The pilot study of the effect of six-week robot-assisted ankle training on mobility and strength of lower extremity and life habits for children with cerebral palsy.

Background: Children with cerebral palsy often have weak ankle muscles and reduced ankle dorsiflexion, which leads to activity limitations and eventually affects quality of life. Robotic ankle training was recently developed to facilitates muscle function through a high repetition of exercises. This study investigated the effect of six-week ankle training using the Anklebot device to improve lower limb structural and functional impairments and the resulting impact on quality of life. Methods: Five children with spastic cerebral palsy aged between 4 and 11 years participated in six weeks of bilateral ankle assistive training using the Anklebot device. All lower limb muscle strength was measured with a hand-held dynameter, and range of motion was measured with a goniometer, at four different time points. Muscle architecture was assessed using a portable diagnostic ultrasound device, and quality of life was assessed using the Life Habits for Children scale, at two points in time only. Results: Muscle strength and range of motion for all lower limb joints demonstrated significant improvement on both sides after training. The ankle muscle architecture showed non-significant improvement, while an overall significant improvement in the total score of the Life Habits for Children scale was detected after training. Conclusion: Robot-assisted task-specific ankle training provides promising effects by allowing the required repetition to improve structural and functional muscle and joint impairments, which has a positive influence on the children's quality of life. However, due to a limited sample size, these results should be considered as preliminary; further study is needed.

Examination of sustained gait speed during extended walking in individuals with chronic stroke.

OBJECTIVES: To determine if individuals with chronic stroke were able to sustain their peak gait speed during the 6-minute walk test (6MWT), and to explore this sustainability across community ambulation potential subgroups. DESIGN: Prospective cross-sectional study. SETTING: University-based research laboratory, hospitals, and stroke support groups. PARTICIPANTS: A sample of individuals with chronic stroke (N=48) completed a series of questionnaires and physical outcome measures, including gait mat assessment, during a single visit. INTERVENTIONS: Not applicable; 1-time cross-sectional data collection. MAIN OUTCOME MEASURES: During the 6MWT, we measured peak gait speed and end gait speed to assess sustainability, along with beginning gait speed, total distance walked, and rating of perceived exertion. We also assessed maximum gait speed during the 10-meter walk test (10MWT). Finally, we examined these gait outcomes across the subgroups. RESULTS: During the 6MWT, peak gait speed declined from .89m/s (SD=.38) to an end speed of .82m/s (SD=.36), whereas perceived exertion increased from 7.7 (SD=2.6) to 11.8 (SD=3.6). This peak gait speed was slower than the 10MWT maximum speed of 1.06m/s (SD=.51), but faster than the 6MWT beginning speed of .81m/s (SD=.34). The unlimited community ambulator subgroup was the primary contributor to sustainability differences. CONCLUSIONS: Predicting community ambulation potential based on the discrete gait speed from the 10MWT and endurance based on the average from the 6MWT might be incomplete if gait speed sustainability is not also assessed.

Fatigue and pain: relationships with physical performance and patient beliefs after stroke.

BACKGROUND: Fatigue and pain are common after stroke, potentially impacting stroke recovery. OBJECTIVE: This study examines the frequency and impact of fatigue and pain in people with chronic stroke. METHOD: Seventy-seven people with chronic stroke completed a one-time assessment consisting of a battery of self-report and performance tools to describe and quantify mobility issues post stroke. We assessed the proportion of individuals with fatigue and pain and the relationship between fatigue and pain and other variables including gait (10-meter walk and 6-minute walk test), balance (Berg Balance Scale), activity and participation (ICF Measure of Participation and Activities), chronic disease self-efficacy (Chronic Disease Self-Efficacy Scale), and balance self-efficacy (Activity-Specific Balance Confidence Scale). Additionally, subgroup comparisons were made between participants with and without coexisting fatigue and pain. RESULTS: Fatigue and pain were reported by 66% and 45% of study participants, respectively. Thirty-four percent of the sample reported co-existing fatigue and pain. Participants with coexisting fatigue and pain demonstrated significantly lower chronic disease and balance self-efficacy and decreased activity than participants without coexisting fatigue and pain. Individually, fatigue correlated with balance, chronic disease self-efficacy, balance self-efficacy, activity, and participation, whereas pain correlated with chronic disease self-efficacy, balance self-efficacy, and activity. CONCLUSION: Fatigue and pain are common after stroke and are negatively correlated with outcomes important to rehabilitation. Efforts focused on examining the impact of interventions on fatigue and pain are warranted. It is possible that changes to these body structure limitations could positively impact functional recovery and community re-entry after stroke.

Poststroke balance improves with yoga: a pilot study.

BACKGROUND AND PURPOSE: Balance impairment is common after stroke; modified yoga may be able to improve balance and other important poststroke variables. Scientific-evidence is needed to support such treatment interventions. The purpose of this study was to assess the impact of a yoga-based rehabilitation intervention on balance, balance self-efficacy, fear of falling (FoF), and quality of life after stroke. METHODS: This was a prospective, randomized, pilot study of yoga-based rehabilitation for people with chronic stroke. All yoga sessions were taught by a registered yoga therapist, occurred twice per week for 8 weeks and included seated, standing, and floor postures with relaxation and meditation. Balance was assessed with the Berg Balance Scale, balance self-efficacy with the Activities-specific Balance Confidence Scale, FoF with a dichotomous yes/no question, and quality of life with the Stroke Specific Quality of Life scale. RESULTS: There were no significant differences between wait-list control (n=10) and yoga (n=37) groups in baseline or follow-up scores. However, using within-group comparisons, yoga group data demonstrated significant improvement in balance (Berg Balance Scale, 41.3±11.7 vs 46.3±9.1; P<0.001) and FoF (51% vs 46% with FoF; P<0.001). CONCLUSIONS: A group yoga-based rehabilitation intervention for people with chronic stroke has potential in improving multiple poststroke variables. Group yoga may be complementary to rehabilitation, may be possible in medical-based and community-based settings, and may be cost-effective. Further testing of group yoga-based rehabilitation interventions is warranted. Clinical Trial Registration- URL: http://clinicaltrials.gov. Unique Identifier: NCT01109602.

Balance and balance self-efficacy are associated with activity and participation after stroke: a cross-sectional study in people with chronic stroke.

OBJECTIVES: To (1) examine the relationships between multiple poststroke mobility variables (gait speed, walking capacity, balance, balance self-efficacy, and falls self-efficacy) and activity and participation; and (2) determine which poststroke mobility variables are independently associated with activity and participation. DESIGN: This is the primary analysis of a prospective cross-sectional study completed to understand the impact of mobility on activity and participation in people with chronic stroke. SETTING: University-based research laboratory, hospitals, and stroke support groups. PARTICIPANTS: People (N=77) with stroke greater than 6 months ago were included in the study if they were referred to occupational or physical therapy for physical deficits as a result of the stroke, completed all stroke related inpatient rehabilitation, had residual functional disability, scored a ≥4 out of 6 on the short, 6-item Mini-Mental State Examination, and were between the ages of 50 and 85. INTERVENTIONS: Not applicable, this is a cross-sectional data collection of 1 timepoint. MAIN OUTCOME MEASURES: We measured activity and participation with the validated International Classification of Functioning, Disability and Health Measure of Participation and Activities. Other variables included gait speed (10-meter walk), walking capacity (6-minute walk), balance (Berg Balance Scale), balance self-efficacy (Activities Specific Balance Confidence Scale), and falls self-efficacy (Modified Falls Efficacy Scale). RESULTS: Only balance self-efficacy was found to be independently associated with poststroke activity (ß=-.430, P<.022, 95% confidence interval [CI], -.247 to -.021) and participation (ß=-.439, P<.032, 95% CI, -.210 to -.010). CONCLUSIONS: Among people with chronic stroke, balance self-efficacy, not physical aspects of gait, was independently associated with activity and participation. While gait training continues to be important, this study indicates a need to further evaluate and address the psychological factors of balance and falls self-efficacy to obtain the best stroke recovery.

Plantar pressure during running in subjects with chronic ankle instability.

BACKGROUND: It has been suggested that dynamic foot and ankle mechanics predispose individuals with CAI to repetitive episodes of the ankle ``giving way.'' Plantar pressure variations during a walking gait have been detected in those with CAI, but more dynamic conditions for analysis are needed. The purpose of this study was to evaluate plantar pressure distributions during a running gait in individuals with CAI, individuals who suffered a lateral ankle sprain, but did not develop CAI (AS), and subjects with no history of a lateral ankle sprain (CON). MATERIALS AND METHODS: Forty-five subjects [15 in each group, healthy males (18) and females (27), age 18 to 45] were recruited from University communities to participate in this study. Plantar pressure distributions were analyzed on a Tekscan© plantar pressure mat at 66 frames per second during a running gait at a controlled speed. The following variables were obtained: rearfoot medial/lateral (M/L) pressure ratio at foot strike (FS) and center-of-pressure (COP) trajectory during the initial loading response (heel strike to initial peak GRF). Separate one-way ANOVA with Tukey's post-hoc were used to test for group differences. The significance level was defined as p < 0.05. RESULTS: The CAI group had a significantly more lateral ratio (0.97 ± 0.12) at FS when compared to the CON (1.01 ± 0.13) and AS (1.11 ± 0.13) groups. The CAI subjects had a lateral COP trajectory during the loading phase (7.97 degrees ± 11.02), while both the AS (-3.68 degrees ± 10.24) and CON groups (-6.27 degrees ± 9.86) had medial trajectories. The difference was significant between the CAI group and both the AS and CON groups (all significant {\it p} values were less than 0.05). CONCLUSION: Our results confirm that CAI subjects have a more lateral foot positioning and loading pattern during a barefoot running gait when compared to both the CON and LAS groups. CLINICAL RELEVANCE: Clinicians treating patients with CAI should consider providing interventions to decrease the amount of rearfoot inversion at FS and during loading in order to create a more medial COP trajectory upon impact.

Proximal and distal influences on hip and knee kinematics in runners with patellofemoral pain during a prolonged run.

STUDY DESIGN: Cross-sectional experimental laboratory study. OBJECTIVES: To investigate the relationships between hip strength and hip kinematics, and between arch structure and knee kinematics during prolonged treadmill running in runners with and without patellofemoral pain syndrome (PFPS). BACKGROUND: Hip weakness can lead to excessive femoral motions that adversely affect patellofemoral joint mechanics. Similarly, foot mechanics, which are influenced by foot structure, are also known to influence patellofemoral joint mechanics. Thus, proximal and distal factors should be considered when studying individuals with PFPS. METHODS AND MEASURES: Twenty recreational runners with PFPS (5 male, 15 female) and 20 matched uninjured runners participated in the study. Hip abduction and hip external rotation isometric strength measurements were collected before and after a prolonged run, while the arch height index was recorded on all runners before the run. Lower extremity kinematic data were collected at the beginning and end of the run. Two-way repeated-measures analyses of variance (ANOVAs) were used for analysis. RESULTS: Both groups displayed decreases in hip abductor and external rotator strengths at the end of the run. The PFPS group displayed significantly lower hip abduction strength [(kg x cm)/body mass] compared to controls (PFPS group: begin 15.3, end 13.5; uninjured group: begin 17.3, end 15.4). At the end of the run, the level of association between hip abduction strength and the peak hip adduction angle for the PFPS group was statistically significant, indicating a strong relationship (r = -0.74). No other associations with hip strength were observed in either group. Arch height did not differ between groups and no significant association was observed between arch height and peak knee adduction angle during running. CONCLUSIONS: Runners with PFPS displayed weaker hip abductor muscles that were associated with an increase in hip adduction during running. This relationship became more pronounced at the end of the run. LEVEL OF EVIDENCE: Therapy, level 5.

Discrete and continuous joint coupling relationships in uninjured recreational runners.

BACKGROUND: Abnormal joint coupling is thought to be related to overuse injuries in runners. However, researchers do not yet know what constitutes normal joint coupling during running, which makes abnormal coupling difficult to define. METHODS: Lower extremity kinematics were collected from 40 recreational runners during stance. Joint coupling methods were applied and, for each method, means and both within- and between-subject variability were calculated. The 95% confidence interval was used to compare differences across coupling relationships and periods of stance. FINDINGS: Timing between rearfoot eversion, tibial internal rotation, and knee flexion were relatively synchronous while relationships involving knee internal rotation were more asynchronous. The excursion ratios showed that every 2 degrees of rearfoot eversion was coupled with 1 degrees of both tibial internal rotation and knee internal rotation. Vector coding results showed that just beyond maximum loading, all joint coupling relationships resulted in relatively equal amounts of motion, while the within-subject variability was similar throughout stance. The continuous relative phase results showed that the most out-of-phase coupling occurred in the periods around heel-strike and toe-off while the most in-phase coupling occurred in the period just beyond maximum loading of the leg. The continuous relative phase within-subject variability was greatest at the periods around heel-strike and toe-off and smallest just beyond maximum loading. INTERPRETATION: With a better understanding of joint coupling in uninjured runners, these data will help to serve as a reference for future studies investigating the relationship between running injuries and abnormal joint coupling.

Lower extremity joint coupling during running: a current update.

BACKGROUND: The relationship between lower extremity mechanics and injury is not well understood. However, joint coupling studies are beginning to emerge, which may lend further insight into running biomechanics. PURPOSE: To provide a current review of the research examining lower extremity joint coupling in running. SUMMARY: There are various techniques utilized to measure joint coupling, including joint timing, rearfoot eversion/tibial internal rotation ratios, continuous relative phase calculations, and vector coding. The study of joint coupling is of particular interest as it may pertain to running injuries. There is some evidence that joint coupling may be altered with orthotics and/or with footwear. Most studies have included a relatively small sample size and larger scale studies are needed to quantify normal ranges for many of the coupling measures. In addition, prospective studies are needed to clarify the relationship to injury. RELEVANCE: It is hoped that this update will serve as a review of the current state of thought regarding lower extremity joint coupling during running. As greater insight into the role of joint coupling in injuries is gained, more optimal intervention and prevention strategies can be developed to minimize injury risk.

The effect of random or sequential presentation of targets during robot-assisted therapy on children.

BACKGROUND: Robot assisted upper extremity therapy has been shown to be effective in adult stroke patients and in children with cerebral palsy (CP) and other acquired brain injuries (ABI). The patient's active involvement is a factor in its efficacy. However, this demands focused attention during training sessions, which can be a challenge for children. OBJECTIVE: To compare results of training requiring two different levels of focused attention. Differences in short term performance and retention of gains as a function of training protocol as measured by the Fugl-Meyer (FM) were predicted. METHODS: Thirty-one children with CP or ABI were randomly divided into two groups. All received 16 one hour sessions of robot-assisted therapy (twice a week for 8 weeks) where they moved a robot handle to direct a cursor on the screen toward designated targets. One group had targets presented sequentially in clockwise fashion, the other presented in random order. Thus, one group could anticipate the position of each target, the other could not. RESULTS: Both groups showed significant functional improvement after therapy, but no significant difference between groups was observed. CONCLUSIONS: Assist-as-needed robotic training is effective in children with CP or ABI with small non-significant differences attributed to attentional demand.

Foot kinematics and loading of professional athletes in American football-specific tasks.

The purpose of this study was to describe stance foot and ankle kinematics and the associated ground reaction forces at the upper end of human performance in professional football players during commonly performed football-specific tasks. Nine participants were recruited from the spring training squad of a professional football team. In a motion analysis laboratory setting, participants performed three activities used at the NFL Scouting Combine to assess player speed and agility: the 3-cone drill, the shuttle run, and the standing high jump. The talocrural and first metatarsophalangial joint dorsiflexion, subtalar joint inversion, and the ground reaction forces were determined for the load bearing portions of each activity. We documented load-bearing foot and ankle kinematics of elite football players performing competition-simulating activities, and confirmed our hypothesis that the talocrural, subtalar, and metatarsophalangeal joint ranges of motion for the activities studied approached or exceeded reported physiological limits.

Is walking faster or walking farther more important to persons with chronic stroke?

PURPOSE: The purposes of this mixed-methods study were to (1) investigate whether walking faster or walking farther was more important for getting "out and about" to persons with chronic stroke and (2) explore explanations for walking preferences. METHOD: A convenience sample of 77 adults with chronic stroke completed questionnaires and walking outcomes in one visit. Participants were asked whether walking faster or farther was more important to them for getting "out and about", and differences between response groups (faster vs. farther) were evaluated. Participants also described their preference for walking faster or farther. Qualitative responses were analyzed using content analysis. RESULTS: The majority of participants (76%; n = 58) reported walking farther was more important, while 18% (n = 14) reported walking faster was more important. Statistically significant differences were not found between response groups for any variable. Primary themes identified from participant preferences for walking faster included: (1) faster speed equals better walking ability and (2) getting places faster/quicker. Primary themes from preferences for walking farther included: (1) engaging in activity and participation within home and community; (2) walking farther at a slower pace; and (3) fatigue with walking. CONCLUSIONS: Individual preferences for walking faster versus walking farther by persons with chronic stroke should be considered by clinicians when making decisions for rehabilitation. IMPLICATIONS FOR REHABILITATION: • Individual preferences for walking faster versus walking farther by patients with chronic stroke should be considered by rehabilitation clinicians when making decisions about examination and intervention. • The majority of participants with chronic stroke in this study indicated the importance of walking farther in order to better engage in activities both at home and away from home. • Interventions that focus on improving endurance and energy conservation may need to be used for persons with chronic stroke who want to walk father in order to maximize their potential for walking longer distances.

Lower extremity kinematics in runners with patellofemoral pain during a prolonged run.

PURPOSE: Investigate lower extremity kinematics in runners with patellofemoral pain (PFP) syndrome during a prolonged run. METHODS: For this study, 20 runners with PFP and 20 uninjured controls performed a prolonged run on a treadmill at a self-selected pace. The run ended based on HR, perceived exertion, or level of knee pain. Kinematic data were analyzed at the beginning and at the end of the run. RESULTS: The PFP group demonstrated less peak knee flexion, peak hip adduction, eversion excursion, peak knee flexion velocity, peak hip adduction velocity, and peak hip internal rotation velocity compared with controls. A significant main effect for time indicated that increases in most kinematic variables occurred at the end of the run. Interestingly, five runners with PFP displayed atypical motions of knee valgus and eight displayed hip abduction during the first half of stance. CONCLUSIONS: The PFP group as a whole displayed less overall motion compared with controls. This may be indicative of a strategy aimed at limiting lower extremity movement to reduce pain. However, increases in joint motion occurred at the end of the run where pain levels were greatest. Three distinct PFP subgroups were noted, and each demonstrated unique kinematic mechanisms that may be associated with PFP. In the knee valgus subgroup, increased knee valgus and decreased peak motions were noted in other joints. In the hip abduction subgroup, less knee flexion and motion overall was noted. In the subgroup that displayed typical first half patterns (knee and hip adduction), increased hip internal rotation and decreased knee internal rotation were observed. These results suggest that several different kinematic mechanisms related to PFP may exist.

The effects of running in an exerted state on lower extremity kinematics and joint timing.

Runners rarely run to the point of maximum fatigue or exhaustion. However, no studies have investigated how the level of exertion associated with a typical running session influences running mechanics. The purpose of this study was to investigate the effects that running in an exerted state had on the kinematics and joint timing within the lower extremity of uninjured, recreational runners. Twenty runners performed a prolonged treadmill run at a self-selected pace that best represented each runner's typical training run. The run ended based on heart rate or perceived exertion levels that represented a typical training run. Kinematics and joint timing between the foot, knee, and hip were analyzed at the beginning and end of the run. Increases were primarily observed at the end of the run for the peak angles, excursions, and peak velocities of eversion, tibial internal rotation, and knee internal rotation. No differences were observed for knee flexion, hip internal rotation, or any joint timing relationship. Based on these results, runners demonstrated subtle changes in kinematics in the exerted state, most notably for eversion. However, runners were able to maintain joint timing throughout the leg, which may have been a function of the knee. Thus, uninjured runners normally experience small alterations in kinematics when running with typical levels of exertion. It remains unknown how higher levels of exertion influence kinematics with joint timing and the association with running injuries, or how populations with running injuries respond to typical levels of exertion.

Effects of varying amounts of pronation on the mediolateral ground reaction forces during barefoot versus shod running.

Despite extensive research on running mechanics, there is still a knowledge gap with respect to the degree of relationship between mediolateral ground reaction forces (ML-GRF) and foot pronation. Our goal was to investigate whether differences exist in ML-GRF among runners that exhibit different degrees of pronation. Seventeen male and 13 female recreational runners ran with and without shoes while ML-GRF and frontal kinematics were collected simultaneously. Subjects were divided into groups based upon their peak eversion (low pronation, middle pronation, high pronation). Discrete parameters from the ML-GRF were peak forces, respective times of occurrence, and impulses. No significant differences were found between groups regarding the magnitude of ML-GRF. Based upon the relative times of occurrence, the peak medial GRF occurred closer to the peak eversion than the peak lateral GRF. Findings support the idea that the ML-GRF have less to do with pronation than previous research suggested.