1
|
Romero-Sánchez F, Bermejo-García J, Barrios-Muriel J, Alonso FJ. Design of the Cooperative Actuation in Hybrid Orthoses: A Theoretical Approach Based on Muscle Models. Front Neurorobot 2019; 13:58. [PMID: 31417390 PMCID: PMC6684761 DOI: 10.3389/fnbot.2019.00058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/11/2019] [Indexed: 11/30/2022] Open
Abstract
Hybrid orthoses or rehabilitation exoskeletons have proven to be a powerful tool for subjects with gait disabilities due to their combined use of electromechanical actuation to provide motion and support, and functional electrical stimulation (FES) to contract muscle tissue so as to improve the rehabilitation process. In these devices, each degree of freedom is governed by two actuators. The main issue arises in the design of the two actuation profiles for there to be natural or normative gait motion in which the two actuators are transparent to each other. Hybrid exoskeleton control solutions proposed in the literature have been based on tracking the desired kinematics and applying FES to maintain the desired motion rather than to attain the values expected for physiological movement. This work proposes a muscle-model approach involving inverse dynamics optimization for the design of combined actuation in hybrid orthoses. The FES profile calculated in this way has the neurophysiological meaningfulness for the device to be able to fulfill its rehabilitative purpose. A general scheme is proposed for a hybrid hip-knee-ankle-foot orthosis. The actuation profiles, when muscle tissue is fatigued due to FES actuation are analyzed, and an integrated approach is presented for estimating the actuation profiles so as to overcome muscle peak force reduction during stimulation. The objective is to provide a stimulation profile for each muscle individually that is compatible with the desired kinematics and actuation of the orthosis. The hope is that the results may contribute to the design of subject-specific rehabilitation routines with hybrid exoskeletons, improving the exoskeleton's actuation while maintaining its rehabilitative function.
Collapse
Affiliation(s)
- Francisco Romero-Sánchez
- Department of Mechanical Engineering, Energy and Materials, University of Extremadura, Badajoz, Spain
| | - Javier Bermejo-García
- Department of Mechanical Engineering, Energy and Materials, University of Extremadura, Badajoz, Spain
| | - Jorge Barrios-Muriel
- Department of Mechanical Engineering, Energy and Materials, University of Extremadura, Badajoz, Spain
| | - Francisco J Alonso
- Department of Mechanical Engineering, Energy and Materials, University of Extremadura, Badajoz, Spain
| |
Collapse
|
2
|
Frisk RF, Lorentzen J, Barber L, Nielsen JB. Characterization of torque generating properties of ankle plantar flexor muscles in ambulant adults with cerebral palsy. Eur J Appl Physiol 2019; 119:1127-1136. [PMID: 30778762 DOI: 10.1007/s00421-019-04102-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 02/12/2019] [Indexed: 01/12/2023]
Abstract
PURPOSE Weakness of plantar flexor muscles is related to reduced push-off and forward propulsion during gait in persons with cerebral palsy (CP). It has not been clarified to what an extent altered muscle contractile properties contribute to this muscle weakness. Here, we investigated the torque generating capacity and muscle fascicle length in the triceps surae muscle throughout ankle range of motion (ROM) in adults with CP using maximal single muscle twitches elicited by electrical nerve stimulation and ultrasonography. METHODS Fourteen adults with CP (age 36, SD 10.6, GMFCS I-III) and 17 neurological intact (NI) adults (age 36, SD 4.5) participated. Plantar flexor torque during supramaximal stimulation of the tibial nerve was recorded in a dynamometer at 8 ankle angles throughout ROM. Medial gastrocnemius (MG) fascicle length was tracked using ultrasonography. RESULTS Adults with CP showed reduced plantar flexor torque and fascicle shortening during supramaximal stimulation throughout ROM. The largest torque generation was observed at the ankle joint position where the largest shortening of MG fascicles was observed in both groups. This was at a more plantarflexed position in the CP group. CONCLUSION Reduced torque and fascicle shortening during supramaximal stimulation of the tibial nerve indicate impaired contractile properties of plantar flexor muscles in adults with CP. Maximal torque was observed at a more plantarflexed position in adults with CP indicating an altered torque-fascicle length/ankle angle relation. The findings suggest that gait rehabilitation in adults with CP may require special focus on improvement of muscle contractility.
Collapse
Affiliation(s)
- Rasmus Feld Frisk
- Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen N, Denmark. .,Professionshøjskolen Absalon, Roskilde, Denmark. .,Elsass Institute, Charlottenlund, Denmark.
| | - Jakob Lorentzen
- Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen N, Denmark.,Elsass Institute, Charlottenlund, Denmark
| | - Lee Barber
- School of Health, Medical and Allied Sciences, Central Queensland University, Bundaberg, Australia.,Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Australia
| | - Jens Bo Nielsen
- Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen N, Denmark.,Elsass Institute, Charlottenlund, Denmark
| |
Collapse
|
3
|
Mirbagheri MM, Kindig MW, Niu X. Effects of robotic-locomotor training on stretch reflex function and muscular properties in individuals with spinal cord injury. Clin Neurophysiol 2014; 126:997-1006. [PMID: 25449559 DOI: 10.1016/j.clinph.2014.09.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE We sought to determine the therapeutic effect of robotic-assisted step training (RAST) on neuromuscular abnormalities associated with spasticity by characterization of their recovery patterns in people with spinal cord injury (SCI). METHODS Twenty-three motor-incomplete SCI subjects received one-hour RAST sessions three times per week for 4 weeks, while an SCI control group received no training. Neuromuscular properties were assessed using ankle perturbations prior to and during the training, and a system-identification technique quantified stretch reflex and intrinsic stiffness magnitude and modulation with joint position. Growth-mixture modeling classified subjects based on similar intrinsic and reflex recovery patterns. RESULTS All recovery classes in the RAST group presented significant (p<0.05) reductions in intrinsic and reflex stiffness magnitude and modulation with position; the control group presented no changes over time. Subjects with larger baseline abnormalities exhibited larger reductions, and over longer training periods. CONCLUSIONS Our findings demonstrate that RAST can effectively reduce neuromuscular abnormalities, with greater improvements for subjects with higher baseline abnormalities. SIGNIFICANCE Our findings suggest, in addition to its primary goal of improving locomotor patterns, RAST can also reduce neuromuscular abnormalities associated with spasticity. These findings also demonstrate that these techniques can be used to characterize neuromuscular recovery patterns in response to various types of interventions.
Collapse
Affiliation(s)
- Mehdi M Mirbagheri
- Department of Physical Medicine and Rehabilitation, Northwestern University, USA; Sensory Motor Performance Program, Rehabilitation Institute of Chicago, USA.
| | - Matthew W Kindig
- Sensory Motor Performance Program, Rehabilitation Institute of Chicago, USA
| | - Xun Niu
- Department of Physical Medicine and Rehabilitation, Northwestern University, USA; Sensory Motor Performance Program, Rehabilitation Institute of Chicago, USA
| |
Collapse
|
4
|
D'Amico JM, Condliffe EG, Martins KJB, Bennett DJ, Gorassini MA. Recovery of neuronal and network excitability after spinal cord injury and implications for spasticity. Front Integr Neurosci 2014; 8:36. [PMID: 24860447 PMCID: PMC4026713 DOI: 10.3389/fnint.2014.00036] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 04/17/2014] [Indexed: 01/08/2023] Open
Abstract
The state of areflexia and muscle weakness that immediately follows a spinal cord injury (SCI) is gradually replaced by the recovery of neuronal and network excitability, leading to both improvements in residual motor function and the development of spasticity. In this review we summarize recent animal and human studies that describe how motoneurons and their activation by sensory pathways become hyperexcitable to compensate for the reduction of functional activation of the spinal cord and the eventual impact on the muscle. Specifically, decreases in the inhibitory control of sensory transmission and increases in intrinsic motoneuron excitability are described. We present the idea that replacing lost patterned activation of the spinal cord by activating synaptic inputs via assisted movements, pharmacology or electrical stimulation may help to recover lost spinal inhibition. This may lead to a reduction of uncontrolled activation of the spinal cord and thus, improve its controlled activation by synaptic inputs to ultimately normalize circuit function. Increasing the excitation of the spinal cord with spared descending and/or peripheral inputs by facilitating movement, instead of suppressing it pharmacologically, may provide the best avenue to improve residual motor function and manage spasticity after SCI.
Collapse
Affiliation(s)
- Jessica M D'Amico
- Centre for Neuroscience, University of Alberta Edmonton, AB, Canada ; Faculty of Medicine and Dentistry, University of Alberta Edmonton, AB, Canada
| | - Elizabeth G Condliffe
- Centre for Neuroscience, University of Alberta Edmonton, AB, Canada ; Faculty of Medicine and Dentistry, University of Alberta Edmonton, AB, Canada ; Department of Biomedical Engineering, University of Alberta Edmonton, AB, Canada ; Division of Physical Medicine and Rehabilitation, University of Alberta Edmonton, AB, Canada
| | - Karen J B Martins
- Centre for Neuroscience, University of Alberta Edmonton, AB, Canada ; Faculty of Physical Education and Recreation, University of Alberta Edmonton, AB, Canada
| | - David J Bennett
- Centre for Neuroscience, University of Alberta Edmonton, AB, Canada ; Faculty of Rehabilitation Medicine, University of Alberta Edmonton, AB, Canada
| | - Monica A Gorassini
- Centre for Neuroscience, University of Alberta Edmonton, AB, Canada ; Faculty of Medicine and Dentistry, University of Alberta Edmonton, AB, Canada ; Department of Biomedical Engineering, University of Alberta Edmonton, AB, Canada
| |
Collapse
|
5
|
Van Dyke JM, Bain JL, Riley DA. Stretch-activated signaling is modulated by stretch magnitude and contraction. Muscle Nerve 2013; 49:98-107. [DOI: 10.1002/mus.23880] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Jonathan M. Van Dyke
- Department of Cell Biology; Neurobiology & Anatomy, Medical College of Wisconsin; 8701 Watertown Plank Road Milwaukee Wisconsin 53226 USA
| | - James L.W. Bain
- Department of Cell Biology; Neurobiology & Anatomy, Medical College of Wisconsin; 8701 Watertown Plank Road Milwaukee Wisconsin 53226 USA
| | - Danny A. Riley
- Department of Cell Biology; Neurobiology & Anatomy, Medical College of Wisconsin; 8701 Watertown Plank Road Milwaukee Wisconsin 53226 USA
| |
Collapse
|
6
|
Stimulation of Shank Muscles During Functional Electrical Stimulation Cycling Increases Ankle Excursion in Individuals With Spinal Cord Injury. Arch Phys Med Rehabil 2012; 93:1930-6. [PMID: 22634232 DOI: 10.1016/j.apmr.2012.05.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 05/06/2012] [Accepted: 05/14/2012] [Indexed: 11/23/2022]
|
7
|
Van Dyke JM, Bain JLW, Riley DA. Preserving sarcomere number after tenotomy requires stretch and contraction. Muscle Nerve 2012; 45:367-75. [PMID: 22334171 DOI: 10.1002/mus.22286] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Passive stretch therapy is utilized to improve the range of motion of chronically shortened muscles. However, human studies show conflicting results as whether passive stretch is clinically effective. METHODS The soleus muscles of adult rats were tenotomized to induce muscle shortening adaptation. Muscles included were non-treated normal, subjected to daily static stretch, or lengthened and isometrically contracted for 20 min/day. Muscle fiber structure was analyzed histochemically. Sarcomeres per millimeter length were counted to assess the effect of treatment. RESULTS Passive stretch significantly reduced central core lesion formation, but sarcomere loss was not prevented. The addition of isometric contraction during static stretch significantly (P < 0.001) reduced sarcomere loss. CONCLUSIONS Passive stretch alone does not prevent shortening adaptation. Contraction is required in combination with stretch to preserve the number of sarcomeres in series. The combination of stretch and contraction is necessary to maintain proper muscle fiber length.
Collapse
Affiliation(s)
- Jonathan M Van Dyke
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226, USA
| | | | | |
Collapse
|
8
|
de Vlugt E, de Groot JH, Wisman WHJ, Meskers CGM. Clonus is explained from increased reflex gain and enlarged tissue viscoelasticity. J Biomech 2011; 45:148-55. [PMID: 22014329 DOI: 10.1016/j.jbiomech.2011.09.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 09/07/2011] [Accepted: 09/13/2011] [Indexed: 11/29/2022]
Abstract
Upper motor neuron diseases (UMND), such as stroke and spinal cord injury (SCI), are assumed to produce alterations in muscle tissue in association with neural damage. Distinguishing between these two factors is of clinical importance in choosing appropriate therapy. We studied the effect of changes in the gain of the Ia reflex pathway and tissue viscoelasticity on the emergence, frequency, and persistence of ankle clonus: a clinically significant, involuntary oscillatory movement disorder. Monte Carlo simulations were performed to explain our experimental observations in patients with stroke (n = 3) and SCI (n = 4) using a nonlinear antagonistic muscle model of the human ankle joint. Ia reflex gain was varied by changing motor unit pool threshold and gain, and passive tissue viscosity and elasticity were varied by changing optimal muscle length. Tissue viscoelasticity appeared to have a strong effect on the emergence and persistence of clonus. Observed frequencies of ankle movement, prior to and after the experimental intervention of a sudden damper, was predicted by the model. The simulations revealed that reflex gains were largest in patients with the largest tissue viscoelasticity. We conclude that ankle clonus in stroke and SCI is the result of a combination of, and suggests a relation between, (i) a decrease in threshold and an increase in gain of the motor unit pool and (ii) a decrease in optimal muscle length.
Collapse
Affiliation(s)
- Erwin de Vlugt
- Department of Mechanical Engineering, Laboratory of Neuromuscular Control, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands.
| | | | | | | |
Collapse
|
9
|
Dudley-Javoroski S, McMullen T, Borgwardt MR, Peranich LM, Shields RK. Reliability and responsiveness of musculoskeletal ultrasound in subjects with and without spinal cord injury. ULTRASOUND IN MEDICINE & BIOLOGY 2010; 36:1594-1607. [PMID: 20800961 PMCID: PMC2948870 DOI: 10.1016/j.ultrasmedbio.2010.07.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 07/22/2010] [Accepted: 07/26/2010] [Indexed: 05/29/2023]
Abstract
Rehabilitation after spinal cord injury (SCI) aims to preserve the integrity of the paralyzed musculoskeletal system. The suitability of ultrasound (US) for delineating training-related muscle/tendon adaptations after SCI is unknown. The purpose of this study was to quantify within- and between-operator reliability for US and to determine its responsiveness to post-training muscle/tendon adaptations in SCI subjects. Two novice operators and one experienced operator obtained sonographic images of the vastus lateralis, patellar tendon, soleus, and Achilles tendon from seven SCI subjects and 16 controls. For control subjects, within-operator concordance (ICC [3,1]) ranged from 0.58 to 0.95 for novice operators and exceeded 0.86 for the experienced operator. Between-operator concordance (ICC [2,1]) ranged from 0.62 to 0.74. Ultrasound detected muscle hypertrophy (p < 0.05) following electrical stimulation training in subjects with SCI (responsiveness) but did not detect differences in tendon thickness. These error estimates support the utility of US in future post-SCI training studies.
Collapse
Affiliation(s)
- Shauna Dudley-Javoroski
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City Iowa
| | - Tara McMullen
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City Iowa
| | | | - Lauren M. Peranich
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City Iowa
| | - Richard K. Shields
- Physical Therapy and Rehabilitation Science, Carver College of Medicine, The University of Iowa, Iowa City Iowa
| |
Collapse
|
10
|
Bittar CK, Cliquet A. Effects of quadriceps and anterior tibial muscles electrical stimulation on the feet and ankles of patients with spinal cord injuries. Spinal Cord 2010; 48:881-5. [PMID: 20479766 DOI: 10.1038/sc.2010.50] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Controlled clinical test. OBJECTIVES The purpose of this study was to assess the effects of quadriceps and anterior tibial muscles electrical stimulation on the feet and ankles of patients with spinal cord injuries and to compare them with able-bodied individuals and a group of patients who did not undergo neuromuscular electrical stimulation (NMES). SETTING This study was conducted at the Hospital das Clínicas of Unicamp, Campinas, São Paulo, Brazil. METHODS Between January and April 2008, 30 patients at the spinal cord injury ambulatory clinic who underwent NMES (group A) were submitted to a clinical and radiographic assessment of their feet and ankles and compared with a spinal cord injury group (group B) who did not undergo NMES and a group of able-bodied individuals (group C). The Kruskal-Wallis test was used to compare all the three groups, and between-group differences (P<0.05) were investigated with the Mann-Whitney test. RESULTS The mean mobility of the midfoot and ankle subtalar joint was significantly higher in group C than in groups A and B. Differences in the mean measurements of the profiles of the talocalcaneal and the talus-first metatarsal angles were statistically significant for group A vs the other groups (P=0.0020, 0.0024, respectively). Foot deformities were found in groups including claw toes and flat feet (group A) and grade I ulcers on the lateral malleolus and calcaneus (group B). CONCLUSION Partial-load NMES maintains the feet and ankles in a planted and adequate walking position in patients with spinal cord injuries, a favorable result of new technologies that allows these patients to reacquire independent walking capacity.
Collapse
Affiliation(s)
- C K Bittar
- Orthopaedics Department, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, Brazil.
| | | |
Collapse
|
11
|
The force-length curves of the human rectus femoris and gastrocnemius muscles in vivo. J Appl Biomech 2010; 26:45-51. [PMID: 20147757 DOI: 10.1123/jab.26.1.45] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
For a physiologically realistic joint range of motion and therefore range of muscle fiber lengths, only part of the whole muscle force-length curve can be used in vivo; that is, only a section of the force-length curve is expressed. Previous work has determined that the expressed section of the force-length curve for individual muscles can vary between subjects; however, the degree of intersubject variability is different for different muscles. This study determined the expressed section of both the rectus femoris and gastrocnemius--muscles with very different ratios of tendon slack length to muscle fiber optimum length--for 28 nonspecifically trained subjects to test the hypothesis that the value of this ratio affects the amount of variability in the expressed section. The force-length curves of the two muscles were reconstructed from moment-angle data using the method of Herzog & ter Keurs (1988). There was no relationship between the expressed sections of the force-length curve for the two muscles. Less variability was found in the expressed section of the gastrocnemius compared with the rectus femoris, supporting the hypothesis. The lack of relationship between the expressed sections of the two muscles has implications for motor control and for training muscle for rehabilitation.
Collapse
|
12
|
Erworbene Kontrakturen der Gelenke im höheren Lebensalter. Z Gerontol Geriatr 2010; 43:147-57. [PMID: 20069303 DOI: 10.1007/s00391-009-0089-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 08/18/2009] [Indexed: 10/20/2022]
|
13
|
Pelletier CA, Hicks AL. The length-tension relationship of human dorsiflexor and plantarflexor muscles after spinal cord injury. Spinal Cord 2009; 48:202-6. [PMID: 19721452 DOI: 10.1038/sc.2009.106] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN A cross-sectional design. OBJECTIVES To examine the length-tension relationship of dorsiflexion (DF) and plantarflexion (PF) muscle groups in seven individuals with chronic spinal cord injury (SCI; C2-T7; age 43+/-10.1 years) and compare it with a group of age and sex-matched able-bodied (AB) controls. SETTING McMaster University, Hamilton, ON, Canada. METHODS Isometric single twitch properties, 0.5-s tetanic contractions (SCI) and maximal voluntary contractions (AB) were measured at nine joint angles from 20 degrees DF to 20 degrees PF. RESULTS In the DF muscles, peak-evoked twitch (PT) torque occurred at 20 degrees PF for SCI (3.4+/-1.1 N m) and AB (3.8+/-1.4 N m) with no difference in peak torque between groups, whereas peak summated force occurred at 10 degrees PF in AB and 20 degrees PF in SCI (P<0.01). In the PF muscles, PT torque occurred at 15 degrees DF in AB (18.6+/-2.6 N m) and at 5 degrees DF (6.8+/-3.3 N m; P<0.01) in SCI, and peak-summated force occurred at 15 degrees DF in AB. The SCI group did not show any change in PF peak-summated force with varying joint angles. Rates of contraction and relaxation were not different between the two groups. CONCLUSIONS The results suggest a significant change in the length-tension relationship of the PF muscles after SCI, but no change in the DF muscle group. Rehabilitation programs should focus on maintaining PF muscle length in order to optimize muscle strength and function after SCI.
Collapse
Affiliation(s)
- C A Pelletier
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | | |
Collapse
|
14
|
Gao F, Zhang LQ. Altered contractile properties of the gastrocnemius muscle poststroke. J Appl Physiol (1985) 2008; 105:1802-8. [PMID: 18948443 DOI: 10.1152/japplphysiol.90930.2008] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Spasticity, contracture and muscle weakness often occur together poststroke and cause considerable motor impairments to stroke survivors. The underlying changes in contractile properties of muscle fascicles are still not clear. The purpose of this study was to investigate the contractile property changes of the medial gastrocnemius muscle fascicles poststroke. Ten stroke survivors and ten healthy subjects participated in the study. The medial gastrocnemius fascicular length was measured at various combinations of ankle and knee positions using ultrasonography, with the muscle activated selectively using electrical stimulation. The stimulation intensity was kept constant across different ankle and knee positions to establish the active force-length relationship of the muscle fascicles. It was found that stroke survivors showed a shift of the force-length curve with a significantly shorter optimal fascicle length (33.2 +/- 3.2 mm) compared with that of healthy controls (47.4 +/- 2.7 mm) with P < 0.001. Furthermore, the width span of the fascicular force-length curve of stroke survivors was significantly narrower with steeper slopes than that of controls (P <or= 0.001), suggesting reduced number of sarcomeres along the fascicles and/or reduced sarcomere length poststroke. Regression analysis showed that the medial gastrocnemius fascicular length of stroke survivors varied significantly less with ankle and knee flexions (P <or= 0.001) than that of controls, suggesting shorter and stiffer muscle fascicles poststroke, which might be attributed to muscle architectural adaptation. This study showed that there are considerable changes in the contractile properties of muscle fascicles poststroke, which may contribute directly to the joint-level changes of decreased range of motion, increased stiffness, muscle weakness, and impaired motor functions in stroke survivors.
Collapse
Affiliation(s)
- Fan Gao
- Rehabilitation Institute of Chicago, Suite 1406, 345 East Superior St. Chicago, IL 60611, USA
| | | |
Collapse
|
15
|
Harvey LA, Herbert RD, Glinsky J, Moseley AM, Bowden J. Effects of 6 months of regular passive movements on ankle joint mobility in people with spinal cord injury: a randomized controlled trial. Spinal Cord 2008; 47:62-6. [DOI: 10.1038/sc.2008.71] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
Chou LW, Binder-Macleod SA. The effects of stimulation frequency and fatigue on the force-intensity relationship for human skeletal muscle. Clin Neurophysiol 2007; 118:1387-96. [PMID: 17466581 PMCID: PMC1993846 DOI: 10.1016/j.clinph.2007.02.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Revised: 01/26/2007] [Accepted: 02/21/2007] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Functional electrical stimulation (FES) has not gained widespread application for a number of factors; two of which are rapid muscle fatigue and imprecise control in force. Stimulation intensity is adjusted during FES to overcome the decline in muscle force due to fatigue and precisely control muscle force output. The purpose of this study was to understand the relationship between muscle force output and stimulation intensity and to see how this relationship changes with fatigue. METHODS Quadriceps femoris muscles of 10 able-bodied adults were tested isometrically. Pre- and post-fatigue muscle force responses to stimulation trains with different intensities and frequencies were recorded and analyzed. In addition, a case study using a subject with spinal cord injury was presented to illustrate the use of the force-intensity relationship to reduce muscle fatigue and improve the control of muscle force during repetitive electrical stimulation. RESULTS An exponential relationship between muscle force and stimulation intensity was observed; interestingly, the normalized force-intensity relationship did not change with stimulation frequency or fatigue. CONCLUSIONS The observed consistencies in the force-intensity relationship should assist scientists and clinicians to more accurately predict the forces produced by a muscle with changes in pulse duration during repetitive electrical stimulation. SIGNIFICANCE The findings of this study provide guidelines for clinicians and researchers to adjust the stimulation intensity to achieve precise control of force repetitively during the application of FES.
Collapse
Affiliation(s)
- Li-Wei Chou
- Biomechanics and Movement Science Program, University of Delaware, Newark, DE, USA
| | | |
Collapse
|
17
|
Shields RK, Dudley-Javoroski S. Musculoskeletal adaptations in chronic spinal cord injury: effects of long-term soleus electrical stimulation training. Neurorehabil Neural Repair 2007; 21:169-79. [PMID: 17312092 PMCID: PMC3270314 DOI: 10.1177/1545968306293447] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE The purpose of this study was to determine whether long-term electrical stimulation training of the paralyzed soleus could change this muscle's physiological properties (torque, fatigue index, potentiation index, torque-time integral) and increase tibia bone mineral density. METHODS Four men with chronic (>2 years) complete spinal cord injury (SCI; American Spinal Injury Association classification A) trained 1 soleus muscle using an isometric plantar flexion electrical stimulation protocol. The untrained limb served as a within-subject control. The protocol involved ~ 30 minutes of training each day, 5 days a week, for a period of 6 to 11 months. Mean compliance over 11 months of training was 91% for 3 subjects. A fourth subject achieved high compliance after only 5 months of training. Mean estimated compressive loads delivered to the tibia were approximately 110% of body weight. Over the 11 months of training, the muscle plantar flexion torque, fatigue index, potentiation index, and torque-time integral were evaluated periodically. Bone mineral density (dual-energy x-ray absorptiometry) was evaluated before and after the training program. RESULTS The trained limb fatigue index, potentiation index, and torque-time integral showed rapid and robust training effects (P<.05). Soleus electrical stimulation training yielded no changes to the proximal tibia bone mineral density, as measured by dual-energy x-ray absorptiometry. The subject with low compliance experienced fatigue index and torque-time integral improvements only when his compliance surpassed 80%. In contrast, his potentiation index showed adaptations even when compliance was low. CONCLUSIONS These findings highlight the persistent adaptive capabilities of chronically paralyzed muscle but suggest that preventing musculoskeletal adaptations after SCI may be more effective than reversing changes in the chronic condition.
Collapse
Affiliation(s)
- Richard K Shields
- Graduate Program in Physical Therapy and Rehabilitation Science, The University of Iowa, Iowa City, IA 52242-1190, USA.
| | | |
Collapse
|
18
|
Shields RK, Dudley-Javoroski S. Musculoskeletal plasticity after acute spinal cord injury: effects of long-term neuromuscular electrical stimulation training. J Neurophysiol 2006; 95:2380-90. [PMID: 16407424 PMCID: PMC3298883 DOI: 10.1152/jn.01181.2005] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Maintaining the physiologic integrity of paralyzed limbs may be critical for those with spinal cord injury (SCI) to be viable candidates for a future cure. No long-term intervention has been tested to attempt to prevent the severe musculoskeletal deterioration that occurs after SCI. The purposes of this study were to determine whether a long-term neuromuscular electrical stimulation training program can preserve the physiological properties of the plantar flexor muscles (peak torque, fatigue index, torque-time integral, and contractile speed) as well as influence distal tibia trabecular bone mineral density (BMD). Subjects began unilateral plantar flexion electrical stimulation training within 6 wk after SCI while the untrained leg served as a control. Mean compliance for the 2-yr training program was 83%. Mean estimated compressive loads delivered to the tibia were approximately 1-1.5 times body weight. The training protocol yielded significant trained versus untrained limb differences for torque (+24%), torque-time integral (+27%), fatigue index (+50%), torque rise time (+45%), and between-twitch fusion (+15%). These between-limb differences were even greater when measured at the end of a repetitive stimulation protocol (125 contractions). Peripheral quantitative computed tomography revealed 31% higher distal tibia trabecular BMD in trained limbs than in untrained limbs. The intervention used in this study was sufficient to limit many of the deleterious muscular and skeletal adaptations that normally occur after SCI. Importantly, this method of load delivery was feasible and may serve as the basis for an intervention to preserve the musculoskeletal properties of individuals with SCI.
Collapse
Affiliation(s)
- Richard K Shields
- Graduate Program in Physical Therapy and Rehabilitation Science, The University of Iowa, Iowa City, IA 52242-1190, USA.
| | | |
Collapse
|
19
|
Harvey L, de Jong I, Goehl G, Mardwedel S. Twelve weeks of nightly stretch does not reduce thumb web-space contractures in people with a neurological condition: a randomised controlled trial. ACTA ACUST UNITED AC 2006; 52:251-8. [PMID: 17132119 DOI: 10.1016/s0004-9514(06)70004-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
QUESTION What is the effectiveness of 12 weeks of nightly stretch in reducing thumb web-space contracture in people with neurological conditions? DESIGN Assessor-blinded, randomised controlled trial. PARTICIPANTS Forty-four (one dropout)community-dwelling patients with a neurological condition (14 stroke, 7 traumatic brain injury, 23 spinal cord injury) who had uni or bilateral thumb web-space contractures (60 thumbs). INTERVENTION The experimental thumbs were splinted into a stretched,abducted position each night for 12 weeks. The control thumbs were not splinted. OUTCOME MEASURES Thumb web-space was measured as the carpometacarpal angle during the application of a 0.9 Nm abduction torque before and after intervention. RESULTS The mean increase in thumb web-space after 12 weeks was 1 deg (95% CI, -1 to 2). CONCLUSION Intensive stretch administered regularly over three months does not reduce thumb web-space contractures in neurological conditions.
Collapse
Affiliation(s)
- Lisa Harvey
- Rehabilitation Studies Unit, Royal Rehabilitation Centre Sydney, Ryde, NSW 1680, Australia.
| | | | | | | |
Collapse
|