal Injury System Craig Rehabilitation Hospital Englewood CO USA
| | - R Battaglino
- Department of PMR University of Colorado School of Medicine Aurora CO USA
| | - R F Goldstein
- Rocky Mountain Regional Spinal Injury System Craig Rehabilitation Hospital Englewood CO USA
| | - R Gupta
- Department of Radiology Massachusetts General Hospital Boston MA USA
| | - J A Taylor
- Spaulding Rehabilitation Hospital Boston MA USA.,Department of Physical Medicine and Rehabilitation Harvard Medical School Boston MA USA
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15
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Lobos S, Cooke A, Simonett G, Ho C, Boyd SK, Edwards WB. Assessment of Bone Mineral Density at the Distal Femur and the Proximal Tibia by Dual-Energy X-ray Absorptiometry in Individuals With Spinal Cord Injury: Precision of Protocol and Relation to Injury Duration. J Clin Densitom 2018; 21:338-346. [PMID: 28662973 DOI: 10.1016/j.jocd.2017.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/25/2017] [Accepted: 05/15/2017] [Indexed: 10/19/2022]
Abstract
Spinal cord injury (SCI) is characterized by marked bone loss at the knee, and there is a need for established dual-energy X-ray absorptiometry (DXA) protocols to examine bone mineral density (BMD) at this location to track therapeutic progress and to monitor fracture risk. The purpose of this study was to quantify the precision and reliability of a DXA protocol for BMD assessment at the distal femur and the proximal tibia in individuals with SCI. The protocol was subsequently used to investigate the relationship between BMD and duration of SCI. Nine individuals with complete SCI and 9 able-bodied controls underwent 3 repeat DXA scans in accordance with the short-term precision methodology recommended by the International Society of Clinical Densitometry. The DXA protocol demonstrated a high degree of precision with the root-mean-square standard deviation ranging from 0.004 to 0.052 g/cm2 and the root-mean-square coefficient of variation ranging from 0.6% to 4.4%, depending on the bone, the region of interest, and the rater. All measurements of intra- and inter-rater reliability were excellent with an intraclass correlation of ≥0.950. The relationship between the BMD and the duration of SCI was well described by a logarithmic trend (r2 = 0.68-0.92). Depending on the region of interest, the logarithmic trends would predict that, after 3 yr of SCI, BMD at the knee would be 43%-19% lower than that in the able-bodied reference group. We believe the DXA protocol has the level of precision and reliability required for short-term assessments of BMD at the distal femur and the proximal tibia in people with SCI. However, further work is required to determine the degree to which this protocol may be used to assess longitudinal changes in BMD after SCI to examine clinical interventions and to monitor fracture risk.
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Affiliation(s)
- Stacey Lobos
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - Anne Cooke
- McCaig Institute for Bone and Joint Health, University of Calgary, University of Calgary, Calgary, Canada
| | - Gillian Simonett
- Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada
| | - Chester Ho
- Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Steven K Boyd
- McCaig Institute for Bone and Joint Health, University of Calgary, University of Calgary, Calgary, Canada; Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - W Brent Edwards
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada; McCaig Institute for Bone and Joint Health, University of Calgary, University of Calgary, Calgary, Canada; Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada.
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16
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Willingham TB, McCully KK. In Vivo Assessment of Mitochondrial Dysfunction in Clinical Populations Using Near-Infrared Spectroscopy. Front Physiol 2017; 8:689. [PMID: 28959210 PMCID: PMC5603672 DOI: 10.3389/fphys.2017.00689] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 08/28/2017] [Indexed: 12/13/2022] Open
Abstract
The ability to sustain submaximal exercise is largely dependent on the oxidative capacity of mitochondria within skeletal muscle, and impairments in oxidative metabolism have been implicated in many neurologic and cardiovascular pathologies. Here we review studies which have demonstrated the utility of Near-infrared spectroscopy (NIRS) as a method of evaluating of skeletal muscle mitochondrial dysfunction in clinical human populations. NIRS has been previously used to noninvasively measure tissue oxygen saturation, but recent studies have demonstrated the utility of NIRS as a method of evaluating skeletal muscle oxidative capacity using post-exercise recovery kinetics of oxygen metabolism. In comparison to historical methods of measuring muscle metabolic dysfunction in vivo, NIRS provides a more versatile and economical method of evaluating mitochondrial oxidative capacity in humans. These advantages generate great potential for the clinical applicability of NIRS as a means of evaluating muscle dysfunction in clinical populations.
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Affiliation(s)
| | - Kevin K McCully
- Department of Kinesiology, University of GeorgiaAthens, GA, United States
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17
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Woelfel JR, Kimball AL, Yen CL, Shields RK. Low-Force Muscle Activity Regulates Energy Expenditure after Spinal Cord Injury. Med Sci Sports Exerc 2017; 49:870-878. [PMID: 28009786 DOI: 10.1249/mss.0000000000001187] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Reduced physical activity is a primary risk factor for increased morbidity and mortality. People with spinal cord injury (SCI) have reduced activity for a lifetime, as they cannot volitionally activate affected skeletal muscles. We explored whether low-force and low-frequency stimulation is a viable strategy to enhance systemic energy expenditure in people with SCI. PURPOSE This study aimed to determine the effects of low stimulation frequency (1 and 3 Hz) and stimulation intensity (50 and 100 mA) on energy expenditure in people with SCI. We also examined the relationship between body mass index and visceral adipose tissue on energy expenditure during low-frequency stimulation. METHODS Ten individuals with complete SCI underwent oxygen consumption monitoring during electrical activation of the quadriceps and hamstrings at 1 and 3 Hz and at 50 and 100 mA. We calculated the difference in energy expenditure between stimulation and rest and estimated the number of days that would be necessary to burn 1 lb of body fat (3500 kcal) for each stimulation protocol (1 vs 3 Hz). RESULTS Both training frequencies induced a significant increase in oxygen consumption above a resting baseline level (P < 0.05). Energy expenditure positively correlated with stimulus intensity (muscle recruitment) and negatively correlated with adiposity (reflecting the insulating properties of adipose tissue). We estimated that 1 lb of body fat could be burned more quickly with 1 Hz training (58 d) as compared with 3 Hz training (87 d) if an identical number of pulses were delivered. CONCLUSION Low-frequency stimulation increased energy expenditure per pulse and may be a feasible option to subsidize physical activity to improve metabolic status after SCI.
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Affiliation(s)
- Jessica R Woelfel
- 1Carver College of Medicine, University of Iowa, Iowa City, IA; and 2Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, IA
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18
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Fang Y, Morse LR, Nguyen N, Tsantes NG, Troy KL. Anthropometric and biomechanical characteristics of body segments in persons with spinal cord injury. J Biomech 2017; 55:11-17. [PMID: 28284666 PMCID: PMC5430500 DOI: 10.1016/j.jbiomech.2017.01.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 11/18/2016] [Accepted: 01/24/2017] [Indexed: 11/22/2022]
Abstract
People with spinal cord injury (SCI) experience bone and muscle loss in their paralyzed limbs that is most rapid and severe in the first 3years after injury. Restoration of mechanical loading through therapeutic physical activity may potentially slow or reverse post-SCI bone loss, however, therapeutic targets cannot be developed without accurate biomechanical models. Obesity is prevalent among SCI population, and it alters body composition and further affects parameters of these models. Here, clinical whole body dual-energy X-ray absorptiometry data from people with acute (n=39) and chronic (n=61) SCI were analyzed to obtain anthropometric parameters including segment masses, center of mass location, and radius of gyration for both obese and non-obese individuals. Chronic SCI was associated with higher normalized trunk mass of 3.2%BW and smaller normalized leg mass of 1.8%BW in males, but no significant changes in segment centers of mass or radius of gyration. People with chronic SCI had 58.6% lean mass in the trunk, compared to 66.6% lean mass in those with acute SCI (p=0.01), with significant changes in all segments. Obesity was associated with an increase in trunk mass proportion of 3.1%BW, proximal shifts in thigh and upper arm center of mass, and changes to thigh and shank radius of gyration. The data presented here can be used to accurately represent the anthropometrics of SCI population in biomechanical studies, considering obesity and injury duration.
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Affiliation(s)
- Y Fang
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - L R Morse
- Rocky Mountain Regional Spinal Injury System, Craig Rehabilitation Hospital, Englewood, CO, USA; Department of PMR, University of Colorado School of Medicine, Aurora, CO, USA
| | - N Nguyen
- Spaulding Rehabilitation Hospital, Boston, MA, USA
| | - N G Tsantes
- Spaulding Rehabilitation Hospital, Boston, MA, USA
| | - K L Troy
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA.
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19
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Ibitoye MO, Hamzaid NA, Hasnan N, Abdul Wahab AK, Islam MA, Kean VSP, Davis GM. Torque and mechanomyogram relationships during electrically-evoked isometric quadriceps contractions in persons with spinal cord injury. Med Eng Phys 2016; 38:767-75. [PMID: 27289541 DOI: 10.1016/j.medengphy.2016.05.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 05/04/2016] [Accepted: 05/20/2016] [Indexed: 11/30/2022]
Abstract
The interaction between muscle contractions and joint loading produces torques necessary for movements during activities of daily living. However, during neuromuscular electrical stimulation (NMES)-evoked contractions in persons with spinal cord injury (SCI), a simple and reliable proxy of torque at the muscle level has been minimally investigated. Thus, the purpose of this study was to investigate the relationships between muscle mechanomyographic (MMG) characteristics and NMES-evoked isometric quadriceps torques in persons with motor complete SCI. Six SCI participants with lesion levels below C4 [(mean (SD) age, 39.2 (7.9) year; stature, 1.71 (0.05) m; and body mass, 69.3 (12.9) kg)] performed randomly ordered NMES-evoked isometric leg muscle contractions at 30°, 60° and 90° knee flexion angles on an isokinetic dynamometer. MMG signals were detected by an accelerometer-based vibromyographic sensor placed over the belly of rectus femoris muscle. The relationship between MMG root mean square (MMG-RMS) and NMES-evoked torque revealed a very high association (R(2)=0.91 at 30°; R(2)=0.98 at 60°; and R(2)=0.97 at 90° knee angles; P<0.001). MMG peak-to-peak (MMG-PTP) and stimulation intensity were less well related (R(2)=0.63 at 30°; R(2)=0.67 at 60°; and R(2)=0.45 at 90° knee angles), although were still significantly associated (P≤0.006). Test-retest interclass correlation coefficients (ICC) for the dependent variables ranged from 0.82 to 0.97 for NMES-evoked torque, between 0.65 and 0.79 for MMG-RMS, and from 0.67 to 0.73 for MMG-PTP. Their standard error of measurements (SEM) ranged between 10.1% and 31.6% (of mean values) for torque, MMG-RMS and MMG-PTP. The MMG peak frequency (MMG-PF) of 30Hz approximated the stimulation frequency, indicating NMES-evoked motor unit firing rate. The results demonstrated knee angle differences in the MMG-RMS versus NMES-isometric torque relationship, but a similar torque related pattern for MMG-PF. These findings suggested that MMG was well associated with torque production, reliably tracking the motor unit recruitment pattern during NMES-evoked muscle contractions. The strong positive relationship between MMG signal and NMES-evoked torque production suggested that the MMG might be deployed as a direct proxy for muscle torque or fatigue measurement during leg exercise and functional movements in the SCI population.
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Affiliation(s)
- Morufu Olusola Ibitoye
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biomedical Engineering, Faculty of Engineering and Technology, University of Ilorin, P. M. B. 1515 Ilorin, Nigeria
| | - Nur Azah Hamzaid
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Nazirah Hasnan
- Department of Rehabilitation Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Ahmad Khairi Abdul Wahab
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Md Anamul Islam
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Victor S P Kean
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Glen M Davis
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia; Clinical Exercise and Rehabilitation Unit, Discipline of Exercise and Sports Sciences, Faculty of Health Sciences, The University of Sydney, Sydney, 2006 NSW, Australia
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20
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Dudley-Javoroski S, Petrie MA, McHenry CL, Amelon RE, Saha PK, Shields RK. Bone architecture adaptations after spinal cord injury: impact of long-term vibration of a constrained lower limb. Osteoporos Int 2016; 27:1149-1160. [PMID: 26395887 PMCID: PMC4767656 DOI: 10.1007/s00198-015-3326-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 09/15/2015] [Indexed: 11/30/2022]
Abstract
SUMMARY This study examined the effect of a controlled dose of vibration upon bone density and architecture in people with spinal cord injury (who eventually develop severe osteoporosis). Very sensitive computed tomography (CT) imaging revealed no effect of vibration after 12 months, but other doses of vibration may still be useful to test. INTRODUCTION The purposes of this report were to determine the effect of a controlled dose of vibratory mechanical input upon individual trabecular bone regions in people with chronic spinal cord injury (SCI) and to examine the longitudinal bone architecture changes in both the acute and chronic state of SCI. METHODS Participants with SCI received unilateral vibration of the constrained lower limb segment while sitting in a wheelchair (0.6g, 30 Hz, 20 min, three times weekly). The opposite limb served as a control. Bone mineral density (BMD) and trabecular micro-architecture were measured with high-resolution multi-detector CT. For comparison, one participant was studied from the acute (0.14 year) to the chronic state (2.7 years). RESULTS Twelve months of vibration training did not yield adaptations of BMD or trabecular micro-architecture for the distal tibia or the distal femur. BMD and trabecular network length continued to decline at several distal femur sub-regions, contrary to previous reports suggesting a "steady state" of bone in chronic SCI. In the participant followed from acute to chronic SCI, BMD and architecture decline varied systematically across different anatomical segments of the tibia and femur. CONCLUSIONS This study supports that vibration training, using this study's dose parameters, is not an effective anti-osteoporosis intervention for people with chronic SCI. Using a high-spatial-resolution CT methodology and segmental analysis, we illustrate novel longitudinal changes in bone that occur after spinal cord injury.
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Affiliation(s)
- S Dudley-Javoroski
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA, 52242, USA
| | - M A Petrie
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA, 52242, USA
| | - C L McHenry
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA, 52242, USA
| | - R E Amelon
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA, USA
| | - P K Saha
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA, USA
- Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - R K Shields
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA, 52242, USA.
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21
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Johnston TE, Marino RJ, Oleson CV, Schmidt-Read M, Modlesky CM. Cycling with Functional Electrical Stimulation Before and After a Distal Femur Fracture in a Man with Paraplegia. Top Spinal Cord Inj Rehabil 2015; 21:275-81. [PMID: 26689692 DOI: 10.1310/sci2104-275] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
CASE PRESENTATION A man with chronic paraplegia sustained a distal femur fracture following an unrelated fall while enrolled in a study examining musculoskeletal changes after 6 months of cycling with functional electrical stimulation (FES). After healing, he restarted and completed the study. MANAGEMENT AND OUTCOME Study measures included areal bone mineral density, trabecular bone microarchitecture, cortical bone macroarchitecture, serum bone formation/resorption markers, and muscle volume. The patient made small gains in bone- and muscle-related measures. Bone markers had not returned to baseline prior to restarting cycling, which may have impacted results. DISCUSSION This case shows that cycling with FES may be safely resumed after distal femur fracture.
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Affiliation(s)
- Therese E Johnston
- Department of Physical Therapy, Jefferson School of Health Professions, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Ralph J Marino
- Department of Rehabilitation Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Christina V Oleson
- Department of Rehabilitation Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
| | | | - Christopher M Modlesky
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
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Abstract
Spinal cord injury (SCI) is characterized by marked bone loss and an increased risk of fracture with high complication rate. Recent research based on advanced imaging analysis, including quantitative computed tomography (QCT) and patient-specific finite element (FE) modeling, has provided new and important insights into the magnitude and temporal pattern of bone loss, as well as the associated changes to bone structure and strength, following SCI. This work has illustrated the importance of early therapeutic treatment to prevent bone loss after SCI and may someday serve as the basis for a clinical fracture risk assessment tool for the SCI population. This review provides an update on the epidemiology of fracture after SCI and discusses new findings and significant developments related to bone loss and fracture risk assessment in the SCI population based on QCT analysis and patient-specific FE modeling.
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Affiliation(s)
- W Brent Edwards
- Human Performance Laboratory, Faculty of Kinesiology, and Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N 1N4, Canada,
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Edwards WB, Simonian N, Troy KL, Schnitzer TJ. Reduction in Torsional Stiffness and Strength at the Proximal Tibia as a Function of Time Since Spinal Cord Injury. J Bone Miner Res 2015; 30:1422-30. [PMID: 25656743 DOI: 10.1002/jbmr.2474] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 01/20/2015] [Accepted: 02/03/2015] [Indexed: 11/10/2022]
Abstract
Spinal cord injury (SCI) is characterized by marked bone loss and a high rate of low-energy fracture around regions of the knee. Changes in the mechanical integrity of bone after SCI are poorly defined, and a better understanding may inform approaches to prevent fractures. The purpose of this study was to quantify reductions in torsional stiffness and strength at the proximal tibia as a function of time since SCI. Sixty adults with SCI ranging from 0 to 50 years of duration and a reference group of 10 able-bodied controls received a CT scan of the proximal tibia. Measures of integral bone mineral were calculated for the total proximal tibia, and localized measures of cortical and trabecular bone mineral were calculated for the epiphysis, metaphysis, and diaphysis. Torsional stiffness (K) and strength (T(ult)) for the total proximal tibia were quantified using validated subject-specific finite element models. Total proximal tibia measures of integral bone mineral, K, and T(ult) decreased exponentially (r(2) = 0.52 to 0.70) and reached a new steady state within 2.1 to 2.7 years after SCI. Whereas new steady-state values for integral bone mineral and K were 52% to 56% (p < 0.001) lower than the reference group, the new steady state for T(ult) was 69% (p < 0.001) lower than the reference group. Reductions in total proximal tibia measures occurred through a combination of trabecular and endocortical resorption, leaving a bone comprised primarily of marrow fat rather than hydroxyapatite. These findings illustrate that a short therapeutic window exists early (ie, 2 years) after SCI, during which bone-specific intervention may attenuate reductions in mechanical integrity and ultimately prevent SCI-related fragility fracture.
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Affiliation(s)
- W Brent Edwards
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - Narina Simonian
- Department of Physical Medicine and Rehabilitation Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Karen L Troy
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Thomas J Schnitzer
- Department of Physical Medicine and Rehabilitation Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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Functional electrical stimulation: cardiorespiratory adaptations and applications for training in paraplegia. Sports Med 2015; 45:71-82. [PMID: 25205000 DOI: 10.1007/s40279-014-0250-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Regular exercise can be broadly beneficial to health and quality of life in humans with spinal cord injury (SCI). However, exercises must meet certain criteria, such as the intensity and muscle mass involved, to induce significant benefits. SCI patients can have difficulty achieving these exercise requirements since the paralysed muscles cannot contribute to overall oxygen consumption. One solution is functional electrical stimulation (FES) and, more importantly, hybrid training that combines volitional arm and electrically controlled contractions of the lower limb muscles. However, it might be rather complicated for therapists to use FES because of the wide variety of protocols that can be employed, such as stimulation parameters or movements induced. Moreover, although the short-term physiological and psychological responses during different types of FES exercises have been extensively reported, there are fewer data regarding the long-term effects of FES. Therefore, the purpose of this brief review is to provide a critical appraisal and synthesis of the literature on the use of FES for exercise in paraplegic individuals. After a short introduction underlying the importance of exercise for SCI patients, the main applications and effects of FES are reviewed and discussed. Major findings reveal an increased physiological demand during FES hybrid exercises as compared with arms only exercises. In addition, when repeated within a training period, FES exercises showed beneficial effects on muscle characteristics, force output, exercise capacity, bone mineral density and cardiovascular parameters. In conclusion, there appears to be promising evidence of beneficial effects of FES training, and particularly FES hybrid training, for paraplegic individuals.
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Petrie M, Suneja M, Shields RK. Low-frequency stimulation regulates metabolic gene expression in paralyzed muscle. J Appl Physiol (1985) 2015; 118:723-31. [PMID: 25635001 DOI: 10.1152/japplphysiol.00628.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The altered metabolic state after a spinal cord injury compromises systemic glucose regulation. Skeletal muscle atrophies and transforms into fast, glycolytic, and insulin-resistant tissue. Osteoporosis is common after spinal cord injury and limits the ability to exercise paralyzed muscle. We used a novel approach to study the acute effect of two frequencies of stimulation (20 and 5 Hz) on muscle fatigue and gene regulation in people with chronic paralysis. Twelve subjects with chronic (>1 yr) and motor complete spinal cord injury (ASIA A) participated in the study. We assessed the twitch force before and after a single session of electrical stimulation (5 or 20 Hz). We controlled the total number of pulses delivered for each protocol (10,000 pulses). Three hours after the completion of the electrical stimulation (5 or 20 Hz), we sampled the vastus lateralis muscle and examined genes involved with metabolic transcription, glycolysis, oxidative phosphorylation, and mitochondria remodeling. We discovered that the 5-Hz stimulation session induced a similar amount of fatigue and a five- to sixfold increase (P < 0.05) in key metabolic transcription factors, including PGC-1α, NR4A3, and ABRA as the 20-Hz session. Neither session showed a robust regulation of genes for glycolysis, oxidative phosphorylation, or mitochondria remodeling. We conclude that a low-force and low-frequency stimulation session is effective at inducing fatigue and regulating key metabolic transcription factors in human paralyzed muscle. This strategy may be an acceptable intervention to improve systemic metabolism in people with chronic paralysis.
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Affiliation(s)
- Michael Petrie
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Manish Suneja
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Richard K Shields
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; Department of Veterans Affairs, Veterans Affairs Medical Center, Iowa City, Iowa
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Gorgey AS, Dolbow DR, Dolbow JD, Khalil RK, Gater DR. The effects of electrical stimulation on body composition and metabolic profile after spinal cord injury--Part II. J Spinal Cord Med 2015; 38:23-37. [PMID: 25001669 PMCID: PMC4293531 DOI: 10.1179/2045772314y.0000000244] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Diet and exercise are cornerstones in the management of obesity and associated metabolic complications, including insulin resistance, type 2 diabetes, and disturbances in the lipid profile. However, the role of exercise in managing body composition adaptations and metabolic disorders after spinal cord injury (SCI) is not well established. The current review summarizes evidence about the efficacy of using neuromuscular electrical stimulation or functional electrical stimulation in exercising the paralytic lower extremities to improve body composition and metabolic profile after SCI. There are a number of trials that investigated the effects on muscle cross-sectional area, fat-free mass, and glucose/lipid metabolism. The duration of the intervention in these trials varied from 6 weeks to 24 months. Training frequency ranged from 2 to 5 days/week. Most studies documented significant increases in muscle size but no noticeable changes in adipose tissue. While increases in skeletal muscle size after twice weekly training were greater than those trials that used 3 or 5 days/week, other factors such as differences in the training mode, i.e. resistance versus cycling exercise and pattern of muscle activation may be responsible for this observation. Loading to evoke muscle hypertrophy is a key component in neuromuscular training after SCI. The overall effects on lean mass were modest and did not exceed 10% and the effects of training on trunk or pelvic muscles remain unestablished. Most studies reported improvement in glucose metabolism with the enhancement of insulin sensitivity being the major factor following training. The effect on lipid profile is unclear and warrants further investigation.
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Affiliation(s)
- Ashraf S. Gorgey
- Correspondence to: Ashraf S. Gorgey, Department of Veterans Affairs, Hunter Holmes McGuire Medical Center, Spinal Cord Injury & Disorders Service, 1201 Broad Rock Boulevard, Richmond, VA 23249, USA.
| | - David R. Dolbow
- School of Human Performance and Recreation, University of Southern Mississippi, Hattiesburg, MS, USA
| | - James D. Dolbow
- Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA
| | - Refka K. Khalil
- Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA
| | - David R. Gater
- Department of Physical Medicine and Rehabilitation, Penn State University, Penn State College of Medicine, Hershey, PA, USA
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FES-rowing in tetraplegia: a preliminary report. Spinal Cord 2014; 52:880-6. [PMID: 25266698 DOI: 10.1038/sc.2014.159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 08/01/2014] [Accepted: 08/12/2014] [Indexed: 11/08/2022]
Abstract
STUDY DESIGN A training intervention study using functional electrical stimulation-rowing (FES-R) in a group of eight individuals with tetraplegia. OBJECTIVES To assess the feasibility of a structured progressive FES-R training programme in people with tetraplegia, and to explore the number and type of FES-training sessions required to enable continuous FES-R for 30 min. SETTING A fully integrated sports centre, elite rowing training centre and university sport science department. METHODS Eight participants with chronic complete and incomplete tetraplegia (C4 to C7, American Spinal Injury Association Impairment Scale A, B and C) who had not previously used any form of FES-assisted exercise, participated in the study. Participants completed a progressive FES-assisted training programme building to three continuous 30-min FES-R sessions per week at 60-80% of their predetermined peak power output. Thereafter, rowing performance was monitored for 12 months. MAIN OUTCOME MEASURES number and type of FES-training sessions required before achieving 30-min continuous FES-R, and FES-R average power output (POav) pre and post 12 months training. Participant feedback of perceived benefits was also documented. RESULTS All participants were able to continuously FES-row for 30 min after completing 13±7 FES-R training sessions. Each individual POav during 30 min FES-R increased over 12 months FES-training. FES-R was found safe and well tolerated in this group of individuals with tetraplegia. CONCLUSION Individuals with tetraplegia are able to engage in a progressive programme of FES-R training. Future research examining FES-R training as an adjunctive therapy in people with tetraplegia is warranted.
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Petrie MA, Suneja M, Faidley E, Shields RK. Low force contractions induce fatigue consistent with muscle mRNA expression in people with spinal cord injury. Physiol Rep 2014; 2:e00248. [PMID: 24744911 PMCID: PMC3966256 DOI: 10.1002/phy2.248] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 01/30/2014] [Accepted: 01/31/2014] [Indexed: 11/11/2022] Open
Abstract
Spinal cord injury (SCI) is associated with muscle atrophy, transformation of muscle fibers to a fast fatigable phenotype, metabolic inflexibility (diabetes), and neurogenic osteoporosis. Electrical stimulation of paralyzed muscle may mitigate muscle metabolic abnormalities after SCI, but there is a risk for a fracture to the osteoporotic skeletal system. The goal of this study was to determine if low force stimulation (3 Hz) causes fatigue of chronically paralyzed muscle consistent with selected muscle gene expression profiles. We tested 29 subjects, nine with a SCI and 20 without and SCI, during low force fatigue protocol. Three SCI and three non-SCI subjects were muscle biopsied for gene and protein expression analysis. The fatigue index (FI) was 0.21 ± 0.27 and 0.91 ± 0.01 for the SCI and non-SCI groups, respectively, supporting that the low force protocol physiologically fatigued the chronically paralyzed muscle. The post fatigue potentiation index (PI) for the SCI group was increased to 1.60 ± 0.06 (P <0.001), while the non-SCI group was 1.26 ± 0.02 supporting that calcium handling was compromised with the low force stimulation. The mRNA expression from genes that regulate atrophy and fast properties (MSTN, ANKRD1, MYH8, and MYCBP2) was up regulated, while genes that regulate oxidative and slow muscle properties (MYL3, SDHB, PDK2, and RyR1) were repressed in the chronic SCI muscle. MSTN, ANKRD1, MYH8, MYCBP2 gene expression was also repressed 3 h after the low force stimulation protocol. Taken together, these findings support that a low force single twitch activation protocol induces paralyzed muscle fatigue and subsequent gene regulation. These findings suggest that training with a low force protocol may elicit skeletal muscle adaptations in people with SCI.
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Affiliation(s)
- Michael A Petrie
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Manish Suneja
- Department of Internal Medicine, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Elizabeth Faidley
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Richard K Shields
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, Iowa ; Department of Veterans Affairs, VA Medical Center, Iowa City, Iowa
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Chilibeck PD, Vatanparast H, Cornish SM, Abeysekara S, Charlesworth S. Evidence-based risk assessment and recommendations for physical activity: arthritis, osteoporosis, and low back pain. Appl Physiol Nutr Metab 2013; 36 Suppl 1:S49-79. [PMID: 21800948 DOI: 10.1139/h11-037] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We systematically reviewed the safety of physical activity (PA) for people with arthritis, osteoporosis, and low back pain. We searched PubMed, MEDLINE, Sport Discus, and the Cochrane Central Register of Controlled Trials (1966 through March 2008) for relevant articles on PA and adverse events. A total of 111 articles met our inclusion criteria. The incidence for adverse events during PA was 3.4%-11% (0.06%-2.4% serious adverse events) and included increased joint pain, fracture, and back pain for those with arthritis, osteoporosis, and low back pain, respectively. Recommendations were based on the Appraisal of Guidelines for Research and Evaluation, which applies Levels of Evidence based on type of study ranging from high-quality randomized controlled trials (Level 1) to anecdotal evidence (Level 4) and Grades from A (strong) to C (weak). Our main recommendations are that (i) arthritic patients with highly progressed forms of disease should avoid heavy load-bearing activities, but should participate in non-weight-bearing activities (Level 2, Grade A); and (ii) patients with osteoporosis should avoid trunk flexion (Level 2, Grade A) and powerful twisting of the trunk (Level 3, Grade C); (iii) patients with acute low back pain can safely do preference-based PA (i.e., PA that does not induce pain), including low back extension and flexion (Level 2, Grade B); (iv) arthritic patients with stable disease without progressive joint damage and patients with stable osteoporosis or low back pain can safely perform a variety of progressive aerobic or resistance-training PAs (Level 2, Grades A and B). Overall, the adverse event incidence from reviewed studies was low. PA can safely be done by most individuals with musculoskeletal conditions.
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Affiliation(s)
- Philip D Chilibeck
- College of Kinesiology, University of Saskatchewan, 87 Campus Drive, Saskatoon, SK, Canada.
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Shields RK, Dudley-Javoroski S. Fatigue modulates synchronous but not asynchronous soleus activation during stimulation of paralyzed muscle. Clin Neurophysiol 2013; 124:1853-60. [PMID: 23673062 DOI: 10.1016/j.clinph.2013.03.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 03/07/2013] [Accepted: 03/15/2013] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Electrical stimulation over a motor nerve yields muscle force via a combination of direct and reflex-mediated activation. We determined the influence of fatigue on reflex-mediated responses induced during supra-maximal electrical stimulation in humans with complete paralysis. METHODS We analyzed soleus electromyographic (EMG) activity during repetitive stimulation (15 Hz, 125 contractions) in 22 individuals with complete paralysis. The bout of stimulation caused significant soleus muscle fatigue (53.1% torque decline). RESULTS Before fatigue, EMG at all latencies after the M-wave was less than 1% of the maximal M-wave amplitude (% MaxM). After fatigue there was a fourfold (p < 0.05) increase in EMG at the H-reflex latency; however, the overall magnitude remained low (< 2% change in % MaxM). There was no increase in "asynchronous" EMG ∼ 1 s after the stimulus train. CONCLUSIONS Fatigue enhanced the activation to the paralyzed soleus muscle, but primarily at the H-reflex latency. The overall influence of this reflex modulation was small. Soleus EMG was not elevated during fatigue at latencies consistent with asynchronous activation. SIGNIFICANCE These findings support synchronous reflex responses increase while random asynchronous reflex activation does not change during repetitive supra-maximal stimulation, offering a clinical strategy to consistently dose stress to paralyzed tissues.
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Affiliation(s)
- Richard K Shields
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA.
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Dudley-Javoroski S, Saha PK, Liang G, Li C, Gao Z, Shields RK. High dose compressive loads attenuate bone mineral loss in humans with spinal cord injury. Osteoporos Int 2012; 23:2335-46. [PMID: 22187008 PMCID: PMC3374128 DOI: 10.1007/s00198-011-1879-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 11/04/2011] [Indexed: 10/14/2022]
Abstract
UNLABELLED People with spinal cord injury (SCI) lose bone and muscle integrity after their injury. Early doses of stress, applied through electrically induced muscle contractions, preserved bone density at high-risk sites. Appropriately prescribed stress early after the injury may be an important consideration to prevent bone loss after SCI. INTRODUCTION Skeletal muscle force can deliver high compressive loads to bones of people with spinal cord injury (SCI). The effective osteogenic dose of load for the distal femur, a chief site of fracture, is unknown. The purpose of this study is to compare three doses of bone compressive loads at the distal femur in individuals with complete SCI who receive a novel stand training intervention. METHODS Seven participants performed unilateral quadriceps stimulation in supported stance [150% body weight (BW) compressive load-"High Dose" while opposite leg received 40% BW-"Low Dose"]. Five participants stood passively without applying quadriceps electrical stimulation to either leg (40% BW load-"Low Dose"). Fifteen participants performed no standing (0% BW load-"Untrained") and 14 individuals without SCI provided normative data. Participants underwent bone mineral density (BMD) assessment between one and six times over a 3-year training protocol. RESULTS BMD for the High Dose group significantly exceeded BMD for both the Low Dose and the Untrained groups (p < 0.05). No significant difference existed between the Low Dose and Untrained groups (p > 0.05), indicating that BMD for participants performing passive stance did not differ from individuals who performed no standing. High-resolution CT imaging of one High Dose participant revealed 86% higher BMD and 67% higher trabecular width in the High Dose limb. CONCLUSION Over 3 years of training, 150% BW compressive load in upright stance significantly attenuated BMD decline when compared to passive standing or to no standing. High-resolution CT indicated that trabecular architecture was preserved by the 150% BW dose of load.
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Affiliation(s)
- S. Dudley-Javoroski
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242-1190, USA
| | - P. K. Saha
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA 52242-1190, USA
- Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, IA 52242-1190, USA
| | - G. Liang
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA 52242-1190, USA
| | - C. Li
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA 52242-1190, USA
| | - Z. Gao
- Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, IA 52242-1190, USA
| | - R. K. Shields
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, 1-252 Medical Education Building, Iowa City, IA 52242-1190, USA
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Giangregorio L, Craven C, Richards K, Kapadia N, Hitzig SL, Masani K, Popovic MR. A randomized trial of functional electrical stimulation for walking in incomplete spinal cord injury: effects on body composition. J Spinal Cord Med 2012; 35:351-60. [PMID: 23031172 PMCID: PMC3459564 DOI: 10.1179/2045772312y.0000000041] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
OBJECTIVE To evaluate the effects of functional electrical stimulation (FES)-assisted walking on body composition, compared to a non-FES exercise program in individuals with a spinal cord injury (SCI). DESIGN Parallel-group randomized controlled trial. METHODS Individuals with chronic (≥ 18 months) incomplete SCI (level C2 to T12, AIS C or D) were recruited and randomized to FES-assisted walking (intervention), or aerobic and resistance training (control) sessions thrice-weekly for 16 weeks. Whole body and leg lean mass and whole body fat mass, measured with dual-energy X-ray absorptiometry, and lower-limb muscle cross-sectional area (CSA) and fat CSA, measured with peripheral computed tomography were assessed at baseline, 4 months, and 12 months. Intention-to-treat analyses using repeated measures general linear models were used to assess between-group differences. RESULTS Thirty-four individuals were randomized (17 per group); 27 remained at 12 months. There were no significant main effects of FES-assisted walking on body composition variables in intention-to-treat analyses with group means. There was a significant group-by-time interaction for muscle area from baseline to 12 months (P = 0.04). Intention-to-treat analysis of muscle area change scores between baseline and 12 months revealed a significant difference between groups (mean (SD) muscle area change score 212 (517) mm(s) for FES, -136 (268) mm(s) for control, P = 0.026). There were 13 side effects or adverse events deemed related to study participation (7 intervention, 5 control); most were resolved with modifications to the protocol. One fainting episode resulted in a hospital visit and study withdrawal. CONCLUSIONS Thrice-weekly FES-assisted walking exercise over 4 months did not result in a change in body composition in individuals with chronic, motor incomplete C2 to T12 SCI (AIS classification C and D). However, longer-term follow-up revealed that it might maintain muscle area.
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Affiliation(s)
- Lora Giangregorio
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada.
| | - Catharine Craven
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario
| | - Kieva Richards
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario
| | - Naaz Kapadia
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario
| | - Sander L. Hitzig
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario; and Health Outcomes and PharmacoEconomics (HOPE) Research Centre, Sunnybrook Health Sciences Centre, Toronto, Canada
| | - Kei Masani
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario
| | - Milos R. Popovic
- Department of Medicine Toronto Rehabilitation Institute – University Health Network, University of Toronto, Toronto, Ontario; and Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
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McHenry CL, Shields RK. A biomechanical analysis of exercise in standing, supine, and seated positions: Implications for individuals with spinal cord injury. J Spinal Cord Med 2012; 35:140-7. [PMID: 22507023 PMCID: PMC3324830 DOI: 10.1179/2045772312y.0000000011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
CONTEXT/OBJECTIVE The distal femur is the primary fracture site in patients with osteoporosis after spinal cord injury (SCI). OBJECTIVE To mathematically compare the compression and shear forces at the distal femur during quadriceps stimulation in the standing, supine, and seated positions. A force analysis across these positions may be a consideration for people with SCI during neuromuscular electrical stimulation of the quadriceps. DESIGN A biomechanical model. SETTING Research laboratory. OUTCOME MEASURES Compression and shear forces from the standing, supine, and seated biomechanical models at the distal femur during constant loads generated by the quadriceps muscles. RESULTS The standing model estimated the highest compressive force at 240% body weight and the lowest shear force of 24% body weight at the distal femur compared with the supine and seated models. The supine model yielded a compressive force of 191% body weight with a shear force of 62% body weight at the distal femur. The seated model yielded the lowest compressive force of 139% body weight and the highest shear force of 215% body weight. CONCLUSIONS When inducing a range of forces in the quadriceps muscles, the seated position yields the highest shear forces and lowest compressive forces when compared with the supine and standing positions. Standing with isometric contractions generates the highest compressive loads and lowest shear forces. Early active resistive standing may provide the most effective means to prevent bone loss after SCI.
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Affiliation(s)
- Colleen L McHenry
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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Dudley-Javoroski S, Littmann AE, Chang SH, McHenry CL, Shields RK. Enhancing muscle force and femur compressive loads via feedback-controlled stimulation of paralyzed quadriceps in humans. Arch Phys Med Rehabil 2011; 92:242-9. [PMID: 21272720 DOI: 10.1016/j.apmr.2010.10.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 10/18/2010] [Accepted: 10/19/2010] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare paralyzed quadriceps force properties and femur compressive loads in an upright functional task during conventional constant-frequency stimulation and force feedback-modulated stimulation. DESIGN Crossover trial. SETTING Research laboratory. PARTICIPANTS Subjects (N=13; 12 men, 1 woman) with motor-complete spinal cord injury. INTERVENTIONS Subjects performed 2 bouts of 60 isometric quadriceps contractions while supported in a standing frame. On separate days, subjects received constant-frequency stimulation at 20Hz (CONST) or frequency-modulated stimulation triggered by a change in force (FDBCK). During FDBCK, a computer algorithm responded to each 10% reduction in force with a 20% increase in stimulation frequency. MAIN OUTCOME MEASURES A biomechanical model was used to derive compressive loads on the femur, with a target starting dose of load equal to 1.5 times body weight. RESULTS Peak quadriceps force and fatigue index were higher for FDBCK than CONST (P<.05). Within-train force decline was greater during FDBCK bouts, but mean force remained above CONST values (P<.05). As fatigue developed during repetitive stimulation, FDBCK was superior to CONST for maintenance of femur compressive loads (P<.05). CONCLUSIONS Feedback-modulated stimulation in electrically activated stance is a viable method to maximize the physiologic performance of paralyzed quadriceps muscle. Compared with CONST, FDBCK yielded compressive loads that were closer to a targeted dose of stress with known osteogenic potential. Optimization of muscle force with FDBCK may be a useful tactic for future training-based antiosteoporosis protocols.
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Affiliation(s)
- Shauna Dudley-Javoroski
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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Osteoporosis in Persons With Spinal Cord Injury: The Need for a Targeted Therapeutic Education. Arch Phys Med Rehabil 2011; 92:59-67. [DOI: 10.1016/j.apmr.2010.09.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 09/06/2010] [Accepted: 09/08/2010] [Indexed: 11/22/2022]
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Hamzaid NA, Davis G. Health and Fitness Benefits of Functional Electrical Stimulation-Evoked Leg Exercise for Spinal Cord–Injured Individuals. Top Spinal Cord Inj Rehabil 2009. [DOI: 10.1310/sci1404-88] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Screening and habituation of functional electrical stimulation-leg cycle ergometry for individuals with spinal cord injury: a pilot study. J Neurol Phys Ther 2009; 32:164-70. [PMID: 19265757 DOI: 10.1097/npt.0b013e31818de56f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To document the screening process and develop the habituation procedures prior to commencing a functional electrical stimulation leg cycle ergometry (FES-LCE) exercise program for individuals with spinal cord injury (SCI). DESIGN This was a prospective descriptive study of screening and habituation for FES-LCE exercise for people with chronic SCI (injury duration longer than one year). SETTING : Tertiary rehabilitation center. PARTICIPANTS Thirteen subjects with SCI (mean years since injury, 7; mean age, 34.8 years; injury range, C4-T10; 7 males). MAIN OUTCOME MEASURES Time to attain target cycle speed for 30 continuous minutes. RESULTS Six of the 13 subjects were not eligible to start the FES-LCE habituation program because of previous fragility fracture, excessive spasticity, pain, autonomic dysreflexia, or lack of electrical stimulation response because of lower motor neuron damage in individuals with low thoracic injuries (T11-12). Time to attain target cycle speed for 30 continuous minutes ranged from 30 to 779 minutes (1-31 training sessions). CONCLUSIONS Almost half of the individuals interested in participating in the FES-LCE exercise program did not pass the screening phase. Although the habituation phase was time-consuming for most of the participants who were able to use the FES-LCE, all reported few adverse effects to using the device once they completed this phase of training.
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Biering-Sørensen F, Hansen B, Lee BSB. Non-pharmacological treatment and prevention of bone loss after spinal cord injury: a systematic review. Spinal Cord 2009; 47:508-18. [PMID: 19172152 DOI: 10.1038/sc.2008.177] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Review the literature on non-pharmacological prevention and treatment of osteoporosis after spinal cord injury (SCI). METHODS PubMed, EMBASE and the Cochrane Controlled Trials Register were searched. All identified papers were read by title, abstract and full-length article when relevant. Hand search of the articles' sources identified additional papers. For included studies, the level of evidence was determined. RESULTS No studies conclusively showed an effective intervention. However, there are few randomized controlled trials (RCTs), and those that exist assess interventions and outcome measures that could be improved. Five studies on weight-bearing early post-injury are conflicting, but standing or walking may help retain bone mineral. In the chronic phase, there was no effect of weight bearing (12 studies). One study found that an early commencement of sports after SCI improved bone mineral, and the longer the period of athletic career, the higher the (leg) bone mineral. Early after SCI, there may be some effects of electrical stimulation (ES) (five studies). Chronic-phase ES studies vary (14 studies, including mixed periods after injury), but improvement is seen with longer period of training, or higher frequency or stimulus intensity. Improvements correspond to trabecular bone in the distal femur or proximal tibia. Impact vibration and pulsed electromagnetic fields may have some positive effects, whereas pulsed ultrasound does not. Six studies on the influence of spasticity show inconsistent results. CONCLUSIONS Bone mineral should be measured around the knee; the length and intensity of the treatment should be sufficiently long and high, respectively, and should commence early after SCI. If bone mineral is to remain, the stimulation has to be possibly continued for long term. In addition, RCTs are necessary.
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Frotzler A, Coupaud S, Perret C, Kakebeeke TH, Hunt KJ, Donaldson NDN, Eser P. High-volume FES-cycling partially reverses bone loss in people with chronic spinal cord injury. Bone 2008; 43:169-176. [PMID: 18440891 DOI: 10.1016/j.bone.2008.03.004] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Revised: 02/29/2008] [Accepted: 03/03/2008] [Indexed: 11/20/2022]
Abstract
Spinal cord injury (SCI) leads to severe bone loss in the paralysed limbs and to a resulting increased fracture risk thereof. Since long bone fractures can lead to comorbidities and a reduction in quality of life, it is important to improve bone strength in people with chronic SCI. In this prospective longitudinal cohort study, we investigated whether functional electrical stimulation (FES) induced high-volume cycle training can partially reverse the loss of bone substance in the legs after chronic complete SCI. Eleven participants with motor-sensory complete SCI (mean age 41.9+/-7.5 years; 11.0+/-7.1 years post injury) were recruited. After an initial phase of 14+/-7 weeks of FES muscle conditioning, participants performed on average 3.7+/-0.6 FES-cycling sessions per week, of 58+/-5 min each, over 12 months at each individual's highest power output. Bone and muscle parameters were investigated in the legs by means of peripheral quantitative computed tomography before the muscle conditioning (t1), and after six (t2) and 12 months (t3) of high-volume FES-cycle training. After 12 months of FES-cycling, trabecular and total bone mineral density (BMD) as well as total cross-sectional area in the distal femoral epiphysis increased significantly by 14.4+/-21.1%, 7.0+/-10.8% and 1.2+/-1.5%, respectively. Bone parameters in the femoral shaft showed small but significant decreases, with a reduction of 0.4+/-0.4% in cortical BMD, 1.8+/-3.0% in bone mineral content, and 1.5+/-2.1% in cortical thickness. These decreases mainly occurred between t1 and t2. No significant changes were found in any of the measured bone parameters in the tibia. Muscle CSA at the thigh increased significantly by 35.5+/-18.3%, while fat CSA at the shank decreased by 16.7+/-12.3%. Our results indicate that high-volume FES-cycle training leads to site-specific skeletal changes in the paralysed limbs, with an increase in bone parameters at the actively loaded distal femur but not the passively loaded tibia. Thus, we conclude that high-volume FES-induced cycle training has clinical relevance as it can partially reverse bone loss and thus may reduce fracture risk at this fracture prone site.
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Affiliation(s)
| | - Sylvie Coupaud
- Centre for Rehabilitation Engineering, Department of Mechanical Engineering, University of Glasgow, Glasgow, United Kingdom; Queen Elizabeth National Spinal Injuries Unit, Southern General Hospital, Glasgow, United Kingdom
| | | | | | - Kenneth J Hunt
- Centre for Rehabilitation Engineering, Department of Mechanical Engineering, University of Glasgow, Glasgow, United Kingdom; Queen Elizabeth National Spinal Injuries Unit, Southern General Hospital, Glasgow, United Kingdom
| | | | - Prisca Eser
- Clinic of Rheumatology and Clinical Immunology/Allergology, University Hospital Berne, Switzerland; Institute of Social and Preventive Medicine, University of Berne, Berne, Switzerland
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Dudley-Javoroski S, Littmann AE, Iguchi M, Shields RK. Doublet stimulation protocol to minimize musculoskeletal stress during paralyzed quadriceps muscle testing. J Appl Physiol (1985) 2008; 104:1574-82. [PMID: 18436697 DOI: 10.1152/japplphysiol.00892.2007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
With long-term electrical stimulation training, paralyzed muscle can serve as an effective load delivery agent for the skeletal system. Muscle adaptations to training, however, will almost certainly outstrip bone adaptations, exposing participants in training protocols to an elevated risk for fracture. Assessing the physiological properties of the chronically paralyzed quadriceps may transmit unacceptably high shear forces to the osteoporotic distal femur. We devised a two-pulse doublet strategy to measure quadriceps physiological properties while minimizing the peak muscle force. The purposes of the study were 1) to determine the repeatability of the doublet stimulation protocol, and 2) to compare this protocol among individuals with and without spinal cord injury (SCI). Eight individuals with SCI and four individuals without SCI underwent testing. The doublet force-frequency relationship shifted to the left after SCI, likely reflecting enhancements in the twitch-to-tetanus ratio known to exist in paralyzed muscle. Posttetanic potentiation occurred to a greater degree in subjects with SCI (20%) than in non-SCI subjects (7%). Potentiation of contractile rate occurred in both subject groups (14% and 23% for SCI and non-SCI, respectively). Normalized contractile speed (rate of force rise, rate of force fall) reflected well-known adaptations of paralyzed muscle toward a fast fatigable muscle. The doublet stimulation strategy provided repeatable and sensitive measurements of muscle force and speed properties that revealed meaningful differences between subjects with and without SCI. Doublet stimulation may offer a unique way to test muscle physiological parameters of the quadriceps in subjects with uncertain musculoskeletal integrity.
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Dose estimation and surveillance of mechanical loading interventions for bone loss after spinal cord injury. Phys Ther 2008; 88:387-96. [PMID: 18202080 PMCID: PMC3270311 DOI: 10.2522/ptj.20070224] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND PURPOSE The interpretation of the results of previous anti-osteoporosis interventions after spinal cord injury (SCI) is undermined by incomplete information about the intervention dose or patient adherence to dose requirements. Rehabilitation research as a whole traditionally has struggled with these same issues. The purpose of this case report is to offer proof of the concepts that careful dose selection and surveillance of patient adherence should be integral components in rehabilitation interventions. CASE DESCRIPTION A 21-year-old man with T4 complete paraplegia (7 weeks) enrolled in a unilateral soleus muscle electrical stimulation protocol. Compressive loads applied to the tibia approximated 1.4 times body weight. Over 4.8 years of home-based training, data logging software provided surveillance of adherence. Soleus muscle torque and fatigue index adaptations to training as well as bone mineral density (BMD) adaptations in the distal tibia were measured. OUTCOMES The patient performed nearly 8,000 soleus muscle contractions per month, with occasional fluctuations. Adherence tracking permitted intervention when adherence fell below acceptable values. The soleus muscle torque and fatigue index increased rapidly in response to training. The BMD of the untrained tibia declined approximately 14% per year. The BMD of the trained tibia declined only approximately 7% per year. The BMD was preferentially preserved in the posterior half of the tibia; this region experienced only a 2.6% annual decline. DISCUSSION Early administration of a load intervention, careful estimation of the loading dose, and detailed surveillance of patient adherence aided in the interpretation of a patient's adaptations to a mechanical load protocol. These concepts possess wider applicability to rehabilitation research and should be emphasized in future physical therapy investigations.
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Abstract
Spinal cord injury (SCI) leads to a partial or complete disruption of motor, sensory, and autonomic nerve pathways below the level of the lesion. In paraplegic patients, functional electrical stimulation (FES) was originally widely considered as a means to restore walking function but this was proved technically very difficult because of the numerous degrees of freedom involved in walking. FES cycling was developed for people with SCI and has the advantages that cycling can be maintained for reasonably long periods in trained muscles and the risk of falls is low. In the article, we review research findings relevant to the successful application of FES cycling including the effects on muscle size, strength and function, and the cardiovascular and bone changes. We also describe important practical considerations in FES cycling regarding the application of surface electrodes, training and setting up the stimulator limitations, implanted stimulators and FES cycling including FES cycling in groups and other FES exercises such as FES rowing.
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Affiliation(s)
- D J Newham
- Division of Applied Biomedical Research, School of Biomedical and Health Sciences, King's College London, London, UK
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Frey Law L, Shields R. Mathematical models of human paralyzed muscle after long-term training. J Biomech 2007; 40:2587-95. [PMID: 17316653 PMCID: PMC3272269 DOI: 10.1016/j.jbiomech.2006.12.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Accepted: 12/14/2006] [Indexed: 11/19/2022]
Abstract
Spinal cord injury (SCI) results in major musculoskeletal adaptations, including muscle atrophy, faster contractile properties, increased fatigability, and bone loss. The use of functional electrical stimulation (FES) provides a method to prevent paralyzed muscle adaptations in order to sustain force-generating capacity. Mathematical muscle models may be able to predict optimal activation strategies during FES, however muscle properties further adapt with long-term training. The purpose of this study was to compare the accuracy of three muscle models, one linear and two nonlinear, for predicting paralyzed soleus muscle force after exposure to long-term FES training. Further, we contrasted the findings between the trained and untrained limbs. The three models' parameters were best fit to a single force train in the trained soleus muscle (N=4). Nine additional force trains (test trains) were predicted for each subject using the developed models. Model errors between predicted and experimental force trains were determined, including specific muscle force properties. The mean overall error was greatest for the linear model (15.8%) and least for the nonlinear Hill Huxley type model (7.8%). No significant error differences were observed between the trained versus untrained limbs, although model parameter values were significantly altered with training. This study confirmed that nonlinear models most accurately predict both trained and untrained paralyzed muscle force properties. Moreover, the optimized model parameter values were responsive to the relative physiological state of the paralyzed muscle (trained versus untrained). These findings are relevant for the design and control of neuro-prosthetic devices for those with SCI.
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Affiliation(s)
| | - R.K. Shields
- Corresponding author. Tel.: +319335 9791; fax: +319 335 9707. (R.K. Shields)
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Abstract
BACKGROUND/OBJECTIVE This study examined magnitude and recovery of low-frequency fatigue (LFF) in the quadriceps after electrically stimulated contractions in spinal cord-injured (SCI) and able-bodied subjects. SUBJECTS Nine SCI (ASIA A-C, levels C5-T9, injured 13.6 +/- 12.2 years) and 9 sedentary able-bodied subjects completed this study. METHODS Fatigue was evoked in 1 thigh, and the nonfatigued leg served as a control. The fatigue test for able-bodied subjects lasted 15 minutes. For SCI, stimulation was adjusted so that the relative drop in force was matched to the able-bodied group. Force was assessed at 20 (P20) and 100 Hz (P100), and the ratio of P20/P100 was used to evaluate LFF in thighs immediately after, at 10, 20, and 60 minutes, and at 2, 4, 6, and 24 hours after a fatigue test. RESULTS The magnitude of LFF (up to 1 hour after fatigue) was not different between able-bodied and patients with SCI. However, recovery of LFF over 24 hours was greater in able-bodied compared with patients with SCI in both the experimental (P < 0.001) and control legs (P < 0.001). The able-bodied group showed a gradual recovery of LFF over time in the experimental leg, whereas the SCI group did not. CONCLUSIONS These results show that individuals with SCI are more susceptible to LFF than able-bodied subjects. In SCI, simply assessing LFF produced considerable LFF and accounted for a substantial portion of the response. We propose that muscle injury is causing the dramatic LFF in SCI, and future studies are needed to test whether "fatigue" in SCI is actually confounded by the effects of muscle injury.
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Affiliation(s)
- Edward Mahoney
- Department of Kinesiology, University of Georgia, Athens, Georgia, USA.
| | - Timothy W Puetz
- Department of Kinesiology, University of Georgia, Athens, Georgia
| | - Gary A Dudley
- Department of Kinesiology, University of Georgia, Athens, Georgia
,Crawford Research Center Shepherd Center, Atlanta, Georgia
| | - Kevin K McCully
- Department of Kinesiology, University of Georgia, Athens, Georgia
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Shields RK, Dudley-Javoroski S, Cole KR. Feedback-controlled stimulation enhances human paralyzed muscle performance. J Appl Physiol (1985) 2006; 101:1312-9. [PMID: 16809630 PMCID: PMC3270310 DOI: 10.1152/japplphysiol.00385.2006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronically paralyzed muscle requires extensive training before it can deliver a therapeutic dose of repetitive stress to the musculoskeletal system. Neuromuscular electrical stimulation, under feedback control, may subvert the effects of fatigue, yielding more rapid and extensive adaptations to training. The purposes of this investigation were to 1) compare the effectiveness of torque feedback-controlled (FDBCK) electrical stimulation with classic open-loop constant-frequency (CONST) stimulation, and 2) ascertain which of three stimulation strategies best maintains soleus torque during repetitive stimulation. When torque declined by 10%, the FDBCK protocol modulated the base stimulation frequency in three ways: by a fixed increase, by a paired pulse (doublet) at the beginning of the stimulation train, and by a fixed decrease. The stimulation strategy that most effectively restored torque continued for successive contractions. This process repeated each time torque declined by 10%. In fresh muscle, FDBCK stimulation offered minimal advantage in maintaining peak torque or mean torque over CONST stimulation. As long-duration fatigue developed in subsequent bouts, FDBCK stimulation became most effective ( approximately 40% higher final normalized torque than CONST). The high-frequency strategy was selected approximately 90% of the time, supporting that excitation-contraction coupling compromise and not neuromuscular transmission failure contributed to fatigue of paralyzed muscle. Ideal stimulation strategies may vary according to the site of fatigue; this stimulation approach offered the advantage of online modulation of stimulation strategies in response to fatigue conditions. Based on stress-adaptation principles, FDBCK-controlled stimulation may enhance training effects in chronically paralyzed muscle.
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Affiliation(s)
- Richard K Shields
- Graduate Program in Physical Therapy and Rehabilitation Science, The University of Iowa, Iowa City, IA 52242-1190, USA.
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Frey Law LA, Shields RK. Predicting human chronically paralyzed muscle force: a comparison of three mathematical models. J Appl Physiol (1985) 2006; 100:1027-36. [PMID: 16306255 PMCID: PMC3274555 DOI: 10.1152/japplphysiol.00935.2005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic spinal cord injury (SCI) induces detrimental musculoskeletal adaptations that adversely affect health status, ranging from muscle paralysis and skin ulcerations to osteoporosis. SCI rehabilitative efforts may increasingly focus on preserving the integrity of paralyzed extremities to maximize health quality using electrical stimulation for isometric training and/or functional activities. Subject-specific mathematical muscle models could prove valuable for predicting the forces necessary to achieve therapeutic loading conditions in individuals with paralyzed limbs. Although numerous muscle models are available, three modeling approaches were chosen that can accommodate a variety of stimulation input patterns. To our knowledge, no direct comparisons between models using paralyzed muscle have been reported. The three models include 1) a simple second-order linear model with three parameters and 2) two six-parameter nonlinear models (a second-order nonlinear model and a Hill-derived nonlinear model). Soleus muscle forces from four individuals with complete, chronic SCI were used to optimize each model's parameters (using an increasing and decreasing frequency ramp) and to assess the models' predictive accuracies for constant and variable (doublet) stimulation trains at 5, 10, and 20 Hz in each individual. Despite the large differences in modeling approaches, the mean predicted force errors differed only moderately (8-15% error; P=0.0042), suggesting physiological force can be adequately represented by multiple mathematical constructs. The two nonlinear models predicted specific force characteristics better than the linear model in nearly all stimulation conditions, with minimal differences between the two nonlinear models. Either nonlinear mathematical model can provide reasonable force estimates; individual application needs may dictate the preferred modeling strategy.
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Affiliation(s)
- Laura A Frey Law
- Graduate Program in Physical Therapy and Rehabilitation Science, 1-252 Medical Education Bldg., The Univ. of Iowa, Iowa City, IA 52242, USA
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Shields RK, Dudley-Javoroski S. Musculoskeletal plasticity after acute spinal cord injury: effects of long-term neuromuscular electrical stimulation training. J Neurophysiol 2006; 95:2380-90. [PMID: 16407424 PMCID: PMC3298883 DOI: 10.1152/jn.01181.2005] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Maintaining the physiologic integrity of paralyzed limbs may be critical for those with spinal cord injury (SCI) to be viable candidates for a future cure. No long-term intervention has been tested to attempt to prevent the severe musculoskeletal deterioration that occurs after SCI. The purposes of this study were to determine whether a long-term neuromuscular electrical stimulation training program can preserve the physiological properties of the plantar flexor muscles (peak torque, fatigue index, torque-time integral, and contractile speed) as well as influence distal tibia trabecular bone mineral density (BMD). Subjects began unilateral plantar flexion electrical stimulation training within 6 wk after SCI while the untrained leg served as a control. Mean compliance for the 2-yr training program was 83%. Mean estimated compressive loads delivered to the tibia were approximately 1-1.5 times body weight. The training protocol yielded significant trained versus untrained limb differences for torque (+24%), torque-time integral (+27%), fatigue index (+50%), torque rise time (+45%), and between-twitch fusion (+15%). These between-limb differences were even greater when measured at the end of a repetitive stimulation protocol (125 contractions). Peripheral quantitative computed tomography revealed 31% higher distal tibia trabecular BMD in trained limbs than in untrained limbs. The intervention used in this study was sufficient to limit many of the deleterious muscular and skeletal adaptations that normally occur after SCI. Importantly, this method of load delivery was feasible and may serve as the basis for an intervention to preserve the musculoskeletal properties of individuals with SCI.
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Affiliation(s)
- Richard K Shields
- Graduate Program in Physical Therapy and Rehabilitation Science, The University of Iowa, Iowa City, IA 52242-1190, USA.
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Giangregorio L, McCartney N. Bone loss and muscle atrophy in spinal cord injury: epidemiology, fracture prediction, and rehabilitation strategies. J Spinal Cord Med 2006; 29:489-500. [PMID: 17274487 PMCID: PMC1949032 DOI: 10.1080/10790268.2006.11753898] [Citation(s) in RCA: 202] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Individuals with spinal cord injury (SCI) often experience bone loss and muscle atrophy. Muscle atrophy can result in reduced metabolic rate and increase the risk of metabolic disorders. Sublesional osteoporosis predisposes individuals with SCI to an increased risk of low-trauma fracture. Fractures in people with SCI have been reported during transfers from bed to chair, and while being turned in bed. The bone loss and muscle atrophy that occur after SCI are substantial and may be influenced by factors such as completeness of injury or time postinjury. A number of interventions, including standing, electrically stimulated cycling or resistance training, and walking exercises have been explored with the aim of reducing bone loss and/or increasing bone mass and muscle mass in individuals with SCI. Exercise with electrical stimulation appears to increase muscle mass and/or prevent atrophy, but studies investigating its effect on bone are conflicting. Several methodological limitations in exercise studies with individuals with SCI to date limit our ability to confirm the utility of exercise for improving skeletal status. The impact of standing or walking exercises on muscle and bone has not been well established. Future research should carefully consider the study design, skeletal measurement sites, and the measurement techniques used in order to facilitate sound conclusions.
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Affiliation(s)
- Lora Giangregorio
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada.
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Abstract
Spinal cord injury is a catastrophic event that immeasurably alters activity and health. Depending on the level and severity of injury, functional and homeostatic decline of many body systems can be anticipated in a large segment of the paralyzed population. The level of physical inactivity and deconditioning imposed by SCI profoundly contrasts the preinjury state in which most individuals are relatively young and physically active. Involvement in sports, recreation, and therapeutic exercise is commonly restricted after SCI by loss of voluntary motor control, as well as autonomic dysfunction, altered fuel homeostasis, inefficient temperature regulation, and early-onset muscle fatigue. Participation in exercise activities also may require special adaptive equipment and, in some instances, the use of electrical current either with or without computerized control. Notwithstanding these limitations, considerable evidence supports the belief that recreational and therapeutic exercise improves the physical and emotional well-being of participants with SCI. This article will examine multisystem decline and the need for exercise after SCI. It will further examine how exercise might be used as a tool to enhance health by slowing multisystem medical complications unique to those with SCI. As imprudent exercise recommendations may pose avoidable risks of incipient disability, orthopedic deterioration, or pain, the special risks of exercise misuse in those with SCI will be discussed.
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Affiliation(s)
- Mark S Nash
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, FL, USA.
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Frey Law LA, Shields RK. Mathematical models use varying parameter strategies to represent paralyzed muscle force properties: a sensitivity analysis. J Neuroeng Rehabil 2005; 2:12. [PMID: 15927064 PMCID: PMC1175855 DOI: 10.1186/1743-0003-2-12] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Accepted: 05/31/2005] [Indexed: 11/10/2022] Open
Abstract
Background Mathematical muscle models may be useful for the determination of appropriate musculoskeletal stresses that will safely maintain the integrity of muscle and bone following spinal cord injury. Several models have been proposed to represent paralyzed muscle, but there have not been any systematic comparisons of modelling approaches to better understand the relationships between model parameters and muscle contractile properties. This sensitivity analysis of simulated muscle forces using three currently available mathematical models provides insight into the differences in modelling strategies as well as any direct parameter associations with simulated muscle force properties. Methods Three mathematical muscle models were compared: a traditional linear model with 3 parameters and two contemporary nonlinear models each with 6 parameters. Simulated muscle forces were calculated for two stimulation patterns (constant frequency and initial doublet trains) at three frequencies (5, 10, and 20 Hz). A sensitivity analysis of each model was performed by altering a single parameter through a range of 8 values, while the remaining parameters were kept at baseline values. Specific simulated force characteristics were determined for each stimulation pattern and each parameter increment. Significant parameter influences for each simulated force property were determined using ANOVA and Tukey's follow-up tests (α ≤ 0.05), and compared to previously reported parameter definitions. Results Each of the 3 linear model's parameters most clearly influence either simulated force magnitude or speed properties, consistent with previous parameter definitions. The nonlinear models' parameters displayed greater redundancy between force magnitude and speed properties. Further, previous parameter definitions for one of the nonlinear models were consistently supported, while the other was only partially supported by this analysis. Conclusion These three mathematical models use substantially different strategies to represent simulated muscle force. The two contemporary nonlinear models' parameters have the least distinct associations with simulated muscle force properties, and the greatest parameter role redundancy compared to the traditional linear model.
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Affiliation(s)
- Laura A Frey Law
- Graduate Program in Physical Therapy and Rehabilitation Science, 1-252 Medical Education Bldg., The University of Iowa, Iowa City, IA, USA
| | - Richard K Shields
- Graduate Program in Physical Therapy and Rehabilitation Science, 1-252 Medical Education Bldg., The University of Iowa, Iowa City, IA, USA
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