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Abstract
Cerebral palsy (CP) is a lifespan motor disorder arising from damage to the developing brain before or shortly after birth. People with CP may experience problems with muscle coordination and difficulties with the organization and processing of sensory information. Functional mobility is impaired and commonly influenced by spasticity and musculoskeletal system problems such as contractures or bony torsion. Around 60% of individuals with CP are able to walk independently or with aids when entering adulthood. However, many adults with CP experience increasing balance and mobility dysfunction associated with premature aging. Falls and reduced falls efficacy are commonly experienced, with associated physical and psychosocial consequences. There is evidence that ambulant adults with CP may be able to enhance their functional balance and mobility as a result of an individualized exercise program of sufficient duration and intensity. However, whether such programs result in a reduction in falls is unknown. Given the high number of falls with injury experienced by this population, attention to fall risk factors and provision of basic fall prevention strategies are warranted.
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Affiliation(s)
- Prue Morgan
- Physiotherapy Department, School of Primary and Allied Health Care, Monash University, Frankston, VIC, Australia.
| | - Jennifer L McGinley
- Physiotherapy Department, Melbourne School of Health Sciences, University of Melbourne, Parkville, VIC, Australia
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202
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Obst SJ, Boyd R, Read F, Barber L. Quantitative 3-D Ultrasound of the Medial Gastrocnemius Muscle in Children with Unilateral Spastic Cerebral Palsy. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:2814-2823. [PMID: 28967503 DOI: 10.1016/j.ultrasmedbio.2017.08.929] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 08/07/2017] [Accepted: 08/13/2017] [Indexed: 06/07/2023]
Abstract
Three-dimensional ultrasound (3-DUS) was used to examine the size and appearance of the medial gastrocnemius (MG) muscle in children with unilateral cerebral palsy (CP). Twenty-six children with CP and 10 typically developing (TD) children participated. Three-dimensional US images of both limbs in children with CP and the right limb in TD children were analysed using quantitative methods to determine muscle volume, global echo intensity, global echo pattern and regional echo intensity. Significant differences in MG volume and all echo parameters were found between TD and CP children. The more involved limb was smaller and had higher echo intensity and a more heterogenous echo pattern compared with the TD group. Compared with that of the more involved limb, the MG of the less involved limb was larger but had a similar echo appearance. The MG of both limbs in children with unilateral spastic CP is smaller and, based on quantitative ultrasound, structurally different from that of TD children.
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Affiliation(s)
- Steven J Obst
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia; School of Health, Medical and Applied Sciences, Central Queensland University, Bundaberg, Queensland, Australia.
| | - Roslyn Boyd
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Felicity Read
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Lee Barber
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
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203
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Mukund K, Subramaniam S. Co-expression Network Approach Reveals Functional Similarities among Diseases Affecting Human Skeletal Muscle. Front Physiol 2017; 8:980. [PMID: 29249983 PMCID: PMC5717538 DOI: 10.3389/fphys.2017.00980] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 11/16/2017] [Indexed: 12/27/2022] Open
Abstract
Diseases affecting skeletal muscle exhibit considerable heterogeneity in intensity, etiology, phenotypic manifestation and gene expression. Systems biology approaches using network theory, allows for a holistic understanding of functional similarities amongst diseases. Here we propose a co-expression based, network theoretic approach to extract functional similarities from 20 heterogeneous diseases comprising of dystrophinopathies, inflammatory myopathies, neuromuscular, and muscle metabolic diseases. Utilizing this framework we identified seven closely associated disease clusters with 20 disease pairs exhibiting significant correlation (p < 0.05). Mapping the diseases onto a human protein-protein interaction network enabled the inference of a common program of regulation underlying more than half the muscle diseases considered here and referred to as the “protein signature.” Enrichment analysis of 17 protein modules identified as part of this signature revealed a statistically non-random dysregulation of muscle bioenergetic pathways and calcium homeostasis. Further, analysis of mechanistic similarities of less explored significant disease associations [such as between amyotrophic lateral sclerosis (ALS) and cerebral palsy (CP)] using a proposed “functional module” framework revealed adaptation of the calcium signaling machinery. Integrating drug-gene information into the quantitative framework highlighted the presence of therapeutic opportunities through drug repurposing for diseases affecting the skeletal muscle.
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Affiliation(s)
- Kavitha Mukund
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, United States
| | - Shankar Subramaniam
- Departments Cellular and Molecular Medicine, Computer Science and Engineering, University of California, San Diego, La Jolla, CA, United States
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204
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Pingel J, Suhr F. Are mechanically sensitive regulators involved in the function and (patho)physiology of cerebral palsy-related contractures? J Muscle Res Cell Motil 2017; 38:317-330. [PMID: 29190010 DOI: 10.1007/s10974-017-9489-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 11/21/2017] [Indexed: 12/17/2022]
Abstract
Skeletal muscle tissue is mechanosensitive, as it is able to sense mechanical impacts and to translate these into biochemical signals making the tissue adapt. Among its mechanosensitive nature, skeletal muscle tissue is the largest metabolic organ of the human body. Disturbances in skeletal muscle mechanosensing and metabolism cause and contribute to many diseases, i.e. muscular dystrophies/myopathies, cardiovascular diseases, COPD or diabetes mellitus type 2. A less commonly focused muscle-related disorder is clinically known as muscle contractures that derive from cerebral palsy (CP) conditions in young and adults. Muscle contractures are characterized by gradually increasing passive muscle stiffness resulting in complete fixation of joints. Different mechanisms have been identified in CP-related contractures, i.e. altered calcium handling, altered metabolism or altered titin regulation. The muscle-related extracellular matrix (ECM), specifically collagens, plays a role in CP-related contractures. Herein, we focus on mechanically sensitive complexes, known as costameres (Cstms), and discuss their potential role in CP-related contractures. We extend our discussion to the ECM due to the limited knowledge of its role in CP-related contractures. The aims of this review are (1) to summarize CP-related contracture mechanisms, (2) to raise novel hypotheses on the genesis of contractures with a focus on Cstms, and (3) to stimulate novel approaches to study CP-related contractures.
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Affiliation(s)
- Jessica Pingel
- Motor Control Lab, Department of Neuroscience and Pharmacology, University of Copenhagen, Blegdamsvej 3b, 2200, Copenhagen N, Denmark.
| | - Frank Suhr
- Exercise Physiology Research Group, Department of Movement Sciences, Biomedical Sciences Group, KU Leuven, Tervuursevest 101, box 1500, 3001, Leuven, Belgium.
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205
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Passive material properties of stroke-impaired plantarflexor and dorsiflexor muscles. Clin Biomech (Bristol, Avon) 2017; 49:48-55. [PMID: 28866442 PMCID: PMC5681874 DOI: 10.1016/j.clinbiomech.2017.08.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 08/02/2017] [Accepted: 08/23/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Following a stroke, intrinsic muscle properties such as stiffness may be altered, which is accompanied by increased spasticity and contractures. Previously, quantification of muscle stiffness has been based off of indirect measurements. Using shear wave ultrasound elastography, direct measurements of muscle material properties can be made. METHODS Our aim was to evaluate material properties, specifically passive stiffness, using shear wave ultrasound elastography across a range of muscle lengths, in the medial gastrocnemius and the tibialis anterior in chronic stroke survivors. FINDINGS Our main results show significant increases of 27.7% and 26.9% in shear wave velocity of stroke-impaired medial gastrocnemius compared to the unimpaired contralateral side at 90° ankle angle (P=0.033) and 15° plantarflexion (P=0.001), respectively. However, no significant difference was found in the tibialis anterior between the two sides. Relatively weak correlations were found between SW velocity in the medial gastrocnemius and joint stiffness for both the non-paretic (ρ=0.384, P=0.001), and paretic side (ρ=0.363, P=0.002). Additionally, muscle stiffness estimates of stroke-impaired tibialis anterior from joint torque and angle measurements were significantly greater by 23.1% (P=0.033) than the unimpaired contralateral side. However, no significant difference was found in the medial gastrocnemius. INTERPRETATION These results indicate that there are non-uniform changes in passive stiffness of stroke-impaired muscle. Therefore, muscles need to be evaluated individually to assess alterations. Additionally, interpretation of joint-based calculations of muscle stiffness should be made cautiously. Having the ability to non-invasively assess muscle stiffness adaptations in vivo would aid in prognosis, evaluation, and treatment following a stroke.
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206
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Lieber RL, Roberts TJ, Blemker SS, Lee SSM, Herzog W. Skeletal muscle mechanics, energetics and plasticity. J Neuroeng Rehabil 2017; 14:108. [PMID: 29058612 PMCID: PMC5651624 DOI: 10.1186/s12984-017-0318-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 10/05/2017] [Indexed: 01/06/2023] Open
Abstract
The following papers by Richard Lieber (Skeletal Muscle as an Actuator), Thomas Roberts (Elastic Mechanisms and Muscle Function), Silvia Blemker (Skeletal Muscle has a Mind of its Own: a Computational Framework to Model the Complex Process of Muscle Adaptation) and Sabrina Lee (Muscle Properties of Spastic Muscle (Stroke and CP) are summaries of their representative contributions for the session on skeletal muscle mechanics, energetics and plasticity at the 2016 Biomechanics and Neural Control of Movement Conference (BANCOM 2016). Dr. Lieber revisits the topic of sarcomere length as a fundamental property of skeletal muscle contraction. Specifically, problems associated with sarcomere length non-uniformity and the role of sarcomerogenesis in diseases such as cerebral palsy are critically discussed. Dr. Roberts then makes us aware of the (often neglected) role of the passive tissues in muscles and discusses the properties of parallel elasticity and series elasticity, and their role in muscle function. Specifically, he identifies the merits of analyzing muscle deformations in three dimensions (rather than just two), because of the potential decoupling of the parallel elastic element length from the contractile element length, and reviews the associated implications for the architectural gear ratio of skeletal muscle contraction. Dr. Blemker then tackles muscle adaptation using a novel way of looking at adaptive processes and what might drive adaptation. She argues that cells do not have pre-programmed behaviors that are controlled by the nervous system. Rather, the adaptive responses of muscle fibers are determined by sub-cellular signaling pathways that are affected by mechanical and biochemical stimuli; an exciting framework with lots of potential. Finally, Dr. Lee takes on the challenging task of determining human muscle properties in vivo. She identifies the dilemma of how we can demonstrate the effectiveness of a treatment, specifically in cases of muscle spasticity following stroke or in children with cerebral palsy. She then discusses the merits of ultrasound based elastography, and the clinical possibilities this technique might hold. Overall, we are treated to a vast array of basic and clinical problems in skeletal muscle mechanics and physiology, with some solutions, and many suggestions for future research.
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Affiliation(s)
- Richard L Lieber
- Rehabilitation Institute of Chicago, Chicago, USA.,Northwestern University, Evanston, USA
| | | | | | | | - Walter Herzog
- University of Calgary, Faculty of Kinesiology, Calgary, Canada.
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207
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Lerner ZF, Damiano DL, Bulea TC. The Effects of Exoskeleton Assisted Knee Extension on Lower-Extremity Gait Kinematics, Kinetics, and Muscle Activity in Children with Cerebral Palsy. Sci Rep 2017; 7:13512. [PMID: 29044202 PMCID: PMC5647342 DOI: 10.1038/s41598-017-13554-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/12/2017] [Indexed: 02/07/2023] Open
Abstract
Individuals with cerebral palsy often exhibit crouch gait, a debilitating and inefficient walking pattern marked by excessive knee flexion that worsens with age. To address the need for improved treatment, we sought to evaluate if providing external knee extension assistance could reduce the excessive burden placed on the knee extensor muscles as measured by knee moments. We evaluated a novel pediatric exoskeleton designed to provide appropriately-timed extensor torque to the knee joint during walking in a multi-week exploratory clinical study. Seven individuals (5-19 years) with mild-moderate crouch gait from cerebral palsy (GMFCS I-II) completed the study. For six participants, powered knee extension assistance favorably reduced the excessive stance-phase knee extensor moment present during crouch gait by a mean of 35% in early stance and 76% in late stance. Peak stance-phase knee and hip extension increased by 12° and 8°, respectively. Knee extensor muscle activity decreased slightly during exoskeleton-assisted walking compared to baseline, while knee flexor activity was elevated in some participants. These findings support the use of wearable exoskeletons for the management of crouch gait and provide insights into their future implementation.
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Affiliation(s)
- Zachary F Lerner
- Functional and Applied Biomechanics Section, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA
- Department of Mechanical Engineering, Northern Arizona University, Flagstaff, AZ, USA
| | - Diane L Damiano
- Functional and Applied Biomechanics Section, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA
| | - Thomas C Bulea
- Functional and Applied Biomechanics Section, Rehabilitation Medicine Department, National Institutes of Health, Bethesda, MD, USA.
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208
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Yucesoy CA, Temelli Y, Ateş F. Intra-operatively measured spastic semimembranosus forces of children with cerebral palsy. J Electromyogr Kinesiol 2017; 36:49-55. [DOI: 10.1016/j.jelekin.2017.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 05/24/2017] [Accepted: 07/10/2017] [Indexed: 11/30/2022] Open
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209
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Frisk RF, Jensen P, Kirk H, Bouyer LJ, Lorentzen J, Nielsen JB. Contribution of sensory feedback to plantar flexor muscle activation during push-off in adults with cerebral palsy. J Neurophysiol 2017; 118:3165-3174. [PMID: 28904105 DOI: 10.1152/jn.00508.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 12/25/2022] Open
Abstract
Exaggerated sensory activity has been assumed to contribute to functional impairment following lesion of the central motor pathway. However, recent studies have suggested that sensory contribution to muscle activity during gait is reduced in stroke patients and children with cerebral palsy (CP). We investigated whether this also occurs in CP adults and whether daily treadmill training is accompanied by alterations in sensory contribution to muscle activity. Seventeen adults with CP and 12 uninjured individuals participated. The participants walked on a treadmill while a robotized ankle-foot orthosis applied unload perturbations at the ankle, thereby removing sensory feedback naturally activated during push-off. Reduction of electromyographic (EMG) activity in the soleus muscle caused by unloads was compared and related to kinematics and ankle joint stiffness measurements. Similar measures were obtained after 6 wk of gait training. We found that sensory contribution to soleus EMG activation was reduced in CP adults compared with uninjured adults. The lowest contribution of sensory feedback was found in participants with lowest maximal gait speed. This was related to increased ankle plantar flexor stiffness. Six weeks of gait training did not alter the contribution of sensory feedback. We conclude that exaggerated sensory activity is unlikely to contribute to impaired gait in CP adults, because sensory contribution to muscle activity during gait was reduced compared with in uninjured individuals. Increased passive stiffness around the ankle joint is likely to diminish sensory feedback during gait so that a larger part of plantar flexor muscle activity must be generated by descending motor commands.NEW & NOTEWORTHY Findings suggest that adults with cerebral palsy have less contribution of sensory feedback to ongoing soleus muscle activation during push-off than uninjured individuals. Increased passive stiffness around the ankle joint is likely to diminish sensory feedback during gait, and/or sensory feedback is less integrated with central motor commands in the activation of spinal motor neurons. Consequently, muscle activation must to a larger extent rely on descending drive, which is already decreased because of the cerebral lesion.
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Affiliation(s)
- Rasmus F Frisk
- Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark; .,University College Zealand, Roskilde, Denmark.,Elsass Institute, Charlottenlund, Denmark
| | - Peter Jensen
- Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Kirk
- Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark.,Elsass Institute, Charlottenlund, Denmark
| | - Laurent J Bouyer
- CIRRIS-Department of Rehabilitation, Université Laval, Quebec City, Canada; and
| | - Jakob Lorentzen
- Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark.,Elsass Institute, Charlottenlund, Denmark
| | - Jens B Nielsen
- Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark.,Elsass Institute, Charlottenlund, Denmark
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210
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Bilgici MC, Bekci T, Ulus Y, Ozyurek H, Aydin OF, Tomak L, Selcuk MB. Quantitative assessment of muscular stiffness in children with cerebral palsy using acoustic radiation force impulse (ARFI) ultrasound elastography. J Med Ultrason (2001) 2017; 45:295-300. [DOI: 10.1007/s10396-017-0824-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 08/07/2017] [Indexed: 01/22/2023]
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211
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Discher DE, Smith L, Cho S, Colasurdo M, García AJ, Safran S. Matrix Mechanosensing: From Scaling Concepts in 'Omics Data to Mechanisms in the Nucleus, Regeneration, and Cancer. Annu Rev Biophys 2017; 46:295-315. [PMID: 28532215 DOI: 10.1146/annurev-biophys-062215-011206] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Many of the most important molecules of life are polymers. In animals, the most abundant of the proteinaceous polymers are the collagens, which constitute the fibrous matrix outside cells and which can also self-assemble into gels. The physically measurable stiffness of gels, as well as tissues, increases with the amount of collagen, and cells seem to sense this stiffness. An understanding of this mechanosensing process in complex tissues, including fibrotic disease states with high collagen, is now utilizing 'omics data sets and is revealing polymer physics-type, nonlinear scaling relationships between concentrations of seemingly unrelated biopolymers. The nuclear structure protein lamin A provides one example, with protein and transcript levels increasing with collagen 1 and tissue stiffness, and with mechanisms rooted in protein stabilization induced by cytoskeletal stress. Physics-based models of fibrous matrix, cytoskeletal force dipoles, and the lamin A gene circuit illustrate the wide range of testable predictions emerging for tissues, cell cultures, and even stem cell-based tissue regeneration. Beyond the epigenetics of mechanosensing, the scaling in cancer of chromosome copy number variations and other mutations with tissue stiffness suggests that genomic changes are occurring by mechanogenomic processes that now require elucidation.
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Affiliation(s)
- Dennis E Discher
- Molecular and Cell Biophysics Lab, University of Pennsylvania, Philadelphia, Pennsylvania 19104;
| | - Lucas Smith
- Molecular and Cell Biophysics Lab, University of Pennsylvania, Philadelphia, Pennsylvania 19104;
| | - Sangkyun Cho
- Molecular and Cell Biophysics Lab, University of Pennsylvania, Philadelphia, Pennsylvania 19104;
| | - Mark Colasurdo
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Andrés J García
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Sam Safran
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovet 76100, Israel
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212
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Barber L, Carty C, Modenese L, Walsh J, Boyd R, Lichtwark G. Medial gastrocnemius and soleus muscle-tendon unit, fascicle, and tendon interaction during walking in children with cerebral palsy. Dev Med Child Neurol 2017; 59:843-851. [PMID: 28369824 DOI: 10.1111/dmcn.13427] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/07/2017] [Indexed: 11/28/2022]
Abstract
AIM This study investigates the in vivo function of the medial gastrocnemius and soleus muscle-tendon units (MTU), fascicles, and tendons during walking in children with cerebral palsy (CP) and an equinus gait pattern. METHOD Fourteen children with CP (9 males, 5 females; mean age 10y 6mo, standard deviation [SD] 2y 11mo; GMFCS level I=8, II=6), and 10 typically developing (6 males, 4 females; mean age 10y, SD 2y 1mo) undertook full body 3D gait analysis and simultaneous B-mode ultrasound images of the medial gastrocnemius and soleus fascicles during level walking. Fascicle lengths were analysed using a semi-automated tracking algorithm and MTUs using OpenSim. Statistical parametric mapping (two-sample t-test) was used to compare differences between groups (p<0.05). RESULTS In the CP group medial gastrocnemius fascicles lengthened during mid-stance gait and remained longer into late-stance compared to the typically developing group (p<0.001). CP medial gastrocnemius fascicles shortened less during stance (1.16mm [SD 1.47mm]) compared to the typically developing group (4.48mm [SD 1.94mm], p<0.001). In the CP group the medial gastrocnemius and soleus MTU and tendon were longer during early- and mid-stance (p<0.001). Ankle power during push-off (p=0.015) and positive work (p<0.002) and net work (p<0.001) were significantly lower in the CP group. INTERPRETATION Eccentric action of the CP medial gastrocnemius muscle fascicles during mid-stance walking is consistent with reduced volume and neuromuscular control of impaired muscle. Reduced ankle push-off power and positive work in the children with CP may be attributed to reduced active medial gastrocnemius fascicle shortening. These findings suggest a reliance on passive force generation for forward propulsion during equinus gait.
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Affiliation(s)
- Lee Barber
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Australia
| | - Chris Carty
- Queensland Children's Motion Analysis Service, Children's Health Queensland Hospital and Health Service, Brisbane, Australia.,Centre for Musculoskeletal Research, Menzies Health Institute Queensland, Gold Coast, Australia
| | - Luca Modenese
- Centre for Musculoskeletal Research, Menzies Health Institute Queensland, Gold Coast, Australia.,Department of Mechanical Engineering and INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, UK
| | - John Walsh
- Queensland Children's Motion Analysis Service, Children's Health Queensland Hospital and Health Service, Brisbane, Australia
| | - Roslyn Boyd
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Australia
| | - Glen Lichtwark
- School of Human Movement Studies, The University of Queensland, St Lucia, Australia
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213
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Martín Lorenzo T, Albi Rodríguez G, Rocon E, Martínez Caballero I, Lerma Lara S. Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children: A cross-sectional study. Medicine (Baltimore) 2017; 96:e7572. [PMID: 28723790 PMCID: PMC5521930 DOI: 10.1097/md.0000000000007572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles' force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (-) r(14) = -0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide greater insight on the relationship between relative fascicle excursions and joint function.
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Affiliation(s)
- Teresa Martín Lorenzo
- Laboratorio de Análisis del Movimiento, Hospital Infantil Universitario Niño Jesús
- Facultad de Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón
| | - Gustavo Albi Rodríguez
- Servicio de Radiodiagnóstico, Hospital Infantil Universitario Niño Jesús
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid
| | - Eduardo Rocon
- Centro de Automática y Robótica, Consejo Superior de Investigaciones Científicas, Arganda del Rey
| | | | - Sergio Lerma Lara
- Laboratorio de Análisis del Movimiento, Hospital Infantil Universitario Niño Jesús
- Facultad de Ciencias de la Salud, CSEU La Salle, Universidad Autónoma de Madrid, Madrid, Spain
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214
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Kaneguchi A, Ozawa J, Moriyama H, Yamaoka K. Nociception contributes to the formation of myogenic contracture in the early phase of adjuvant-induced arthritis in a rat knee. J Orthop Res 2017; 35:1404-1413. [PMID: 27584936 DOI: 10.1002/jor.23412] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 08/25/2016] [Indexed: 02/04/2023]
Abstract
It is unknown how joint contracture is generated in inflamed joints. This study aimed to clarify the role of nociception on the formation of joint contracture secondary to arthritis. Monoarthritis was induced by intra-articular injections of complete Freund's adjuvant (CFA) into rat knees. On day 5 after CFA injection, the passive extension range of motion (ROM) of knee joints were measured, both before and after myotomy of knee flexors, to evaluate the extent of muscular contribution to CFA-induced joint contracture. The steroidal anti-inflammatory drug dexamethasone could prevent ROM restrictions completely, both before and after myotomy. On the other hand, the opioid analgesic drug morphine did not prevent the development of restricted ROM observed after myotomy, while it did before myotomy. This indicates that nociception contributes to joint contracture through alterations in muscular structure (myogenic factors). Next, we tested the hypothesis that nociception-induced reflexive flexor muscle contractions cause myogenic contracture in arthritic joints. To do this, chemical denervation was performed by Botulinum toxin type A (BTX-A) injections into knee flexor muscles, simultaneously with CFA injections into the knee. As expected, BTX-A could alleviate ROM restrictions observed before myotomy. These findings suggest that nociceptive-related muscle contractions play an essential role in the formation of joint contracture. Thus, our study indicates that analgesic management during an early stage of joint arthritis is an essential mean to prevent the formation of joint contracture. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1404-1413, 2017.
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Affiliation(s)
- Akinori Kaneguchi
- Major in Medical Engineering and Technology, Graduate School of Medical Technology and Health Welfare Sciences, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan
| | - Junya Ozawa
- Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan
| | - Hideki Moriyama
- Department of Rehabilitation Science, Graduate School of Health Sciences, Kobe University, Tomogaoka 7-10-2, Suma-ku, Kobe, Hyogo, Japan
| | - Kaoru Yamaoka
- Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan
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215
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Kaneguchi A, Ozawa J, Kawamata S, Yamaoka K. Development of arthrogenic joint contracture as a result of pathological changes in remobilized rat knees. J Orthop Res 2017; 35:1414-1423. [PMID: 27601089 DOI: 10.1002/jor.23419] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 08/31/2016] [Indexed: 02/04/2023]
Abstract
This study aimed to elucidate how rats recover from immobilization-induced knee joint contracture. Rats' right knees were immobilized by an external fixator at a flexion of 140° for 3 weeks. After removal of the fixator, the joints were allowed to move freely (remobilization) for 0, 1, 3, 7, or 14 days (n = 5 each). To distinguish myogenic and arthrogenic contractures, the passive extension range of motion was measured before and after myotomy of the knee flexors. Knee joints were histologically analyzed and the expression of genes encoding inflammatory or fibrosis-related mediators, interleukin-1β (1L-1β), fibrosis-related transforming growth factor-β1 (TGF-β1), and collagen type I (COL1A1) and III (COL3A1), were examined in the knee joint posterior capsules using real-time PCR. Both myogenic and arthrogenic contractures were established within 3 weeks of immobilization. During remobilization, the myogenic contracture decreased over time. In contrast, the arthrogenic contracture developed further during the remobilization period. On day 1 of remobilization, inflammatory changes characterized by edema, inflammatory cell infiltration, and upregulation of IL-1β gene started in the knee joint posterior capsule. In addition, collagen deposition accompanied by fibroblast proliferation, with upregulation of TGF-β1, COL1A1, and COL3A1 genes, appeared in the joint capsule between days 7 and 14. These results suggest the progression of arthrogenic contracture following remobilization, which is characterized by fibrosis development, is possibly triggered by inflammation in the joint capsule. It is therefore necessary to focus on developing new treatment strategies for immobilization-induced joint contracture. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1414-1423, 2017.
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Affiliation(s)
- Akinori Kaneguchi
- Major in Medical Engineering and Technology, Graduate School of Medical Technology and Health Welfare Sciences, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan
| | - Junya Ozawa
- Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima 739-2695, Japan
| | - Seiichi Kawamata
- Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3, Kasumi, Minami-Ku, Hiroshima, Japan
| | - Kaoru Yamaoka
- Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima 739-2695, Japan
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216
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Ward SR, Minamoto VB, Suzuki KP, Hulst JB, Bremner SN, Lieber RL. Recovery of rat muscle size but not function more than 1 year after a single botulinum toxin injection. Muscle Nerve 2017; 57:435-441. [PMID: 28556093 DOI: 10.1002/mus.25707] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 05/22/2017] [Accepted: 05/23/2017] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Neurotoxin injection is used to treat a wide variety of neuromuscular disorders. The purpose of this study was to measure the functional and structural properties of botulinum toxin-injected adult rat skeletal muscle over nearly the entire lifespan. METHODS Ten groups of animals were subjected to either neurotoxin injection [Botox, Type A (BT-A); Allergan, Irvine, California] or saline solution injection. Neurotoxin-injected animals (n = 90) were analyzed at different time-points: 1 week; 1 month; 3 months; 6 months; 12 months; or 18 months. RESULTS In spite of the recovery of structural features, such as muscle mass and fiber area, dorsiflexion torque production remained significantly depressed by 25%, even at 12 months after neurotoxin injection. DISCUSSION The data demonstrate that, after a single BT-A injection, although gross muscle morphology recovered over a 12-month time period, loss of contractile function did not recover. Muscle Nerve 57: 435-441, 2018.
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Affiliation(s)
- Samuel R Ward
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA.,Department of Bioengineering, University of California, San Diego, La Jolla, California, USA.,Department of Radiology, University of California, San Diego, La Jolla, California, USA
| | - Viviane B Minamoto
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA
| | - Kentaro P Suzuki
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA
| | - Jonah B Hulst
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA
| | - Shannon N Bremner
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA
| | - Richard L Lieber
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California, USA.,Department of Bioengineering, University of California, San Diego, La Jolla, California, USA.,Rehabilitation Institute of Chicago, 345 East Superior Street, Chicago, Illinois, 60611, USA
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217
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Wu CH, Ho YC, Hsiao MY, Chen WS, Wang TG. Evaluation of Post-Stroke Spastic Muscle Stiffness Using Shear Wave Ultrasound Elastography. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:1105-1111. [PMID: 28285729 DOI: 10.1016/j.ultrasmedbio.2016.12.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/12/2016] [Accepted: 12/14/2016] [Indexed: 06/06/2023]
Abstract
Current clinical evaluations of post-stroke upper limb spasticity are subjective and qualitative. We proposed a quantitative measurement of post-stroke spastic muscle stiffness by using shear-wave ultrasound elastography and tested its reliability. Acoustic radiation force impulse with shear wave velocity (SWV) detection was used to evaluate stiffness of the biceps brachii muscles at 90° and 0° elbow flexion. In 21 control subjects, SWV did not significantly differ between dominant and non-dominant sides at either flexion angle (0°: p = 0.311, 90°: p = 0.436). In 31 patients who had recent stroke, SWV was significantly greater on the paretic side than on the non-paretic side at both 90° (2.23 ± 0.15 m/s vs. 1.88 ± 0.08 m/s, p = 0.036) and 0° (3.28 ± 0.11 m/s vs. 2.93 ± 0.06 m/s, p = 0.002). The physical appearance of arms and forearms of our patients and controls prevented blinding of the rater to paretic or non-paretic side. At 90°, SWV on the paretic side correlated positively with modified Ashworth scale and modified Tardieu scale (spasticity severity) and negatively with Stroke Rehabilitation Assessment of Movement score (motor function impairment). The intra-class correlation coefficients of intra-rater and inter-rater reliability for SWV measurements were classified as excellent. In conclusion, high SWV was associated with high spasticity and poor function of the post-stroke upper limb, suggesting possible use as a reliable quantitative measure for disease progression and treatment follow-up.
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Affiliation(s)
- Chueh-Hung Wu
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Chun Ho
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Ming-Yen Hsiao
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wen-Shiang Chen
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Tyng-Guey Wang
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
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218
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Resistance to radial expansion limits muscle strain and work. Biomech Model Mechanobiol 2017; 16:1633-1643. [PMID: 28432448 DOI: 10.1007/s10237-017-0909-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 04/07/2017] [Indexed: 10/19/2022]
Abstract
The collagenous extracellular matrix (ECM) of skeletal muscle functions to transmit force, protect sensitive structures, and generate passive tension to resist stretch. The mechanical properties of the ECM change with age, atrophy, and neuromuscular pathologies, resulting in an increase in the relative amount of collagen and an increase in stiffness. Although numerous studies have focused on the effect of muscle fibrosis on passive muscle stiffness, few have examined how these structural changes may compromise contractile performance. Here we combine a mathematical model and experimental manipulations to examine how changes in the mechanical properties of the ECM constrain the ability of muscle fibers and fascicles to radially expand and how such a constraint may limit active muscle shortening. We model the mechanical interaction between a contracting muscle and the ECM using a constant volume, pressurized, fiber-wound cylinder. Our model shows that as the proportion of a muscle cross section made up of ECM increases, the muscle's ability to expand radially is compromised, which in turn restricts muscle shortening. In our experiments, we use a physical constraint placed around the muscle to restrict radial expansion during a contraction. Our experimental results are consistent with model predictions and show that muscles restricted from radial expansion undergo less shortening and generate less mechanical work under identical loads and stimulation conditions. This work highlights the intimate mechanical interaction between contractile and connective tissue structures within skeletal muscle and shows how a deviation from a healthy, well-tuned relationship can compromise performance.
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219
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Zhou J, Butler EE, Rose J. Neurologic Correlates of Gait Abnormalities in Cerebral Palsy: Implications for Treatment. Front Hum Neurosci 2017; 11:103. [PMID: 28367118 PMCID: PMC5355477 DOI: 10.3389/fnhum.2017.00103] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 02/20/2017] [Indexed: 01/17/2023] Open
Abstract
Cerebral palsy (CP) is the most common movement disorder in children. A diagnosis of CP is often made based on abnormal muscle tone or posture, a delay in reaching motor milestones, or the presence of gait abnormalities in young children. Neuroimaging of high-risk neonates and of children diagnosed with CP have identified patterns of neurologic injury associated with CP, however, the neural underpinnings of common gait abnormalities remain largely uncharacterized. Here, we review the nature of the brain injury in CP, as well as the neuromuscular deficits and subsequent gait abnormalities common among children with CP. We first discuss brain injury in terms of mechanism, pattern, and time of injury during the prenatal, perinatal, or postnatal period in preterm and term-born children. Second, we outline neuromuscular deficits of CP with a focus on spastic CP, characterized by muscle weakness, shortened muscle-tendon unit, spasticity, and impaired selective motor control, on both a microscopic and functional level. Third, we examine the influence of neuromuscular deficits on gait abnormalities in CP, while considering emerging information on neural correlates of gait abnormalities and the implications for strategic treatment. This review of the neural basis of gait abnormalities in CP discusses what is known about links between the location and extent of brain injury and the type and severity of CP, in relation to the associated neuromuscular deficits, and subsequent gait abnormalities. Targeted treatment opportunities are identified that may improve functional outcomes for children with CP. By providing this context on the neural basis of gait abnormalities in CP, we hope to highlight areas of further research that can reduce the long-term, debilitating effects of CP.
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Affiliation(s)
- Joanne Zhou
- Department of Orthopaedic Surgery, Stanford UniversityStanford, CA, USA; Motion and Gait Analysis Lab, Lucile Packard Children's HospitalPalo Alto, CA, USA
| | - Erin E Butler
- Thayer School of Engineering, Dartmouth CollegeHanover, NH, USA; Neukom Institute for Computational Sciences, Dartmouth CollegeHanover, NH, USA
| | - Jessica Rose
- Department of Orthopaedic Surgery, Stanford UniversityStanford, CA, USA; Motion and Gait Analysis Lab, Lucile Packard Children's HospitalPalo Alto, CA, USA
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220
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Ceyhan Bilgici M, Bekci T, Ulus Y, Bilgici A, Tomak L, Selcuk MB. Quantitative assessment of muscle stiffness with acoustic radiation force impulse elastography after botulinum toxin A injection in children with cerebral palsy. J Med Ultrason (2001) 2017; 45:137-141. [PMID: 28271231 DOI: 10.1007/s10396-017-0780-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/03/2017] [Indexed: 01/10/2023]
Abstract
PURPOSE Our objective in this study was to assess the changes in medial gastrocnemius muscle (GCM) stiffness after botulinum toxin A (BTA) injection in children with cerebral palsy (CP) by using acoustic radiation force impulse (ARFI) elastography and to research the usability of this technique in clinical practice. MATERIALS AND METHODS Twenty-four spastic lower extremities of 12 children with CP were assessed. BTA injection treatment was applied to the medial GCM. Muscle stiffness was measured with the ARFI technique before the procedure and a month after the procedure. The patients were assessed with the modified Ashworth scale (MAS) in the physiotherapy department at about the same time. Shear wave velocity (SWV) values and MAS scores before and after the treatment were compared. RESULTS Mean SWV values were measured as 3.20 ± 0.14 m/s before BTA and as 2.45 ± 0.21 m/s after BTA, and the difference between them was found to be statistically significant (p < 0.001). Mean MAS score (2.33 ± 0.70) after BTA decreased significantly when compared to the score before BTA (2.96 ± 0.62) (p = 0.001). SWV values positively correlated with MAS scores (ρ = 0.578, p = 0.003). The interobserver agreement expressed as interclass correlation coefficient (ICC) was 0.65 (95% CI 0.33-0.84, p < 0.001). CONCLUSION ARFI elastography for identifying structural changes that occur in the spastic muscle after BTA injection in children with CP can yield more valuable information with combined use of MAS.
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Affiliation(s)
- Meltem Ceyhan Bilgici
- Ondokuz Mayis University Faculty of Medicine, Department of Radiology, Samsun, Turkey
| | - Tumay Bekci
- Zonguldak State Hospital, Radiology Clinic, Zonguldak, Turkey.
| | - Yasemin Ulus
- Ondokuz Mayis University Faculty of Medicine, Department of Physical Therapy and Rehabilitation, Samsun, Turkey
| | - Ayhan Bilgici
- Ondokuz Mayis University Faculty of Medicine, Department of Physical Therapy and Rehabilitation, Samsun, Turkey
| | - Leman Tomak
- Ondokuz Mayis University Faculty of Medicine, Department of Medical Biostatistics, Samsun, Turkey
| | - Mustafa Bekir Selcuk
- Ondokuz Mayis University Faculty of Medicine, Department of Radiology, Samsun, Turkey
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221
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Pingel J, Bartels EM, Nielsen JB. New perspectives on the development of muscle contractures following central motor lesions. J Physiol 2017; 595:1027-1038. [PMID: 27779750 PMCID: PMC5309377 DOI: 10.1113/jp272767] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 10/18/2016] [Indexed: 01/03/2023] Open
Abstract
Muscle contractures are common in patients with central motor lesions, but the mechanisms responsible for the development of contractures are still unclear. Increased or decreased neural activation, protracted placement of a joint with the muscle in a short position and muscle atrophy have been suggested to be involved, but none of these mechanisms are sufficient to explain the development of muscle contractures alone. Here we propose that changes in tissue homeostasis in the neuromuscular-tendon-connective tissue complex is at the heart of the development of contractures, and that an integrated physiological understanding of the interaction between neural, mechanical and metabolic factors, as well as genetic and epigenetic factors, is necessary in order to unravel the mechanisms that result in muscle contractures. We hope thereby to contribute to a reconsideration of how and why muscle contractures develop in a way which will open a window towards new insight in this area in the future.
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Affiliation(s)
- J. Pingel
- Department of ExerciseNutrition and SportsUniversity of CopenhagenDenmark
| | - E. M. Bartels
- The Biochemistry and Physiology LaboratoryThe Parker InstituteCopenhagen University HospitalBispebjerg and FrederiksbergDenmark
| | - J. B. Nielsen
- Department of ExerciseNutrition and SportsUniversity of CopenhagenDenmark
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222
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Neyroud D, Armand S, De Coulon G, Maffiuletti NA, Kayser B, Place N. Plantar flexor muscle weakness and fatigue in spastic cerebral palsy patients. RESEARCH IN DEVELOPMENTAL DISABILITIES 2017; 61:66-76. [PMID: 28064025 DOI: 10.1016/j.ridd.2016.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Patients with cerebral palsy develop an important muscle weakness which might affect the aetiology and extent of exercise-induced neuromuscular fatigue. AIM This study evaluated the aetiology and extent of plantar flexor neuromuscular fatigue in patients with cerebral palsy. METHODS Ten patients with cerebral palsy and 10 age- and sex-matched healthy individuals (∼20 years old, 6 females) performed four 30-s maximal isometric plantar flexions interspaced by a resting period of 2-3s to elicit a resting twitch. Maximal voluntary contraction force, voluntary activation level and peak twitch were quantified before and immediately after the fatiguing task. RESULTS Before fatigue, patients with cerebral palsy were weaker than healthy individuals (341±134N vs. 858±151N, p<0.05) and presented lower voluntary activation (73±19% vs. 90±9%, p<0.05) and peak twitch (100±28N vs. 199±33N, p<0.05). Maximal voluntary contraction force was not significantly reduced in patients with cerebral palsy following the fatiguing task (-10±23%, p>0.05), whereas it decreased by 30±12% (p<0.05) in healthy individuals. CONCLUSIONS Plantar flexor muscles of patients with cerebral palsy were weaker than their healthy peers but showed greater fatigue resistance. WHAT THIS PAPER ADDS Cerebral palsy is a widely defined pathology that is known to result in muscle weakness. The extent and origin of muscle weakness were the topic of several previous investigations; however some discrepant results were reported in the literature regarding how it might affect the development of exercise-induced neuromuscular fatigue. Importantly, most of the studies interested in the assessment of fatigue in patients with cerebral palsy did so with general questionnaires and reported increased levels of fatigue. Yet, exercise-induced neuromuscular fatigue was quantified in just a few studies and it was found that young patients with cerebral palsy might be more fatigue resistant that their peers. Thus, it appears that (i) conflicting results exist regarding objectively-evaluated fatigue in patients with cerebral palsy and (ii) the mechanisms underlying this muscle fatigue - in comparison to those of healthy peers - remain poorly understood. The present study adds important knowledge to the field as it shows that when young adults with cerebral palsy perform sustained maximal isometric plantar flexions, they appear less fatigable than healthy peers. This difference can be ascribed to a better preservation of the neural drive to the muscle. We suggest that the inability to drive their muscles maximally accounts for the lower extent of exercise-induced neuromuscular fatigue in patients with cerebral palsy.
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Affiliation(s)
- Daria Neyroud
- Institute of Sport Sciences, Faculty of Biology Medicine, University of Lausanne, Lausanne, Switzerland; Institute of Movement Sciences and Sports Medicine, University of Geneva, Geneva, Switzerland
| | - Stéphane Armand
- Willy Taillard Laboratory of Kinesiology, Geneva University Hospitals and Geneva University, Switzerland
| | - Geraldo De Coulon
- Service of Pediatric Orthopaedics, Department of Child and Adolescent Health, Geneva University Hospitals and Geneva University, Geneva, Switzerland
| | | | - Bengt Kayser
- Institute of Sport Sciences, Faculty of Biology Medicine, University of Lausanne, Lausanne, Switzerland; Institute of Movement Sciences and Sports Medicine, University of Geneva, Geneva, Switzerland
| | - Nicolas Place
- Institute of Sport Sciences, Faculty of Biology Medicine, University of Lausanne, Lausanne, Switzerland.
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223
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Chapman MA, Mukund K, Subramaniam S, Brenner D, Lieber RL. Three distinct cell populations express extracellular matrix proteins and increase in number during skeletal muscle fibrosis. Am J Physiol Cell Physiol 2017; 312:C131-C143. [PMID: 27881411 PMCID: PMC5336596 DOI: 10.1152/ajpcell.00226.2016] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 11/15/2016] [Accepted: 11/15/2016] [Indexed: 02/06/2023]
Abstract
Tissue extracellular matrix (ECM) provides structural support and creates unique environments for resident cells (Bateman JF, Boot-Handford RP, Lamandé SR. Nat Rev Genet 10: 173-183, 2009; Kjaer M. Physiol Rev 84: 649-98, 2004). However, the identities of cells responsible for creating specific ECM components have not been determined. In striated muscle, the identity of these cells becomes important in disease when ECM changes result in fibrosis and subsequent increased tissue stiffness and dysfunction. Here we describe a novel approach to isolate and identify cells that maintain the ECM in both healthy and fibrotic muscle. Using a collagen I reporter mouse, we show that there are three distinct cell populations that express collagen I in both healthy and fibrotic skeletal muscle. Interestingly, the number of collagen I-expressing cells in all three cell populations increases proportionally in fibrotic muscle, indicating that all cell types participate in the fibrosis process. Furthermore, while some profibrotic ECM and ECM-associated genes are significantly upregulated in fibrotic muscle, the fibrillar collagen gene expression profile is not qualitatively altered. This suggests that muscle fibrosis in this model results from an increased number of collagen I-expressing cells and not the initiation of a specific fibrotic collagen gene expression program. Finally, in fibrotic muscle, we show that these collagen I-expressing cell populations differentially express distinct ECM proteins-fibroblasts express the fibrillar components of ECM, fibro/adipogenic progenitors cells differentially express basal laminar proteins, and skeletal muscle progenitor cells differentially express genes important for the satellite cell.
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Affiliation(s)
- Mark A Chapman
- Department of Bioengineering, University of California San Diego, La Jolla, California
| | - Kavitha Mukund
- Department of Bioengineering, University of California San Diego, La Jolla, California
| | - Shankar Subramaniam
- Department of Bioengineering, University of California San Diego, La Jolla, California
| | - David Brenner
- Department of Medicine, University of California San Diego, La Jolla, California
| | - Richard L Lieber
- Department of Bioengineering, University of California San Diego, La Jolla, California;
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, California
- Department of Veteran's Affairs, La Jolla, California; and
- Rehabilitation Institute of Chicago, Chicago, Illinois
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224
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Sartori M, Fernandez JW, Modenese L, Carty CP, Barber LA, Oberhofer K, Zhang J, Handsfield GG, Stott NS, Besier TF, Farina D, Lloyd DG. Toward modeling locomotion using electromyography-informed 3D models: application to cerebral palsy. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2016; 9. [DOI: 10.1002/wsbm.1368] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 10/11/2016] [Accepted: 10/18/2016] [Indexed: 01/17/2023]
Affiliation(s)
- M. Sartori
- Department of Trauma Surgery; Orthopedics and Plastic Surgery, Neurorehabilitation Systems Research Group, University Medical Center Göttingen; Göttingen Germany
| | - J. W. Fernandez
- Auckland Bioengineering Institute; University of Auckland; Auckland New Zealand
- Department of Engineering Science; University of Auckland; Auckland New Zealand
| | - L. Modenese
- Department of Mechanical Engineering; The University of Sheffield; Sheffield UK
- Queensland Children's Motion Analysis Service, Queensland Paediatric Rehabilitation Service; Children's Health Queensland; Brisbane Australia
- Menzies Health Institute Queensland; Griffith University; Queensland Australia
| | - C. P. Carty
- Queensland Children's Motion Analysis Service, Queensland Paediatric Rehabilitation Service; Children's Health Queensland; Brisbane Australia
- Menzies Health Institute Queensland; Griffith University; Queensland Australia
- School of Allied Health Sciences; Griffith University; Queensland Australia
| | - L. A. Barber
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine; The University of Queensland; Brisbane Australia
| | - K. Oberhofer
- Auckland Bioengineering Institute; University of Auckland; Auckland New Zealand
| | - J. Zhang
- Auckland Bioengineering Institute; University of Auckland; Auckland New Zealand
| | - G. G. Handsfield
- Auckland Bioengineering Institute; University of Auckland; Auckland New Zealand
| | - N. S. Stott
- School of Medicine; University of Auckland; Auckland New Zealand
| | - T. F. Besier
- Auckland Bioengineering Institute; University of Auckland; Auckland New Zealand
- Department of Engineering Science; University of Auckland; Auckland New Zealand
| | - D. Farina
- Department of Bioengineering; Imperial College London; London UK
| | - D. G. Lloyd
- Menzies Health Institute Queensland; Griffith University; Queensland Australia
- School of Allied Health Sciences; Griffith University; Queensland Australia
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225
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Gillies AR, Chapman MA, Bushong EA, Deerinck TJ, Ellisman MH, Lieber RL. High resolution three-dimensional reconstruction of fibrotic skeletal muscle extracellular matrix. J Physiol 2016; 595:1159-1171. [PMID: 27859324 DOI: 10.1113/jp273376] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 10/24/2016] [Indexed: 01/18/2023] Open
Abstract
KEY POINTS Fibrosis occurs secondary to many skeletal muscle diseases and injuries, and can alter muscle function. It is unknown how collagen, the most abundant extracellular structural protein, alters its organization during fibrosis. Quantitative and qualitative high-magnification electron microscopy shows that collagen is organized into perimysial cables which increase in number in a model of fibrosis, and cables have unique interactions with collagen-producing cells. Fibrotic muscles are stiffer and have a higher concentration of collagen-producing cells. These results improve our understanding of the organization of fibrotic skeletal muscle extracellular matrix and identify novel structures that might be targeted by antifibrotic therapy. ABSTRACT Skeletal muscle extracellular matrix (ECM) structure and organization are not well understood, yet the ECM plays an important role in normal tissue homeostasis and disease processes. Fibrosis is common to many muscle diseases and is typically quantified based on an increase in ECM collagen. Through the use of multiple imaging modalities and quantitative stereology, we describe the structure and composition of wild-type and fibrotic ECM, we show that collagen in the ECM is organized into large bundles of fibrils, or collagen cables, and the number of these cables (but not their size) increases in desmin knockout muscle (a fibrosis model). The increase in cable number is accompanied by increased muscle stiffness and an increase in the number of collagen producing cells. Unique interactions between ECM cells and collagen cables were also observed and reconstructed by serial block face scanning electron microscopy. These results demonstrate that the muscle ECM is more highly organized than previously reported. Therapeutic strategies for skeletal muscle fibrosis should consider the organization of the ECM to target the structures and cells contributing to fibrotic muscle function.
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Affiliation(s)
- Allison R Gillies
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Mark A Chapman
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA.,Karolinska Institute, Stockholm, Sweden
| | - Eric A Bushong
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, CA, 92093, USA
| | - Thomas J Deerinck
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, CA, 92093, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, CA, 92093, USA.,Department of Neurosciences, University of California San Diego, La Jolla, CA, 92093, USA
| | - Richard L Lieber
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA.,Department of Orthopaedic Surgery, University of California San Diego, La Jolla, CA, 92093, USA.,Rehabilitation Institute of Chicago, Chicago, IL, 60611, USA
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226
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Brandenburg JE, Eby SF, Song P, Kingsley-Berg S, Bamlet W, Sieck GC, An KN. Quantifying passive muscle stiffness in children with and without cerebral palsy using ultrasound shear wave elastography. Dev Med Child Neurol 2016; 58:1288-1294. [PMID: 27374483 PMCID: PMC5118061 DOI: 10.1111/dmcn.13179] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/01/2016] [Indexed: 01/02/2023]
Abstract
AIM The aim of this study was to compare passive muscle stiffness in children with cerebral palsy (CP) and children with typical development using a novel ultrasound technique: ultrasound shear wave elastography (SWE). METHOD We conducted a prospective study of 13 children with CP (six females and seven males, median age 5y 1mo [interquartile range 4y 4mo-7y 8mo]) and 13 children with typical development (six females and seven males, median age 5y 3mo [interquartile range 4y 4mo-9y 4mo]). Demographic information and physical exam measurements were obtained in addition to shear modulus measurements (passive muscle stiffness) of the lateral gastrocnemius muscle at 20° plantar flexion, 10° plantar flexion, and 0° plantar flexion using SWE. RESULTS Children with CP had significantly greater shear modulus measurements at all three foot positions (p<0.050). When the shear modulus values were normalized to the baseline value for each child, there was no significant difference between the two groups. INTERPRETATION Passive muscle stiffness, measured without the influence of spasticity, is greater in children with CP than in children with typical development when a muscle is at slack and at stretch. When shear modulus was normalized, the results indicate that muscle in children in both groups responds similarly to passive stretch. Further work includes evaluating effect of botulinum toxin on passive muscle properties.
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Affiliation(s)
- Joline E. Brandenburg
- Department of Physical Medicine and Rehabilitation,Department of Neurology,Department of Pediatric and Adolescent Medicine
| | - Sarah F. Eby
- Mayo Graduate School, Medical Scientist Training Program, Mayo Clinic College of Medicine Mayo Clinic, Rochester, MN
| | | | | | | | | | - Kai-Nan An
- Department of Physiology and Biomedical Engineering,Division of Orthopedic Research
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227
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Kinney MC, Dayanidhi S, Dykstra PB, McCarthy JJ, Peterson CA, Lieber RL. Reduced skeletal muscle satellite cell number alters muscle morphology after chronic stretch but allows limited serial sarcomere addition. Muscle Nerve 2016; 55:384-392. [PMID: 27343167 DOI: 10.1002/mus.25227] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/14/2016] [Accepted: 06/16/2016] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Muscles add sarcomeres in response to stretch, presumably to maintain optimal sarcomere length. Clinical evidence from patients with cerebral palsy, who have both decreased serial sarcomere number and reduced satellite cells (SCs), suggests a hypothesis that SCs may be involved in sarcomere addition. METHODS A transgenic Pax7-DTA mouse model underwent conditional SC depletion, and their soleii were then stretch-immobilized to assess the capacity for sarcomere addition. Muscle architecture, morphology, and extracellular matrix (ECM) changes were also evaluated. RESULTS Mice in the SC-reduced group achieved normal serial sarcomere addition in response to stretch. However, muscle fiber cross-sectional area was significantly smaller and was associated with hypertrophic ECM changes, consistent with fibrosis. CONCLUSIONS While a reduced SC population does not hinder serial sarcomere addition, SCs play a role in muscle adaptation to chronic stretch that involves maintenance of both fiber cross-sectional area and ECM structure. Muscle Nerve 55: 384-392, 2017.
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Affiliation(s)
- Matthew C Kinney
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA
| | - Sudarshan Dayanidhi
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Department of Veterans Affairs Medical Center, San Diego, California, USA
| | - Peter B Dykstra
- Department of Bioengineering, University of California, San Diego, California, USA
| | - John J McCarthy
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Charlotte A Peterson
- Department of Rehabilitation Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Richard L Lieber
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Department of Veterans Affairs Medical Center, San Diego, California, USA.,Department of Bioengineering, University of California, San Diego, California, USA
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228
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Spyrou LA, Agoras M, Danas K. A homogenization model of the Voigt type for skeletal muscle. J Theor Biol 2016; 414:50-61. [PMID: 27884495 DOI: 10.1016/j.jtbi.2016.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/12/2016] [Accepted: 11/18/2016] [Indexed: 10/20/2022]
Abstract
A three-dimensional constitutive model for skeletal muscle incorporating microstructural characteristics is developed and numerically implemented in a general purpose finite element program. The proposed model takes into account explicitly the volume fractions of muscle fibers and connective tissue by using the Voigt homogenization approach to bridge the different length scales of the muscle structure. The model is used to estimate the active and passive homogenized muscle response. Next, the model is validated by experimental data and periodic three-dimensional unit cell calculations comprising various fiber volume fractions and mechanical properties of the constituents. The model is found to be in very good agreement with both the experimental data and the finite element results for all the examined cases. The influence of fiber volume fraction and material properties of constituents on effective muscle response under several loading conditions is examined.
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Affiliation(s)
- L A Spyrou
- Institute for Research & Technology - Thessaly, Centre for Research & Technology Hellas (CERTH), 38333 Volos, Greece.
| | - M Agoras
- Department of Mechanical Engineering, University of Thessaly, 38334 Volos, Greece.
| | - K Danas
- LMS, CNRS, École Polytechnique, Université Paris-Saclay, 91128 Palaiseau, France.
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229
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Hussain AW, Onambélé GL, Williams AG, Morse CI. Medial gastrocnemius specific force of adult men with spastic cerebral palsy. Muscle Nerve 2016; 56:298-306. [PMID: 27862024 PMCID: PMC5573928 DOI: 10.1002/mus.25477] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 11/02/2016] [Accepted: 11/11/2016] [Indexed: 12/05/2022]
Abstract
Introduction: Muscle weakness determines functional impairment in spastic cerebral palsy (SCP). Measurement of specific force (SF) allows for strength comparison with unimpaired populations (controls) accounting for neural (activation and coactivation), architectural (fascicle length and pennation angle), and structural differences (moment arm length). Methods: Medial gastrocnemius (MG) SF (and its determinants) was assessed in both paretic and non‐paretic legs of 11 men with SCP and 11 age‐matched controls during plantarflexion maximal voluntary isometric contraction (MVIC). Results: SCP fascicles were 28% longer than control fascicles (P < 0.05). Pennation angle of SCP patients was 41% smaller than in controls. The physiological cross‐sectional area of SCP MG patients was 47% smaller than in controls (P < 0.05). There was no difference in SF between controls and SCP patients. Conclusions: Weakness in SCP is primarily attributable to deficits in agonist activation and muscle size; consequently, SF measured in the MG is similar between SCP and controls. Muscle Nerve56: 298–306, 2017
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Affiliation(s)
- Ayser W Hussain
- Health Exercise and Active Living Research Centre, Department of Exercise and Sport Science, Manchester Metropolitan University, Crewe Green Road, Cheshire, CW1 5DU, UK
| | - Gladys L Onambélé
- Health Exercise and Active Living Research Centre, Department of Exercise and Sport Science, Manchester Metropolitan University, Crewe Green Road, Cheshire, CW1 5DU, UK
| | - Alun G Williams
- Health Exercise and Active Living Research Centre, Department of Exercise and Sport Science, Manchester Metropolitan University, Crewe Green Road, Cheshire, CW1 5DU, UK
| | - Christopher I Morse
- Health Exercise and Active Living Research Centre, Department of Exercise and Sport Science, Manchester Metropolitan University, Crewe Green Road, Cheshire, CW1 5DU, UK
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230
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Haberfehlner H, Jaspers RT, Rutz E, Becher JG, Harlaar J, van der Sluijs JA, Witbreuk MM, Romkes J, Freslier M, Brunner R, Maas H, Buizer AI. Knee Moment-Angle Characteristics and Semitendinosus Muscle Morphology in Children with Spastic Paresis Selected for Medial Hamstring Lengthening. PLoS One 2016; 11:e0166401. [PMID: 27861523 PMCID: PMC5115739 DOI: 10.1371/journal.pone.0166401] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 10/30/2016] [Indexed: 11/18/2022] Open
Abstract
To increase knee range of motion and improve gait in children with spastic paresis (SP), the semitendinosus muscle (ST) amongst other hamstring muscles is frequently lengthened by surgery, but with variable success. Little is known about how the pre-surgical mechanical and morphological characteristics of ST muscle differ between children with SP and typically developing children (TD). The aims of this study were to assess (1) how knee moment-angle characteristics and ST morphology in children with SP selected for medial hamstring lengthening differ from TD children, as well as (2) how knee moment-angle characteristics and ST morphology are related. In nine SP and nine TD children, passive knee moment-angle characteristics and morphology of ST (i.e. fascicle length, muscle belly length, tendon length, physiological cross-sectional area, and volume) were assessed by hand-held dynamometry and freehand 3D ultrasound, respectively. At net knee flexion moments above 0.5 Nm, more flexed knee angles were found for SP compared to TD children. The measured knee angle range between 0 and 4 Nm was 30% smaller in children with SP. Muscle volume, physiological cross-sectional area, and fascicle length normalized to femur length were smaller in SP compared to TD children (62%, 48%, and 18%, respectively). Sixty percent of the variation in knee angles at 4 Nm net knee moment was explained by ST fascicle length. Altered knee moment-angle characteristics indicate an increased ST stiffness in SP children. Morphological observations indicate that in SP children planned for medial hamstring lengthening, the longitudinal and cross-sectional growth of ST muscle fibers is reduced. The reduced fascicle length can partly explain the increased ST stiffness and, hence, a more flexed knee joint in these SP children.
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Affiliation(s)
- Helga Haberfehlner
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands
- Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
| | - Richard T. Jaspers
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
- * E-mail:
| | - Erich Rutz
- Pediatric Orthopaedic Department, University Children’s Hospital Basle (UKBB), Basle, Switzerland
- Laboratory for Movement Analysis, University Children's Hospital Basle (UKBB), Basle, Switzerland
| | - Jules G. Becher
- Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
| | - Jaap Harlaar
- Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
| | - Johannes A. van der Sluijs
- MOVE Research Institute Amsterdam, The Netherlands
- Department of Orthopaedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
| | - Melinda M. Witbreuk
- MOVE Research Institute Amsterdam, The Netherlands
- Department of Orthopaedic Surgery, VU University Medical Center, Amsterdam, The Netherlands
| | - Jacqueline Romkes
- Laboratory for Movement Analysis, University Children's Hospital Basle (UKBB), Basle, Switzerland
| | - Marie Freslier
- Laboratory for Movement Analysis, University Children's Hospital Basle (UKBB), Basle, Switzerland
| | - Reinald Brunner
- Pediatric Orthopaedic Department, University Children’s Hospital Basle (UKBB), Basle, Switzerland
- Laboratory for Movement Analysis, University Children's Hospital Basle (UKBB), Basle, Switzerland
| | - Huub Maas
- Laboratory for Myology, Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
| | - Annemieke I. Buizer
- Department of Rehabilitation Medicine, VU University Medical Center, Amsterdam, The Netherlands
- MOVE Research Institute Amsterdam, The Netherlands
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231
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Barber LA, Read F, Lovatt Stern J, Lichtwark G, Boyd RN. Medial gastrocnemius muscle volume in ambulant children with unilateral and bilateral cerebral palsy aged 2 to 9 years. Dev Med Child Neurol 2016; 58:1146-1152. [PMID: 27098082 DOI: 10.1111/dmcn.13132] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/25/2016] [Indexed: 12/23/2022]
Abstract
AIM Calf muscle growth in children with unilateral cerebral palsy (UCP) and bilateral cerebral palsy (BCP) is unknown. This cross-sectional study examines the medial gastrocnemius growth rates of ambulatory children with UCP and BCP compared with children with typical development (CTD), aged 2 to 9 years. METHOD Fifty children with UCP (mean age 66mo [SD 18], 29 males, Gross Motor Function Classification System [GMFCS] I=32, II=18), 50 children with BCP (age 64mo [SD 19], 31 males, GMFCS I=21, II=29), and 78 CTD (age 64mo [SD 16], 40 males) participated in the study. The medial gastrocnemius muscle volume was measured at rest using a validated freehand three-dimensional (3D) ultrasound method. RESULTS Normalized medial gastrocnemius muscle growth rate was significantly less in the children with UCP (0.001 mL/kg/mo) compared with the BCP (0.015 mL/kg/mo, p=0.001) and CTD (0.014 mL/kg/mo, p<0.001) groups. Normalized medial gastrocnemius muscle growth rate was the same in the BCP and CTD groups (p=0.77). INTERPRETATION The normalized growth rate of the medial gastrocnemius muscle in children aged 2 to 9 years with UCP is significantly lower compared with children with BCP and CTD. The growth rate differences in the children with UCP compared with BCP raises questions about the underlying mechanisms that lead to reduced growth in each cerebral palsy (CP) group and potential differences in muscle recovery response in UCP and BCP following treatment.
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Affiliation(s)
- Lee A Barber
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, The University of Queensland, South Brisbane, Qld, Australia.
| | - Felicity Read
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, The University of Queensland, South Brisbane, Qld, Australia
| | - Jacquie Lovatt Stern
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, The University of Queensland, South Brisbane, Qld, Australia
| | - Glen Lichtwark
- School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Qld, Australia
| | - Roslyn N Boyd
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, The University of Queensland, South Brisbane, Qld, Australia
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232
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Scheer NA, Alstat LR, Van Zant RS. Astym Therapy Improves Bilateral Hamstring Flexibility and Achilles Tendinopathy in a Child with Cerebral Palsy: A Retrospective Case Report. CLINICAL MEDICINE INSIGHTS-CASE REPORTS 2016; 9:95-98. [PMID: 27790051 PMCID: PMC5074579 DOI: 10.4137/ccrep.s40623] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 08/23/2016] [Accepted: 08/29/2016] [Indexed: 12/05/2022]
Abstract
PURPOSE The purpose of this case report was to describe the use of Astym therapy to improve hamstring flexibility and Achilles tendinopathy in a child with cerebral palsy. CASE DESCRIPTION An eight-year-old female with cerebral palsy was referred to physical therapy for the treatment of bilateral hamstring inflexibility and Achilles tendinopathy. Treatment focused on an Astym therapy protocol of eccentric exercise, stretching, active and passive range of motion, gait training, and a home exercise program. The patient underwent a total of 11 physical therapy treatment sessions. OUTCOMES At the conclusion of treatment, the patient demonstrated improved resting muscle tone in bilateral lower extremities with active 90/90 hamstring flexibility measured at 165° and ankle dorsiflexion active range of motion of 5° without pain at 0° and 90° knee flexion. The patient exhibited an improved gait pattern with even stride length and diminished genu recurvatum, decreased pain with standing and walking, discontinued use of ankle–foot orthoses, and improved activity tolerance and overall function for daily activities. DISCUSSION The results of this case report indicate that physical therapy rehabilitation utilizing an Astym therapy protocol can successfully achieve gains in flexibility and strength and allow for improved function of bilateral lower extremities in a patient with cerebral palsy. CONCLUSION Based on the findings of this case report, clinicians should consider the use of Astym therapy in treating musculoskeletal soft tissue dysfunction in pediatric patients with cerebral palsy.
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Affiliation(s)
- Nicole A Scheer
- Physical Therapy Program, The University of Findlay, Findlay, OH, USA
| | | | - Robert S Van Zant
- Physical Therapy Program, The University of Findlay, Findlay, OH, USA
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233
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Marsico P, Tal-Akabi A, van Hedel HJA. The relevance of nerve mobility on function and activity in children with Cerebral Palsy. BMC Neurol 2016; 16:194. [PMID: 27717320 PMCID: PMC5054625 DOI: 10.1186/s12883-016-0715-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 09/30/2016] [Indexed: 11/10/2022] Open
Abstract
Background In children with cerebral palsy (CP), stiffness, caused by contractile and non-contractile structures, can influence motor performance. This study sought to determine whether the nerve mobility had a relevant impact on motor performance in children with CP. We hypothesized that a positive Straight Leg Raise (SLR) test, as well as smaller SLR hip angle, would relate to lower leg muscle strength, reduced motor capacity and less motor performance in children with CP. Methods We applied a cross-sectional analysis on data including SLR, leg muscle strength, Gross Motor Function Measure (GMFM-66) and number of activity counts during daily life from thirty children with CP (6–18 years). We performed receiver operating characteristics and correlation analyses. Results Positive SLR test could distinguish well between children with low versus high muscle strength and GMFM-66 scores. The SLR hip angle correlated significant with the level of disability and with muscle strength. The correlation with the GMFM-66 and the activity counts was fair. Conclusion This study suggests that neural restriction of SLR is higher on functional and activity outcome than the measured SLR hip range of motion. Further studies should investigate weather improving nerve mobility can lead to an amelioration of function in children with CP.
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Affiliation(s)
- Petra Marsico
- Paediatric Rehab Research Group, Rehabilitation Centre for Children and Adolescents, University Children's Hospital Zurich, Mühlebergstrasse 104, CH-8910, Affoltern am Albis, Switzerland. .,Children's Research Centre (CRC), University Children's Hospital Zurich, Steinwiessstrasse 75, CH-8032, Zürich, Switzerland.
| | - Amir Tal-Akabi
- Bern University of Applied Sciences, Health, Murtenstrasse 10, CH-3008, Bern, Switzerland
| | - Hubertus J A van Hedel
- Paediatric Rehab Research Group, Rehabilitation Centre for Children and Adolescents, University Children's Hospital Zurich, Mühlebergstrasse 104, CH-8910, Affoltern am Albis, Switzerland.,Children's Research Centre (CRC), University Children's Hospital Zurich, Steinwiessstrasse 75, CH-8032, Zürich, Switzerland
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234
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Zogby AM, Dayanidhi S, Chambers HG, Schenk S, Lieber RL. Skeletal muscle fiber-type specific succinate dehydrogenase activity in cerebral palsy. Muscle Nerve 2016; 55:122-124. [PMID: 27515237 DOI: 10.1002/mus.25379] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2016] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Children with cerebral palsy (CP) exhibit increased energy expenditure during movement, but whether this is due in part to decrements in skeletal muscle mitochondrial oxidative capacity is unknown. Accordingly, we compared fiber-type specific succinate dehydrogenase (SDH) activity in children with CP with typically developing (TD) children. METHODS SDH activity and myofiber areas of type 1 and 2A fibers were measured in semitendinosus biopsies of both groups (n = 5/group). RESULTS SDH activity was ∼35% higher in type 1 compared with type 2A fibers, but there were no differences between groups. Average myofiber area was 45% smaller in CP versus TD (P < 0.05), and type 2A fibers were 32% larger than type 1 fibers (P < 0.05) only in TD children. CONCLUSIONS Fiber-type specific SDH activity is similar between TD children and children with CP. This suggests that increased energy expenditure in children with CP is not related to impaired mitochondrial oxidative capacity. Muscle Nerve, 2016 Muscle Nerve 55: 122-124, 2017.
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Affiliation(s)
- Andrew M Zogby
- School of Medicine, University of California, San Diego, California, USA
| | - Sudarshan Dayanidhi
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Department of Veterans Affairs Medical Center, San Diego, California, USA
| | - Henry G Chambers
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Department of Orthopaedics, Rady Children's Hospital, San Diego, California, USA
| | - Simon Schenk
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Biomedical Sciences Program, University of California, San Diego, California, USA
| | - Richard L Lieber
- Department of Orthopaedic Surgery, University of California, San Diego, California, USA.,Department of Veterans Affairs Medical Center, San Diego, California, USA.,Department of Bioengineering, University of California, San Diego, California, USA
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235
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Pingel J, Wienecke J, Lorentzen J, Nielsen JB. Botulinum toxin injection causes hyper-reflexia and increased muscle stiffness of the triceps surae muscle in the rat. J Neurophysiol 2016; 116:2615-2623. [PMID: 27628204 DOI: 10.1152/jn.00452.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/13/2016] [Indexed: 12/17/2022] Open
Abstract
Botulinum toxin is used with the intention of diminishing spasticity and reducing the risk of development of contractures. Here, we investigated changes in muscle stiffness caused by reflex activity or elastic muscle properties following botulinum toxin injection in the triceps surae muscle in rats. Forty-four rats received injection of botulinum toxin in the left triceps surae muscle. Control measurements were performed on the noninjected contralateral side in all rats. Acute experiments were performed, 1, 2, 4, and 8 wk following injection. The triceps surae muscle was dissected free, and the Achilles tendon was cut and attached to a muscle puller. The resistance of the muscle to stretches of different amplitudes and velocities was systematically investigated. Reflex-mediated torque was normalized to the maximal muscle force evoked by supramaximal stimulation of the tibial nerve. Botulinum toxin injection caused severe atrophy of the triceps surae muscle at all time points. The force generated by stretch reflex activity was also strongly diminished but not to the same extent as the maximal muscle force at 2 and 4 wk, signifying a relative reflex hyperexcitability. Passive muscle stiffness was unaltered at 1 wk but increased at 2, 4, and 8 wk (P < 0.01). These data demonstrate that botulinum toxin causes a relative increase in reflex stiffness, which is likely caused by compensatory neuroplastic changes. The stiffness of elastic elements in the muscles also increased. The data are not consistent with the ideas that botulinum toxin is an efficient antispastic medication or that it may prevent development of contractures.
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Affiliation(s)
- Jessica Pingel
- Neural Control of Movement Research Group, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jacob Wienecke
- Department of Nutrition, Exercise and Sport, University of Copenhagen, Copenhagen, Denmark; and
| | - Jakob Lorentzen
- Neural Control of Movement Research Group, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Elsass Institute, Charlottenlund, Denmark
| | - Jens Bo Nielsen
- Neural Control of Movement Research Group, Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark; .,Elsass Institute, Charlottenlund, Denmark
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236
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Mechanical and material properties of the plantarflexor muscles and Achilles tendon in children with spastic cerebral palsy and typically developing children. J Biomech 2016; 49:3004-3008. [DOI: 10.1016/j.jbiomech.2016.07.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 07/20/2016] [Accepted: 07/20/2016] [Indexed: 11/18/2022]
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237
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Gillett JG, Boyd RN, Carty CP, Barber LA. The impact of strength training on skeletal muscle morphology and architecture in children and adolescents with spastic cerebral palsy: A systematic review. RESEARCH IN DEVELOPMENTAL DISABILITIES 2016; 56:183-196. [PMID: 27337690 DOI: 10.1016/j.ridd.2016.06.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 04/27/2016] [Accepted: 06/03/2016] [Indexed: 06/06/2023]
Abstract
AIM The aim of this study was to systematically review the current literature to determine the impact of strength training on skeletal muscle morphology and architecture in individuals aged 4-20 years with spastic type cerebral palsy. METHODS A comprehensive search for randomised and non-randomised controlled trials, cohort studies and cross-comparison trials was performed on five electronic databases. Included studies were graded according to level of evidence and assessed for methodological quality using the Downs and Black scale. Quantitative data was analysed using effect sizes. RESULTS Six of 304 articles met the inclusion criteria. Methodological quality of the included papers ranged from 14 to 19 (out of 32). A large effect was found on muscle cross-sectional area following strength training, with small to moderate effects on muscle volume and thickness. CONCLUSION AND IMPLICATIONS There is preliminary evidence that strength training leads to hypertrophy in children and adolescents with CP. A paucity of studies exist measuring morphological and architectural parameters following strength training in these individuals. Overall low study methodological quality along with heterogeneous study design, dissimilar outcome measures, and lack of adequate control groups, indicated that care is needed when interpreting the results of these studies in isolation.
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Affiliation(s)
- Jarred G Gillett
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, South Brisbane, Queensland, Australia.
| | - Roslyn N Boyd
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, South Brisbane, Queensland, Australia
| | - Christopher P Carty
- Queensland Children's Motion Analysis Service, Centre for Children's Health Research, Children's Health Queensland Hospital and Health Service, South Brisbane, Queensland, Australia; Centre for Musculoskeletal Research, Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Lee A Barber
- Queensland Cerebral Palsy and Rehabilitation Research Centre, Child Health Research Centre, Faculty of Medicine and Biomedical Sciences, The University of Queensland, South Brisbane, Queensland, Australia
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238
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Eldridge F, Lavin N. How effective is stretching in maintaining range of movement for children with cerebral palsy? A critical review. INTERNATIONAL JOURNAL OF THERAPY AND REHABILITATION 2016. [DOI: 10.12968/ijtr.2016.23.8.386] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Fleur Eldridge
- Graduate physiotherapist, University of Bradford, Bradford, UK
| | - Nicole Lavin
- Physiotherapy lecturer, Division of Allied Health Professions and Sport, Faculty of Health Studies, University of Bradford, Bradford, UK
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239
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Alperin M, Kaddis T, Pichika R, Esparza MC, Lieber RL. Pregnancy-induced adaptations in intramuscular extracellular matrix of rat pelvic floor muscles. Am J Obstet Gynecol 2016; 215:210.e1-7. [PMID: 26875952 DOI: 10.1016/j.ajog.2016.02.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/12/2016] [Accepted: 02/05/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND Birth trauma to pelvic floor muscles is a major risk factor for pelvic floor disorders. Intramuscular extracellular matrix determines muscle stiffness, supports contractile component, and shields myofibers from mechanical strain. OBJECTIVE Our goal was to determine whether pregnancy alters extracellular matrix mechanical and biochemical properties in a rat model, which may provide insights into the pathogenesis of pelvic floor muscle birth injury. To examine whether pregnancy effects were unique to pelvic floor muscles, we also studied a hind limb muscle. STUDY DESIGN Passive mechanical properties of coccygeus, iliocaudalis, pubocaudalis, and tibialis anterior were compared among 3-month old Sprague-Dawley virgin, late-pregnant, and postpartum rats. Muscle tangent stiffness was calculated as the slope of the stress-sarcomere length curve between 2.5 and 4.0 μm, obtained from a stress-relaxation protocol at a bundle level. Elastin and collagen isoform concentrations were quantified by the use of enzyme-linked immunosorbent assay. Enzymatic and glycosylated collagen crosslinks were determined by high-performance liquid chromatography. Data were compared by the use of repeated-measures, 2-way analysis of variance with Tukey post-hoc testing. Correlations between mechanical and biochemical parameters were assessed by linear regressions. Significance was set to P < .05. Results are reported as mean ± SEM. RESULTS Pregnancy significantly increased stiffness in coccygeus (P < .05) and pubocaudalis (P < .0001) relative to virgin controls, with no change in iliocaudalis. Postpartum, pelvic floor muscle stiffness did not differ from virgins (P > .3). A substantial increase in collagen V in coccygeus and pubocaudalis was observed in late-pregnant, compared with virgin, animals, (P < .001). Enzymatic crosslinks decreased in coccygeus (P < .0001) and pubocaudalis (P < .02) in pregnancy, whereas glycosylated crosslinks were significantly elevated in late-pregnant rats in all pelvic floor muscles (P < .05). Correlations between muscle stiffness and biochemical parameters were inconsistent. In contrast to the changes observed in pelvic floor muscles, the tibialis anterior was unaltered by pregnancy. CONCLUSIONS In contrast to other pelvic tissues, pelvic floor muscle stiffness increased in pregnancy, returning to prepregnancy state postpartum. This adaptation may shield myofibers from excessive mechanical strain during parturition. Biochemical alterations in pelvic floor muscle extracellular matrix due to pregnancy include increase in collagen V and a differential response in enzymatic vs glycosylated collagen crosslinks. The relationships between pelvic floor muscle biochemical and mechanical parameters remain unclear.
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240
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Chen X, Sanchez GN, Schnitzer MJ, Delp SL. Changes in sarcomere lengths of the human vastus lateralis muscle with knee flexion measured using in vivo microendoscopy. J Biomech 2016; 49:2989-2994. [PMID: 27481293 DOI: 10.1016/j.jbiomech.2016.07.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 06/05/2016] [Accepted: 07/16/2016] [Indexed: 11/30/2022]
Abstract
Sarcomeres are the basic contractile units of muscle, and their lengths influence muscle force-generating capacity. Despite their importance, in vivo sarcomere lengths remain unknown for many human muscles. Second harmonic generation (SHG) microendoscopy is a minimally invasive technique for imaging sarcomeres in vivo and measuring their lengths. In this study, we used SHG microendoscopy to visualize sarcomeres of the human vastus lateralis, a large knee extensor muscle important for mobility, to examine how sarcomere lengths change with knee flexion and thus affect the muscle׳s force-generating capacity. We acquired in vivo sarcomere images of several muscle fibers of the resting vastus lateralis in six healthy individuals. Mean sarcomere lengths increased (p=0.031) from 2.84±0.16μm at 50° of knee flexion to 3.17±0.13μm at 110° of knee flexion. The standard deviation of sarcomere lengths among different fibers within a muscle was 0.21±0.09μm. Our results suggest that the sarcomeres of the resting vastus lateralis at 50° of knee flexion are near optimal length. At a knee flexion angle of 110° the resting sarcomeres of vastus lateralis are longer than optimal length. These results show a smaller sarcomere length change and greater conservation of force-generating capacity with knee flexion than estimated in previous studies.
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Affiliation(s)
- Xuefeng Chen
- Department of Mechanical Engineering, Stanford University, United States
| | - Gabriel N Sanchez
- Department of Mechanical Engineering, Stanford University, United States; Department of Bioengineering, Stanford University, United States
| | - Mark J Schnitzer
- Department of Biology, Stanford University, United States; Department of Applied Physics, Stanford University, United States; Howard Hughes Medical Institute, United States
| | - Scott L Delp
- Department of Mechanical Engineering, Stanford University, United States; Department of Bioengineering, Stanford University, United States.
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241
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van der Krogt MM, Bar-On L, Kindt T, Desloovere K, Harlaar J. Neuro-musculoskeletal simulation of instrumented contracture and spasticity assessment in children with cerebral palsy. J Neuroeng Rehabil 2016; 13:64. [PMID: 27423898 PMCID: PMC4947289 DOI: 10.1186/s12984-016-0170-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 06/29/2016] [Indexed: 11/21/2022] Open
Abstract
Background Increased resistance in muscles and joints is an important phenomenon in patients with cerebral palsy (CP), and is caused by a combination of neural (e.g. spasticity) and non-neural (e.g. contracture) components. The aim of this study was to simulate instrumented, clinical assessment of the hamstring muscles in CP using a conceptual model of contracture and spasticity, and to determine to what extent contracture can be explained by altered passive muscle stiffness, and spasticity by (purely) velocity-dependent stretch reflex. Methods Instrumented hamstrings spasticity assessment was performed on 11 children with CP and 9 typically developing children. In this test, the knee was passively stretched at slow and fast speed, and knee angle, applied forces and EMG were measured. A dedicated OpenSim model was created with motion and muscles around the knee only. Contracture was modeled by optimizing the passive muscle stiffness parameters of vasti and hamstrings, based on slow stretch data. Spasticity was modeled using a velocity-dependent feedback controller, with threshold values derived from experimental data and gain values optimized for individual subjects. Forward dynamic simulations were performed to predict muscle behavior during slow and fast passive stretches. Results Both slow and fast stretch data could be successfully simulated by including subject-specific levels of contracture and, for CP fast stretches, spasticity. The RMS errors of predicted knee motion in CP were 1.1 ± 0.9° for slow and 5.9 ± 2.1° for fast stretches. CP hamstrings were found to be stiffer compared with TD, and both hamstrings and vasti were more compliant than the original generic model, except for the CP hamstrings. The purely velocity-dependent spasticity model could predict response during fast passive stretch in terms of predicted knee angle, muscle activity, and fiber length and velocity. Only sustained muscle activity, independent of velocity, was not predicted by our model. Conclusion The presented individually tunable, conceptual model for contracture and spasticity could explain most of the hamstring muscle behavior during slow and fast passive stretch. Future research should attempt to apply the model to study the effects of spasticity and contracture during dynamic tasks such as gait. Electronic supplementary material The online version of this article (doi:10.1186/s12984-016-0170-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marjolein Margaretha van der Krogt
- Department of Rehabilitation Medicine, VU University Medical Center, MOVE Research Institute Amsterdam, PO Box 7057, 1007 MB, Amsterdam, The Netherlands.
| | - Lynn Bar-On
- Department of Rehabilitation Medicine, VU University Medical Center, MOVE Research Institute Amsterdam, PO Box 7057, 1007 MB, Amsterdam, The Netherlands.,Department of Rehabilitation Sciences, KU Leuven, Tervuursevest 101, B-3001, Leuven, Heverlee, Belgium.,Clinical Motion Analysis Laboratory, University Hospital Leuven, Weligerveld 1, 3212, Pellenberg, Belgium
| | - Thalia Kindt
- Clinical Motion Analysis Laboratory, University Hospital Leuven, Weligerveld 1, 3212, Pellenberg, Belgium
| | - Kaat Desloovere
- Department of Rehabilitation Sciences, KU Leuven, Tervuursevest 101, B-3001, Leuven, Heverlee, Belgium.,Clinical Motion Analysis Laboratory, University Hospital Leuven, Weligerveld 1, 3212, Pellenberg, Belgium
| | - Jaap Harlaar
- Department of Rehabilitation Medicine, VU University Medical Center, MOVE Research Institute Amsterdam, PO Box 7057, 1007 MB, Amsterdam, The Netherlands
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242
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Chapman MA, Meza R, Lieber RL. Skeletal muscle fibroblasts in health and disease. Differentiation 2016; 92:108-115. [PMID: 27282924 DOI: 10.1016/j.diff.2016.05.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/23/2016] [Indexed: 02/06/2023]
Abstract
As the primary producer of extracellular matrix (ECM) proteins in skeletal muscle, fibroblasts play an important role providing structural support to muscle. Skeletal muscle ECM is vital for force transduction from muscle cells to tendons and bones to create movement. It is these ECM connections that allow the movement created in muscle to be transmitted to our skeleton. This review discusses how fibroblasts participate in maintaining this healthy ECM within skeletal muscle. Additionally, from a basic science perspective, we discuss current methods to identify and study skeletal muscle fibroblasts, as this is critical to bettering our understanding of these important cells. Finally, skeletal muscle fibrosis is discussed, which is a devastating clinical condition characterized by an overproduction of ECM within skeletal muscle. We discuss the role that fibroblasts and other cells play in muscle fibrosis as well as the implications of this work.
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Affiliation(s)
- Mark A Chapman
- Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Rachel Meza
- Department of Biology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Richard L Lieber
- Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States; Department of Orthopaedic Surgery, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0863, United States; Department of Veteran's Affairs, 9500 Gilman Drive, La Jolla, CA 92093-0863, United States; Rehabilitation Institute of Chicago, 345 East Superior Street, Chicago, IL 60611, United States.
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243
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de Gooijer-van de Groep KL, de Vlugt E, van der Krogt HJ, Helgadóttir Á, Arendzen JH, Meskers CGM, de Groot JH. Estimation of tissue stiffness, reflex activity, optimal muscle length and slack length in stroke patients using an electromyography driven antagonistic wrist model. Clin Biomech (Bristol, Avon) 2016; 35:93-101. [PMID: 27149565 DOI: 10.1016/j.clinbiomech.2016.03.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 03/30/2016] [Accepted: 03/31/2016] [Indexed: 02/07/2023]
Abstract
BACKGROUND About half of all chronic stroke patients experience loss of arm function coinciding with increased stiffness, reduced range of motion and a flexed wrist due to a change in neural and/or structural tissue properties. Quantitative assessment of these changes is of clinical importance, yet not trivial. The goal of this study was to quantify the neural and structural properties contributing to wrist joint stiffness and to compare these properties between healthy subjects and stroke patients. METHODS Stroke patients (n=32) and healthy volunteers (n=14) were measured using ramp-and-hold rotations applied to the wrist joint by a haptic manipulator. Neural (reflexive torque) and structural (connective tissue stiffness and slack lengths and (contractile) optimal muscle lengths) parameters were estimated using an electromyography driven antagonistic wrist model. Kruskal-Wallis analysis with multiple comparisons was used to compare results between healthy subjects, stroke patients with modified Ashworth score of zero and stroke patients with modified Ashworth score of one or more. FINDINGS Stroke patients with modified Ashworth score of one or more differed from healthy controls (P<0.05) by increased tissue stiffness, increased reflexive torque, decreased optimal muscle length and decreased slack length of connective tissue of the flexor muscles. INTERPRETATION Non-invasive quantitative analysis, including estimation of optimal muscle lengths, enables to identify neural and non-neural changes in chronic stroke patients. Monitoring these changes in time is important to understand the recovery process and to optimize treatment.
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Affiliation(s)
- Karin L de Gooijer-van de Groep
- Department of Rehabilitation Medicine, Leiden University Medical Centre, Postzone B0-Q, P.O. Box 9600, 2300 RC Leiden, the Netherlands.
| | - Erwin de Vlugt
- Laboratory for Neuromuscular Control, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, the Netherlands.
| | - Hanneke J van der Krogt
- Department of Rehabilitation Medicine, Leiden University Medical Centre, Postzone B0-Q, P.O. Box 9600, 2300 RC Leiden, the Netherlands.
| | - Áróra Helgadóttir
- Laboratory for Neuromuscular Control, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, the Netherlands.
| | - J Hans Arendzen
- Department of Rehabilitation Medicine, Leiden University Medical Centre, Postzone B0-Q, P.O. Box 9600, 2300 RC Leiden, the Netherlands.
| | - Carel G M Meskers
- Department of Rehabilitation Medicine, Leiden University Medical Centre, Postzone B0-Q, P.O. Box 9600, 2300 RC Leiden, the Netherlands.
| | - Jurriaan H de Groot
- Department of Rehabilitation Medicine, Leiden University Medical Centre, Postzone B0-Q, P.O. Box 9600, 2300 RC Leiden, the Netherlands.
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244
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Ateş F, Temelli Y, Yucesoy CA. The mechanics of activated semitendinosus are not representative of the pathological knee joint condition of children with cerebral palsy. J Electromyogr Kinesiol 2016; 28:130-6. [DOI: 10.1016/j.jelekin.2016.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 04/08/2016] [Accepted: 04/08/2016] [Indexed: 11/17/2022] Open
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245
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Vitiello D, Pochon L, Malatesta D, Girard O, Newman CJ, Degache F. Walking-induced muscle fatigue impairs postural control in adolescents with unilateral spastic cerebral palsy. RESEARCH IN DEVELOPMENTAL DISABILITIES 2016; 53-54:11-18. [PMID: 26851383 DOI: 10.1016/j.ridd.2016.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 01/25/2016] [Accepted: 01/27/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Fatigue is likely to be an important limiting factor in adolescents with spastic cerebral palsy (CP). AIMS To determine the effects of walking-induced fatigue on postural control adjustments in adolescents with unilateral CP and their typically developing (TD) peers. METHODS Ten adolescents with CP (14.2 ± 1.7 yr) and 10 age-, weight- and height-matched TD adolescents (14.1 ± 1.9 yr) walked for 15 min on a treadmill at their preferred walking speed. Before and after this task, voluntary strength capacity of knee extensors (MVC) and postural control were evaluated in 3 conditions: eyes open (EO), eyes closed (EC) and with dual cognitive task (EODT). RESULTS After walking, MVC decreased significantly in CP (-11%, P<0.05) but not in TD. The CoP area was only significantly increased in CP (90%, 34% and 60% for EO, EC and EODT conditions, respectively). The CoP length was significantly increased in the EO condition in CP and TD (20% and 21%) and was significantly increased in the EODT condition by 18% in CP only. CONCLUSIONS Unlike TD adolescents, treadmill walking for 15 min at their preferred speed lead to significant knee extensor strength losses and impairments in postural control in adolescents with unilateral spastic CP.
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Affiliation(s)
- Damien Vitiello
- Laboratory of Fundamental and Applied Bioenergetics, Inserm U1055, University of Grenoble, Grenoble, France; University of Health Sciences, University of Applied Sciences and Arts Western, Lausanne, Switzerland
| | - Ludmilla Pochon
- Institute of Sport Sciences University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland
| | - Davide Malatesta
- Institute of Sport Sciences University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland; Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Olivier Girard
- Institute of Sport Sciences University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland; Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Christopher J Newman
- Pediatric Neurology and Neurorehabilitation Unit, Lausanne University Hospital, Lausanne, Switzerland
| | - Francis Degache
- University of Health Sciences, University of Applied Sciences and Arts Western, Lausanne, Switzerland; Institute of Sport Sciences University of Lausanne (ISSUL), University of Lausanne, Lausanne, Switzerland.
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246
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Drewes E, Driscoll M, Blyum L, Vincentz D. The Effects of a Home-Based Connective Tissue Targeting Therapy on Hip Development in Children With Cerebral Palsy: Six Case Reports. Explore (NY) 2016; 12:268-76. [PMID: 27198038 DOI: 10.1016/j.explore.2016.04.004] [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: 08/30/2015] [Indexed: 10/21/2022]
Abstract
Hip subluxation in children with Cerebral Palsy (CP) has an incidence of 10-30 %, and children with severe CP having the highest incidence. The condition deteriorates if left untreated. Surgery is the most common method used in managing hip subluxation because standard conservative therapies do not improve it. Surgery may have to be repeated and comes at a biological cost to the child. A new home-based CAM, Advanced Biomechanical Rehabilitation (ABR), has shown encouraging results leading to improved spinal stability and stability in sitting in children with severe CP. This case report examines hip development over time in six children with severe CP in the ABR Program. Changes in their clinical picture and pelvic X-Rays are reported. ABR appeared to help stabilize and improve hip subluxation, resulting in these children not requiring further surgical intervention. These findings warrant further investigation of ABR as a noninvasive therapy for hip subluxation.
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Affiliation(s)
- Erika Drewes
- Integrative Family Physician (Private Practice), 15 Budock Road, Claremont, Cape Town 7708.
| | - Mark Driscoll
- Advanced Biomechanical Rehabilitation, Montreal, Pierre-Baillargeons, Canada 11991; Biomedical Research Group, 5135 Bessborough St, Montreal, Canada H4V2S5
| | - Leonid Blyum
- Biomedical Research Group, 5135 Bessborough St, Montreal, Canada H4V2S5
| | - Diane Vincentz
- Advanced Biomechanical Rehabilitation, Horndrupvej 36, Skanderborg 8660, Denmark
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247
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Bernabei M, Maas H, van Dieën JH. A lumped stiffness model of intermuscular and extramuscular myofascial pathways of force transmission. Biomech Model Mechanobiol 2016; 15:1747-1763. [PMID: 27193153 PMCID: PMC5106516 DOI: 10.1007/s10237-016-0795-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 05/03/2016] [Indexed: 12/02/2022]
Abstract
Mechanical behavior of skeletal muscles is commonly modeled under the assumption of mechanical independence between individual muscles within a muscle group. Epimuscular myofascial force transmission via the connective tissue network surrounding a muscle challenges this assumption as it alters the force distributed to the tendons of individual muscles. This study aimed to derive a lumped estimate of stiffness of the intermuscular and extramuscular connective tissues and to assess changes in such stiffness in response to a manipulation of the interface between adjacent muscles. Based on in situ measurements of force transmission in the rat plantar flexors, before and after resection of their connective tissue network, a nonlinear estimate of epimuscular myofascial stiffness was quantified and included in a multi-muscle model with lumped parameters which allows for force transmission depending on the relative position between the muscles in the group. Such stiffness estimate was assessed for a group with normal intermuscular connective tissues and for a group with increased connectivity, mimicking scar tissue development. The model was able to successfully predict the amount of epimuscular force transmission for different experimental conditions than those used to obtain the model parameters. The proposed nonlinear stiffness estimates of epimuscular pathways could be integrated in larger musculoskeletal models, to provide more accurate predictions of force when effects of mechanical interaction or altered epimuscular connections, e.g. after surgery or injury, are substantial.
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Affiliation(s)
- Michel Bernabei
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Van der Boechorststraat 9, 1081, Amsterdam, The Netherlands
| | - Huub Maas
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Van der Boechorststraat 9, 1081, Amsterdam, The Netherlands.
| | - Jaap H van Dieën
- Department of Human Movement Sciences, Vrije Universiteit Amsterdam, MOVE Research Institute Amsterdam, Van der Boechorststraat 9, 1081, Amsterdam, The Netherlands
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248
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Herskind A, Ritterband-Rosenbaum A, Willerslev-Olsen M, Lorentzen J, Hanson L, Lichtwark G, Nielsen JB. Muscle growth is reduced in 15-month-old children with cerebral palsy. Dev Med Child Neurol 2016; 58:485-91. [PMID: 26510820 DOI: 10.1111/dmcn.12950] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/14/2015] [Indexed: 11/28/2022]
Abstract
AIM Lack of muscle growth relative to bone growth may be responsible for development of contractures in children with cerebral palsy (CP). Here, we used ultrasonography to compare growth of the medial gastrocnemius muscle in children with and without CP. METHOD Twenty-six children with spastic CP (15 males, 11 females; mean age 35mo, range 8-65mo) and 101 typically developing children (47 males, 54 females; mean age 29mo, range 1-69mo) were included. Functional abilities of children with CP equalled levels I to III in the Gross Motor Function Classification System. Medial gastrocnemius muscle volume was constructed from serial, transverse, two-dimensional ultrasonography images. RESULTS In typically developing children, medial gastrocnemius volume increased linearly with age. Among children with CP, medial gastrocnemius volume increased less with age and deviated significantly from typically developing children at 15 months of age (p<0.05). Bone length increased with age without significant difference (p=0.49). INTERPRETATION Muscle growth in children with CP initially follows that of typically developing children, but decreases at 15 months of age. This may be related to reduced physical activity and neural activation of the muscle. Interventions stimulating muscle growth in young children with CP may be important to prevent contractures.
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Affiliation(s)
- Anna Herskind
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | - Lars Hanson
- Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark
| | - Glen Lichtwark
- School of Human Movement Studies, University of Queensland, Brisbane, Qld, Australia
| | - Jens B Nielsen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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249
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Sanchez GN, Sinha S, Liske H, Chen X, Nguyen V, Delp SL, Schnitzer MJ. In Vivo Imaging of Human Sarcomere Twitch Dynamics in Individual Motor Units. Neuron 2016; 88:1109-1120. [PMID: 26687220 DOI: 10.1016/j.neuron.2015.11.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/28/2015] [Accepted: 11/10/2015] [Indexed: 12/14/2022]
Abstract
Motor units comprise a pre-synaptic motor neuron and multiple post-synaptic muscle fibers. Many movement disorders disrupt motor unit contractile dynamics and the structure of sarcomeres, skeletal muscle's contractile units. Despite the motor unit's centrality to neuromuscular physiology, no extant technology can image sarcomere twitch dynamics in live humans. We created a wearable microscope equipped with a microendoscope for minimally invasive observation of sarcomere lengths and contractile dynamics in any major skeletal muscle. By electrically stimulating twitches via the microendoscope and visualizing the sarcomere displacements, we monitored single motor unit contractions in soleus and vastus lateralis muscles of healthy individuals. Control experiments verified that these evoked twitches involved neuromuscular transmission and faithfully reported muscle force generation. In post-stroke patients with spasticity of the biceps brachii, we found involuntary microscopic contractions and sarcomere length abnormalities. The wearable microscope facilitates exploration of many basic and disease-related neuromuscular phenomena never visualized before in live humans.
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Affiliation(s)
- Gabriel N Sanchez
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Supriyo Sinha
- Department of Biology, Stanford University, Stanford, CA 94305, USA; Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
| | - Holly Liske
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Xuefeng Chen
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Viet Nguyen
- Department of Neurology, Stanford University, Stanford, CA 94305, USA
| | - Scott L Delp
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA.
| | - Mark J Schnitzer
- Department of Biology, Stanford University, Stanford, CA 94305, USA; Department of Applied Physics, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA.
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250
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Handsfield GG, Meyer CH, Abel MF, Blemker SS. Heterogeneity of muscle sizes in the lower limbs of children with cerebral palsy. Muscle Nerve 2016; 53:933-45. [DOI: 10.1002/mus.24972] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Geoffrey G. Handsfield
- Department of Biomedical Engineering, Health System; University of Virginia; P.O. Box 800759 Charlottesville Virginia 22908 USA
| | - Craig H. Meyer
- Department of Biomedical Engineering, Health System; University of Virginia; P.O. Box 800759 Charlottesville Virginia 22908 USA
- Department of Radiology and Medical Imaging; University of Virginia; Charlottesville Virginia USA
| | - Mark F. Abel
- Department of Orthopaedic Surgery; University of Virginia; Charlottesville Virginia USA
| | - Silvia S. Blemker
- Department of Biomedical Engineering, Health System; University of Virginia; P.O. Box 800759 Charlottesville Virginia 22908 USA
- Department of Orthopaedic Surgery; University of Virginia; Charlottesville Virginia USA
- Department of Mechanical and Aerospace Engineering; University of Virginia; Charlottesville Virginia USA
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