Fall experiences from the perspectives of people with osteoarthritis: in their own words.

PURPOSE: To explore real-life experiences of people with osteoarthritis (OA) to increase understanding of how they perceive contributing factors to falls, circumstances at time of falls, and consequences of falls. MATERIALS AND METHODS: Four focus groups of 3-7 people with OA from the Chicago, IL, USA, and neighboring areas were conducted remotely via web-based videoconferencing. Inclusion criteria included history of falls in previous 12 months and hip and/or knee OA. Focus group transcripts were coded and analyzed using a modified grounded theory approach to identify themes. RESULTS: Focus group participants (n = 17) described experiences associated with fall-related events that resulted in the identification of four themes: (1) perception of falls and fall risks can be influenced by OA symptoms, (2) ability to remember circumstances of falls are influenced by consequences, (3) behaviors and attitudes that address OA symptoms and avoidance of falls are similar and (4) OA symptoms and falls have common psychological impacts on lives. CONCLUSION: Our study highlights how people with OA define falls, perceive contributing factors to falls, and describe general and OA-related factors that contributed to their fall experiences. The shared experiences contributed to the creation of themes that represented various aspects of the circumstances and impact of falls. Consideration for the identified themes may enhance recording and reporting of falls, contribute to development of improved fall risk assessment tools, and prioritize research into the biopsychosocial effects of falls in people with OA.IMPLICATIONS FOR REHABILITATIONInformation about circumstances of a fall such as location, activity, and symptoms of osteoarthritis may be beneficial in creating tailored fall prevention training and education.Falls are a common problem for people with lower limb osteoarthritis that can lead to negative changes in activity and quality of life.The psychological impact of osteoarthritis symptoms may be contributing to fear of falling and decrease participation in daily activities.Awareness of the perceptions people with osteoarthritis have about their symptoms may provide educational and training opportunities to address the benefits of different therapeutic treatments.Awareness of perceptions people with osteoarthritis have about their risk of falling may provide educational and training opportunities to address the benefits of different therapeutic treatments.

Fall-related events in people who are lower limb prosthesis users: the lived experience.

PURPOSE: To explore lived experiences, and identify common themes as well as vocabulary associated with fall-related events in lower limb prosthesis (LLP) users. MATERIALS AND METHODS: Five focus groups of LLP users from across the United States were conducted remotely via video or tele-conferencing. Focus group transcripts were coded and analyzed using methods adapted from a grounded theory approach to identify themes. RESULTS: Focus group participants (n = 25) described experiences associated with fall-related events that resulted in the identification of six themes: (1) memories of fall-related events are shaped by time and context, (2) location and ground conditions influence whether falls occur, (3) some activities come with more risk, (4) fall-related situations are multi-faceted, and often involve the prosthesis, (5) how LLP users land, but not the way they go down, tends to vary, and (6) not all falls affect LLP users, but some near-falls do. CONCLUSION: Consideration for where LLP users fall, what they are doing when they fall, how they fall, what occurs as a result of a fall, and how well memory of a fall persists may enhance recording and reporting of falls, contribute to development of improved fall risk assessment tools, and inspire the design and function of prosthetic componentry for patient safety.Implications for rehabilitationFalls are a common problem in lower limb prosthesis (LLP) users that can lead to adverse health outcomes.Concerns over near falls, not just falls, may merit greater attention from rehabilitation professionals.Elements of the lived experience that appear unique to LLP users include the role of prosthetic fit, function, and comfort in losing and/or recovering balance; as well as the tendency of LLP users to modify rather than stop or avoid activities associated with falls.

Interrater and Test-Retest Reliability of Performance-Based Clinical Tests Administered to Established Users of Lower Limb Prostheses.

OBJECTIVE: A major barrier to reducing falls among users of lower limb prostheses (LLP) has been an absence of statistical indices required for clinicians to select and interpret scores from performance-based clinical tests. The study aimed to derive estimates of reliability, measurement error, and minimal detectable change values in performance-based clinical tests administered to unilateral LLP users. METHODS: A total of 60 unilateral LLP users were administered the Narrowing Beam Walking Test, Timed ``Up and Go'' (TUG), Four Square Step Test (FSST), and 10-Meter Walk Test on 2 occasions, 3 to 9 days apart. Intraclass correlation coefficients (ICCs) were calculated to assess interrater and test-retest reliability, while standard error of measurement (SEM) and minimal detectable change (MDC90) were derived to establish estimates of measurement error in individual scores or changes in score for each test. RESULTS: Interrater reliability ICCs (1,1) were high for all tests (ie, ≥0.98). Test-retest ICCs (2,1) varied by test, ranging from .88 for the TUG to .97 for the FSST. SEM and MDC90 varied between .39 and .96 and between .91 seconds and 2.2 seconds for the time-based tests (FSST, TUG, 10-Meter Walk Test). SEM and MDC90 for the Narrowing Beam Walking Test were .07 and .16, respectively. CONCLUSION: With the exception of the TUG, studied tests had test-retest ICCs (2,1) that exceeded the minimum required threshold to be considered suitable for group- and individual-level applications (ie, ICC ≥ 0.70 and ≥ 0.90, respectively). Future research on individuals with dysvascular and transfemoral amputations or in specific age categories is required. IMPACT: Along with published validity indices, these reliability, error, and change indices can help clinicians select balance tests suitable for LLP users. They can also help clinicians interpret test scores to make informed, evidence-based clinical decisions.

Speed impacts frontal-plane maneuver stability of individuals with incomplete spinal cord injury.

BACKGROUND: Following incomplete spinal cord injury, people often move slowly in an effort to maintain stability during walking maneuvers. Here we examine how maneuver speed impacts frontal-plane stability in people with incomplete spinal cord injury. We hypothesized that the challenge to control frontal-plane stability would increase with maneuver speed; specifically, the minimum lateral margin of stability would be smaller and the required coefficient of friction to avoid a slip would be greater during fast vs. preferred speed maneuvers. METHODS: We measured kinematics and ground reaction forces as 12 individuals with incomplete spinal cord injury performed side-step, lateral maneuvers at preferred and fast speeds. We examined four sequential steps: the Setup and Pushoff steps initiated the maneuver, and the Landing and Recovery steps arrested the maneuver. FINDINGS: Our hypotheses were partially supported. Maneuver time was shorter during fast vs. preferred speed maneuvers (p = 0.003). Minimum lateral margin of stability was smaller during the Setup step of fast vs. preferred speed maneuvers (p = 0.026). We found no differences in minimum lateral margin of stability between speeds for the Landing and Recovery steps (p > 0.05). The required coefficient of friction was not different between fast and preferred speed maneuvers (p = 0.087). INTERPRETATION: The greatest effect of increasing maneuver speed occurred during the Setup step; as speed increased, participants reduced their minimum lateral margin of stability ipsilateral to the maneuver direction. This action allowed maneuvers to be performed more quickly without requiring a greater lateral impulse during the Pushoff step. However, this strategy reduced passive stability.

Use of Pelvic Corrective Force With Visual Feedback Improves Paretic Leg Muscle Activities and Gait Performance After Stroke.

The purpose of this study was to examine the effects of combined pelvic corrective force and visual feedback during treadmill walking on paretic leg muscle activity and gait characteristics in individuals with post-stroke hemiparesis. Fifteen chronic stroke participants completed visual feedback only and combined pelvic corrective force and visual feedback conditions during treadmill walking. Each condition included: 1-minute baseline, 7-minute training with visual feedback only or additional pelvic corrective force, 1-minute post training, 1-minute standing break, and another 5-minute training. EMGs from the paretic leg muscles and step length were measured. Overground walking was evaluated before treadmill walking, immediately and 10 minutes after treadmill walking. Greater increases in integrated EMG of all muscles, except vastus medialis and tibialis anterior, were observed with the application of additional pelvic corrective force compared to visual feedback only during treadmill walking. Overground walking speed significantly increased after treadmill training with combined pelvic correction force and visual feedback, but was not significant for the visual feedback only condition. Voluntary weight shifting with additional pelvic corrective force enhanced paretic leg muscle activities and improved gait characteristics during walking. Individuals with post-stroke hemiparesis could adapt feedforward control and generalize the adaptation to overground walking.

Forced use of paretic leg induced by constraining the non-paretic leg leads to motor learning in individuals post-stroke.

The purpose of this study was to determine whether applying repetitive constraint forces to the non-paretic leg during walking would induce motor learning of enhanced use of the paretic leg in individuals post-stroke. Sixteen individuals post chronic (> 6 months) stroke were recruited in this study. Each subject was tested in two conditions, i.e., applying a constraint force to the non-paretic leg during treadmill walking and treadmill walking only. For the constraint condition, subjects walked on a treadmill with no force for 1 min (baseline), with force for 7 min (adaptation), and then without force for 1 min (post-adaptation). For the treadmill only condition, a similar protocol was used but no force was applied. EMGs from muscles of the paretic leg and ankle kinematic data were recorded. Spatial-temporal gait parameters during overground walking pre and post treadmill walking were also collected. Integrated EMGs of ankle plantarflexors and hip extensors during stance phase significantly increased during the early adaptation period, and partially retained (15-21% increase) during the post-adaptation period for the constraint force condition, which were significantly greater than that for the treadmill only (3-5%) condition. The symmetry of step length during overground walking significantly improved (p = 0.04) after treadmill walking with the constraint condition, but had no significant change after treadmill walking only. Repetitively applying constraint force to the non-paretic leg during treadmill walking may lead to a motor learning of enhanced use of the paretic leg in individuals post-stroke, which may transfer to overground walking.

Gait variability following abrupt removal of external stabilization decreases with practice in incomplete spinal cord injury but increases in non-impaired individuals.

BACKGROUND: Individuals with incomplete spinal cord injury (iSCI) exhibit considerable lateral center of mass (COM) movement variability during gait transitions from a stabilizing to unassisted environment, while non-impaired individuals do not. To understand how iSCI influences gait adaption, we examined persons with and without iSCI performing repeated locomotor transitions. We hypothesized that, with practice, individuals with iSCI would prioritize COM control performance during the transition as exhibited by a reduction in kinematic variability. In, contrast, we hypothesized that non-impaired individuals would prioritize control effort by decreasing muscular activity. METHODS: Thirteen participants with iSCI and 12 non-impaired participants performed five treadmill-walking trials. During some trials, a cable-robot applied stabilizing lateral forces to the pelvis proportional in magnitude and opposite in direction to real-time lateral COM velocity. Each trial consisted of 300 continuous steps with or without a transition. During the first and last trials, no forces were applied and no transitions occurred (Null trials). During trials 2-4 (transition trials), the first 200 steps occurred in the stabilizing force field, forces were then abruptly removed, and 100 more unassisted steps were performed. We analyzed COM and step width variability, and hip abductor muscle activity during transitions (force removal until gait returned to steady state). RESULTS: Participants with iSCI displayed large COM movement variability during the first transition but reduced variability with practice. During the first transition, lateral COM speed, lateral COM excursion, and step width were all more variable than during the first Null trial (p < 0.05). By the third transition, no metric was different from Null trials (p > 0.05). In contrast, non-impaired participants' movement variability during the first transition was not different from Null trials (p > 0.05). With practice, movement variability increased: lateral COM excursion was more variable during Transitions 2 and 3 versus the first Null trial (p < 0.05). Non-impaired participants decreased hip abductor activity from Transition 1 to 3 (p < 0.05). CONCLUSIONS: Individuals with iSCI demonstrated rapid motor savings. By the third transition, individuals with iSCI reduced locomotor variability to baseline levels. In contrast, non-impaired participants prioritized control effort over control performance. With practice transitioning, non-impaired participants increased locomotor variability and decreased muscular effort.

Gradual increase of perturbation load induces a longer retention of locomotor adaptation in children with cerebral palsy.

The goal of this study is to determine whether the size and the variability of error have an impact on the retention of locomotor adaptation in children with cerebral palsy (CP). Eleven children with CP, aged 7-16 years old, were recruited to participate in this study. Three types of force perturbations (i.e., abrupt, gradual and noisy loads) were applied to the right leg above the ankle starting from late stance to mid-swing in three test sessions while the subject walked on a treadmill. Spatial-temporal gait parameters were recorded using a custom designed 3D position sensor during treadmill walking. We observed that children with CP adapted to the resistance force perturbation and showed an aftereffect consisting of increased step length after load release. Further, we observed a longer retention of the aftereffect for the condition with a gradual load than that with an abrupt load. Results from this study suggested that the size of error might have an impact on the retention of motor adaptation in children with CP with a longer retention of motor adaptation for the condition with a small size of error than that with a large error. In addition, enhanced variability of error seems facilitate motor learning during treadmill training. Results from this study may be used for the development of force perturbation based training paradigms for improving walking function in children with CP.

sEMG Based Gait Phase Recognition for Children with Spastic Cerebral Palsy.

The goal of this study was to examine the optimal strategies for the recognition of gait phase based on surface electromyogram (sEMG) of leg muscles while children with cerebral palsy (CP) walked on a treadmill. Ten children with CP were recruited to participate in this study. sEMG from eight leg muscles and leg position signals were recorded while subjects walked on a treadmill. The position signals of left and right legs were used to develop a five gait sub-phases classifier, i.e., mid stance, terminal stance, pre-swing, mid swing, and terminal swing. Seven feature sets of sEMG signals were tested in recognizing the five gait sub-phases of children with CP. Results from this study indicated that the recognition performance of mean absolute value and zero crossing was better than that with other feature sets when using support vector machine (average classification accuracy was 89.40%). Further, we found that the performance of gait phase recognition is relatively better in pre-swing than other sub-phases, and the performance of gait phase recognition is relatively poorer in mid-swing than other sub-phases. Results from this study may be used to develop an intention-driven robotic gait training system/paradigm for assisting walking in children with CP through robotic training.

Frequency and Circumstances of Falls Reported by Ambulatory Unilateral Lower Limb Prosthesis Users: A Secondary Analysis.

BACKGROUND: More than 50% of lower limb prosthesis (LLP) users report falling at least once a year, placing them at high risk for adverse health outcomes such as decreased mobility and diminished quality of life. Efforts to decrease falls in LLP users have traditionally focused on developing clinical tests to assess fall risk, designing prosthetic components to improve patient safety, and identifying risk factors to recognize potential fallers. Little attention has been directed toward recording, reporting, and characterizing the circumstances of falls in LLP users. Identifying the most common types of falls could help guide and prioritize clinical and research needs. OBJECTIVE: To characterize the frequency and circumstances of falls reported by unilateral LLP users. DESIGN: Secondary analysis of data from 2 cross-sectional studies. SETTING: Outpatient clinic and research laboratory. PARTICIPANTS: Ambulatory unilateral transtibial and transfemoral LLP users (N = 66). INTERVENTION: None. OUTCOME: A fall-type classification framework was developed based on biomechanical theory and published falls terminology. Self-reported falls and accompanying narrative descriptions of LLP users' falls in the previous 12 months were analyzed with the framework. Frequencies, estimated proportions, and estimated counts were compared across fall circumstances using 95% confidence intervals. RESULTS: Thirty-eight participants (57.6%) reported 90 falls during the previous year. All reported falls were successfully categorized using the proposed framework. Most falls occurred from disruptions to the base of support, intrinsic destabilizing factors, and a diverse set of fall patterns. Walking on level terrain was the most common activity at the time of a fall. CONCLUSION: This secondary analysis showed that falls remain frequent in ambulatory LLP users and that clinicians and researchers might wish to prioritize falls owing to disruptions of the base of support that occur while walking. Additional research with a larger sample is required to confirm and expand these results. LEVEL OF EVIDENCE: III.

Combined Visual Feedback with Pelvic Assistance Force Improves Step Length during treadmill walking in Individuals with Post-Stroke Hemiparesis.

Altered spatiotemporal gait characteristics are common impairments after stroke. Visual feedback has been used to improve spatiotemporal gait characteristics. In addition, pelvic assistance force applied in the mediolateral direction to the paretic side can improve walking pattern. Potentially, combined visual feedback and pelvic assistance force can have better rehabilitation outcomes on walking patterns. The purpose of this study was compare the effects of combined visual feedback with pelvic assistance force and visual feedback only during treadmill walking in individuals with post-stroke hemiparesis. Fifteen subjects with hemiparesis due to chronic (>6 months) stroke participated. A computer monitor placed in front of the treadmill was used to provide visual feedback on subjects' weight bearing on the paretic leg. A customized cabledriven robotic system was used to apply pelvic assistance force. The magnitude of pelvic assistance force was 9% of body weight. The session consisted of 5 sections: 1-min baseline, 7-min treadmill training (visual feedback only or combined visual feedback and pelvic assistance force), 1-min post-training (no visual feedback or pelvic assistance force), 1-min standing break, and 5-min treadmill training. The order of the visual feedback only and combined visual feedback and pelvic assistance force sessions was randomized across subjects. Spatiotemporal gait variables within the session, including stance time, single leg support time and step length, were computed. Combined visual feedback with pelvic assistance force resulted in a better improvement in step length of the paretic leg when compared to visual feedback only (p=0.03). Walking patterns after stroke could potentially be improved by applying visual feedback regrading paretic leg weight bearing and pelvic assistance force. Future study is needed to confirm the effectiveness of visual feedback for treadmill training after stroke.

Facilitating Weight Shifting During Treadmill Training Improves Walking Function in Humans With Spinal Cord Injury: A Randomized Controlled Pilot Study.

OBJECTIVE: The aim of the study was to determine whether the integration of dynamic weight shifting into treadmill training would improve the efficacy of treadmill training in humans with spinal cord injury. DESIGN: Sixteen humans with spinal cord injury were randomly assigned to receive robotic or treadmill-only training and underwent 6 wks of training. A force was applied to the pelvis for facilitating weight shifting and to the legs for assisting with leg swing for participants in the robotic group. No assistance force was applied for participants in the treadmill-only group. Outcome measures consisted of overground walking speed, 6-min walking distance, and other clinical measures and were assessed before, after 6 wks of training, and 8 wks after the end of training. RESULTS: A greater improvement in 6-min walking distance was observed after robotic training than that after treadmill-only training (P = 0.03), but there was not a significant difference between the two groups in improvements in walking speed. However, a greater improvement was observed for the participants who underwent robotic training than those who underwent treadmill-only training (i.e., 15% vs. 2%). CONCLUSIONS: Applying a pelvis assistance force for facilitating weight shifting during treadmill training may improve locomotor function in humans with spinal cord injury.

Forced Use of the Paretic Leg Induced by a Constraint Force Applied to the Nonparetic Leg in Individuals Poststroke During Walking.

BACKGROUND: Individuals with stroke usually show reduced muscle activities of the paretic leg and asymmetrical gait pattern during walking. OBJECTIVE: To determine whether applying a resistance force to the nonparetic leg would enhance the muscle activities of the paretic leg and improve the symmetry of spatiotemporal gait parameters in individuals with poststroke hemiparesis. METHODS: Fifteen individuals with chronic poststroke hemiparesis participated in this study. A controlled resistance force was applied to the nonparetic leg using a customized cable-driven robotic system while subjects walked on a treadmill. Subjects completed 2 test sections with the resistance force applied at different phases of gait (ie, early and late swing phases) and different magnitudes (10%, 20%, and 30% of maximum voluntary contraction [MVC] of nonparetic leg hip flexors). Electromyographic (EMG) activity of the muscles of the paretic leg and spatiotemporal gait parameters were collected. RESULTS: Significant increases in integrated EMG of medial gastrocnemius, medial hamstrings, vastus medialis, and tibialis anterior of the paretic leg were observed when the resistance was applied during the early swing phase of the nonparetic leg, compared with baseline. Additionally, resistance with 30% of MVC induced the greatest level of muscle activity than that with 10% or 20% of MVC. The symmetry index of gait parameters also improved with resistance applied during the early swing phase. CONCLUSION: Applying a controlled resistance force to the nonparetic leg during early swing phase may induce forced use on the paretic leg and improve the spatiotemporal symmetry of gait in individuals with poststroke hemiparesis.

Applying a pelvic corrective force induces forced use of the paretic leg and improves paretic leg EMG activities of individuals post-stroke during treadmill walking.

OBJECTIVE: To determine whether applying a mediolateral corrective force to the pelvis during treadmill walking would enhance muscle activity of the paretic leg and improve gait symmetry in individuals with post-stroke hemiparesis. METHODS: Fifteen subjects with post-stroke hemiparesis participated in this study. A customized cable-driven robotic system based over a treadmill generated a mediolateral corrective force to the pelvis toward the paretic side during early stance phase. Three different amounts of corrective force were applied. Electromyographic (EMG) activity of the paretic leg, spatiotemporal gait parameters and pelvis lateral displacement were collected. RESULTS: Significant increases in integrated EMG of hip abductor, medial hamstrings, soleus, rectus femoris, vastus medialis and tibialis anterior were observed when pelvic corrective force was applied, with pelvic corrective force at 9% of body weight inducing greater muscle activity than 3% or 6% of body weight. Pelvis lateral displacement was more symmetric with pelvic corrective force at 9% of body weight. CONCLUSIONS: Applying a mediolateral pelvic corrective force toward the paretic side may enhance muscle activity of the paretic leg and improve pelvis displacement symmetry in individuals post-stroke. SIGNIFICANCE: Forceful weight shift to the paretic side could potentially force additional use of the paretic leg and improve the walking pattern.

Motor adaptation to lateral pelvis assistance force during treadmill walking in individuals post-stroke.

The goal of this study was to determine how individuals post-stroke response to the lateral assistance force applied to the pelvis during treadmill walking. Ten individuals post chronic (> 6 months) stroke were recruited to participate in this study. A controlled assistance force (∼10% of body weight) was applied to the pelvis in the lateral direction toward the paretic side during stance of the paretic leg. Kinematics of the pelvis and legs were recorded. Applying pelvis assistance force facilitated weight shifting toward the paretic side, resulting in a more symmetrical gait pattern but also inducing an enlarged range of motion of the pelvis during early adaptation period. The neural system of individuals post stroke adapted to the pelvis assistance force and showed an aftereffect consists of reduced range of motion of the pelvis following load release during post adaptation period.

Robotic Resistance Treadmill Training Improves Locomotor Function in Children With Cerebral Palsy: A Randomized Controlled Pilot Study.

OBJECTIVE: To determine whether applying controlled resistance forces to the legs during the swing phase of gait may improve the efficacy of treadmill training as compared with applying controlled assistance forces in children with cerebral palsy (CP). DESIGN: Randomized controlled study. SETTING: Research unit of a rehabilitation hospital. PARTICIPANTS: Children with spastic CP (N=23; mean age, 10.6y; range, 6-14y; Gross Motor Function Classification System levels, I-IV). INTERVENTIONS: Participants were randomly assigned to receive controlled assistance (n=11) or resistance (n=12) loads applied to the legs at the ankle. Participants underwent robotic treadmill training 3 times a week for 6 weeks (18 sessions). A controlled swing assistance/resistance load was applied to both legs starting from the toe-off to mid-swing phase of gait during training. MAIN OUTCOME MEASURES: Outcome measures consisted of overground walking speed, 6-minute walk distance, and Gross Motor Function Measure scores and were assessed pre and post 6 weeks of training and 8 weeks after the end of training. RESULTS: After 6 weeks of treadmill training in participants from the resistance training group, fast walking speed and 6-minute walk distance significantly improved (18% and 30% increases, respectively), and 6-minute walk distance was still significantly greater than that at baseline (35% increase) 8 weeks after the end of training. In contrast, overground gait speed and 6-minute walk distance had no significant changes after robotic assistance training. CONCLUSIONS: The results of the present study indicated that robotic resistance treadmill training is more effective than assistance training in improving locomotor function in children with CP.

Effects of the Integration of Dynamic Weight Shifting Training Into Treadmill Training on Walking Function of Children with Cerebral Palsy: A Randomized Controlled Study.

OBJECTIVE: The aim of the study was to determine whether applying an assistance force to the pelvis and legs during treadmill training can improve walking function in children with cerebral palsy. DESIGN: Twenty-three children with cerebral palsy were randomly assigned to the robotic or treadmill only group. For participants who were assigned to the robotic group, a controlled force was applied to the pelvis and legs during treadmill walking. For participants who were assigned to the treadmill only group, manual assistance was provided as needed. Each participant trained 3 times/wk for 6 wks. Outcome measures included walking speed, 6-min walking distance, and clinical assessment of motor function, which were evaluated before, after training, and 8 wks after the end of training, and were compared between two groups. RESULTS: Significant increases in walking speed and 6-min walking distance were observed after robotic training (P = 0.03), but no significant change was observed after treadmill training only. A greater increase in 6-min walking distance was observed after robotic training than that after treadmill only training (P = 0.01). CONCLUSIONS: Applying a controlled force to the pelvis and legs, for facilitating weight-shift and leg swing, respectively, during treadmill training may improve walking speed and endurance in children with cerebral palsy. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) discuss the importance of physical activity at the participation level (sports programs) for children with cerebral palsy; (2) contrast the changes in walking ability and endurance for children in GMFCS level I, II and III following sports programs; and (3) identify the impact of higher frequency of sports program attendance over time on walking ability. LEVEL: Advanced ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 0.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Kinematic and EMG Responses to Pelvis and Leg Assistance Force during Treadmill Walking in Children with Cerebral Palsy.

Treadmill training has been used for improving locomotor function in children with cerebral palsy (CP), but the functional gains are relatively small, suggesting a need to improve current paradigms. The understanding of the kinematic and EMG responses to forces applied to the body of subjects during treadmill walking is crucial for improving current paradigms. The objective of this study was to determine the kinematics and EMG responses to the pelvis and/or leg assistance force. Ten children with spastic CP were recruited to participate in this study. A controlled assistance force was applied to the pelvis and/or legs during stance and swing phase of gait through a custom designed robotic system during walking. Muscle activities and spatial-temporal gait parameters were measured at different loading conditions during walking. In addition, the spatial-temporal gait parameters during overground walking before and after treadmill training were also collected. Applying pelvis assistance improved step height and applying leg assistance improved step length during walking, but applying leg assistance also reduced muscle activation of ankle flexor during the swing phase of gait. In addition, step length and self-selected walking speed significantly improved after one session of treadmill training with combined pelvis and leg assistance.

Repeat Exposure to Leg Swing Perturbations During Treadmill Training Induces Long-Term Retention of Increased Step Length in Human SCI: A Pilot Randomized Controlled Study.

OBJECTIVE: To determine whether repeat exposure to force perturbations during treadmill training can induce long-term retention of improved step length and overall improvements in locomotor function in persons with spinal cord injury. DESIGN: Fourteen patients with spinal cord injury were recruited and randomly assigned to swing resistance or swing assistance training groups. A controlled swing resistance or assistance force, for resistance or assistance training groups, respectively, was applied to both legs through a cable-driven robotic system during treadmill training. Each participant trained 3 times per week for 6 weeks. Step length, walking speed, 6-minute walking distance, and other clinical assessments were evaluated before and after 6 weeks of training and 8 weeks after the end of training. RESULTS: A significant increase in step length was observed after 6 weeks of resistance training (P = 0.04). Step length tended to increase after assistance treadmill training, but the change was not significant (P = 0.18). The changes in step length and functional gains had no significant difference between 2 groups. CONCLUSIONS: Repeat exposure to swing resistance during treadmill training may induce a prolonged retention of increased step length, although it remains unclear whether swing resistance versus assistance is more effective in inducing increased step length.

Robotic resistance/assistance training improves locomotor function in individuals poststroke: a randomized controlled study.

OBJECTIVE: To determine whether providing a controlled resistance versus assistance to the paretic leg at the ankle during treadmill training will improve walking function in individuals poststroke. DESIGN: Repeated assessment of the same patients with parallel design and randomized controlled study between 2 groups. SETTING: Research units of rehabilitation hospitals. PARTICIPANTS: Patients (N=30) with chronic stroke. INTERVENTION: Subjects were stratified based on self-selected walking speed and were randomly assigned to the resistance or assistance training group. For the resistance group, a controlled resistance load was applied to the paretic leg at the ankle to resist leg swing during treadmill walking. For the assistance group, a load that assists swing was applied. MAIN OUTCOME MEASURES: Primary outcome measures were walking speed and 6-minute walking distance. Secondary measures included clinical assessments of balance, muscle tone, and quality of life. Outcome measures were evaluated before and after 6 weeks of training and at 8 weeks' follow-up, and compared within group and between the 2 groups. RESULTS: After 6 weeks of robotic training, walking speed significantly increased for both groups, with no significant differences in walking speed gains observed between the 2 groups. In addition, 6-minute walking distance and balance significantly improved for the assistance group but not for the resistance group. CONCLUSIONS: Applying a controlled resistance or an assistance load to the paretic leg during treadmill training may induce improvements in walking speed in individuals poststroke. Resistance training was not superior to assistance training in improving locomotor function in individuals poststroke.