Exploiting telerobotics for sensorimotor rehabilitation: a locomotor embodiment.

BACKGROUND: Manual treadmill training is used for rehabilitating locomotor impairments but can be physically demanding for trainers. This has been addressed by enlisting robots, but in doing so, the ability of trainers to use their experience and judgment to modulate locomotor assistance on the fly has been lost. This paper explores the feasibility of a telerobotics approach for locomotor training that allows patients to receive remote physical assistance from trainers. METHODS: In the approach, a trainer holds a small robotic manipulandum that shadows the motion of a large robotic arm magnetically attached to a locomoting patient's leg. When the trainer deflects the manipulandum, the robotic arm applies a proportional force to the patient. An initial evaluation of the telerobotic system's transparency (ability to follow the leg during unassisted locomotion) was performed with two unimpaired participants. Transparency was quantified by the magnitude of unwanted robot interaction forces. In a small six-session feasibility study, six individuals who had prior strokes telerobotically interacted with two trainers (separately), who assisted in altering a targeted gait feature: an increase in the affected leg's swing length. RESULTS: During unassisted walking, unwanted robot interaction forces averaged 3-4 N (swing-stance) for unimpaired individuals and 2-3 N for the patients who survived strokes. Transients averaging about 10 N were sometimes present at heel-strike/toe-off. For five of six patients, these forces increased with treadmill speed during stance (R2 = .99; p < 0.001) and increased with patient height during swing (R2 = .71; p = 0.073). During assisted walking, the trainers applied 3.0 ± 2.8 N (mean ± standard deviation across patients) and 14.1 ± 3.4 N of force anteriorly and upwards, respectively. The patients exhibited a 20 ± 21% increase in unassisted swing length between Days 1-6 (p = 0.058). CONCLUSIONS: The results support the feasibility of locomotor assistance with a telerobotics approach. Simultaneous measurement of trainer manipulative actions, patient motor responses, and the forces associated with these interactions may prove useful for testing sensorimotor rehabilitation hypotheses. Further research with clinicians as operators and randomized controlled trials are needed before conclusions regarding efficacy can be made.

Visuomotor control of ankle joint using position vs. force.

Ankle joint plays a critical role in daily activities involving interactions with environment using force and position control. Neuromechanical dysfunctions (e.g., due to stroke or brain injury), therefore, have a major impact on individuals' quality of life. The effective design of neuro-rehabilitation protocols for robotic rehabilitation platforms relies on understanding the control characteristics of the ankle joint in interaction with external environment using force and position, as the findings in upper limb may not be generalizable to the lower limb. This study aimed to characterize the skilled performance of ankle joint in visuomotor position and force control. A two-degree-of-freedom (DOF) robotic footplate was used to measure individuals' force and position. Healthy individuals (n = 27) used ankle force or position for point-to-point and tracking control tasks in 1-DOF and 2-DOF virtual game environments. Subjects' performance was quantified as a function of accuracy and completion time. In contrast to comparable performance in 1-DOF control tasks, the performance in 2-DOF tasks was different and had characteristic patterns in the position and force conditions, with a significantly better performance for position. Subjective questionnaires on the perceived difficulty matched the objective experimental results, suggesting that the poor performance in force control was not due to experimental set-up or fatigue but can be attributed to the different levels of challenge needed in neural control. It is inferred that in visuomotor coordination, the neuromuscular specialization of ankle provides better control over position rather than force. These findings can inform the design of neuro-rehabilitation platforms, selection of effective tasks and therapeutic protocols.

Between-side differences in hand-grip strength across the age span: Findings from 2011-2014 NHANES and 2011 NIH Toolbox studies.

This project was undertaken to describe percentage differences in the grip strength between the dominant and nondominant-sides of left- and right-handed males and females across the age span. Data used in the project were from population-based samples of participants: 13,653 from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) and 3,571 from the 2011 normative phase of the National Institutes of Health (NIH) Toolbox project. Depending on how percentage differences were calculated, the overall grip strength was a mean 5.0-5.6% greater on the dominant than nondominant side. The percentage differences were significantly greater for individuals who were right-hand dominant rather than left-hand dominant. The differences also varied according to gender. We present summary data for percentage differences stratified by study, handedness, and gender. The values can be used to determine whether grip strength on one side is limited relative to the other.

Summary of grip strength measurements obtained in the 2011-2012 and 2013-2014 National Health and Nutrition Examination Surveys.

STUDY DESIGN: Cross-sectional and descriptive study. INTRODUCTION: Supported by the Centers for Disease Control and Prevention, the National Health and Nutrition Examination Survey (NHANES) began collecting grip strength data from nationally representative samples in 2011. PURPOSE OF THE STUDY: To examine the stability of the grip strength values across 2 data release cycles and provide updated US population-based grip strength values for 6 to 80 year olds. METHODS: Handgrip data from 13,676 participants aged 6-80 years were extracted from the NHANES 2011-2014 database. The muscle strength/grip test component measured the isometric grip strength using a Takei digital handgrip dynamometer (Takei Scientific Instruments, Shinagawa-Ku, Tokyo). Grip strength values (best of 3 trials for each hand) were summarized by gender, dominant side, and age group. Grip data from 2 data release cycles (2011-2012 vs 2013-2014) were compared. RESULTS: Differences between 2 data release cycles were negligible. Hence, we summarize grip strength values across the entire 2011-2014 period. The mean grip strength ranged from 50.3 kg for the dominant hand of 30- to 34-year-old men to 10.0 kg for the nondominant hand of 6-year-old girls. DISCUSSION: The summary data we present provide relatively current reference values to which tested individuals can be compared. However, clinicians and/or researchers should be aware that the instrumentation and procedures may influence the values. CONCLUSIONS: Results supported the stability of the NHANES grip strength values across data release cycles.

Handgrip Strength: A Comparison of Values Obtained From the NHANES and NIH Toolbox Studies.

IMPORTANCE: Handgrip dynamometry is probably the most commonly used method to characterize overall human muscle strength. OBJECTIVE: To compare and summarize grip strength measurements obtained from two population-based studies. DESIGN: Secondary data analysis. SETTING AND PARTICIPANTS: Data from (1) the 2011-2014 National Health and Nutrition Examination Survey (NHANES) with 13,918 participants and (2) the 2011 normative phase of the National Institutes of Health (NIH) Toolbox project with 3,594 participants. OUTCOMES AND MEASURES: The NHANES values used were the mean and best of three trials; the NIH Toolbox value used was the one maximum trial after a practice trial. RESULTS: General linear model analysis revealed that values obtained from the NIH Toolbox differed from NHANES best values but not from NHANES mean values. The analysis also indicated, regardless of the values used, that grip strength differed significantly between dominant and nondominant sides, males and females, and age groups. We provide updated reference values for handgrip strength. CONCLUSIONS AND RELEVANCE: On the basis of these analyses, we summarize grip strength measures obtained from the NHANES and NIH Toolbox for side, gender, and age group strata. Reference values are essential to assist in the interpretation of testing results and clinical decision making.

Assessing manual dexterity: Comparing the WorkAbility Rate of Manipulation Test with the Minnesota Manual Dexterity Test.

STUDY DESIGN: Cross-sectional study. INTRODUCTION: The WorkAbility Rate of Manipulation Test (WRMT), an adaptation of the Minnesota Manual Dexterity Test (MMDT), contains a revised board and protocols to improve its utility for therapy or fitness assessment. PURPOSE OF THE STUDY: To describe the development and preliminary psychometric properties of WRMT. METHODS: Sixty-six healthy participants completed MMDT and WRMT in a random order followed by a user experience survey. We compared tests using repeated-measures analysis of variance, test-retest reliability, and examined agreement between tests. RESULTS: Despite the similarities of these 2 instruments, the different administration protocols resulted in statistically different score distributions (P < .001). Results supported good test-retest reliability of WRMT (placing test ICC = 0.88-0.90 and turning test ICC = 0.68-0.82). The WRMT correlated moderately with MMDT (r = 0.81 in placing test and r = 0.44-0.57 in turning test). Bland-Altman plot showed that the differences in completion time were 3.8 seconds between placing tests and 19.6 (both hands), 0.3 (right hand), and 3.9 (left hand) seconds between turning tests. Overall, participants felt that the instruction of WRMT was easier to follow (44%) and preferred its setup, color, and depth of the test board (49%). Time required to complete 1 panel of 20 disks correlated highly with the time needed to finish a complete trial of 60 disks in both MMDT (r = 0.91-0.97) and WRMT (r = 0.88-0.95). CONCLUSIONS: Caution is warranted in comparing scores from these 2 test variants. LEVEL OF EVIDENCE: 3b.

Muscle activation pattern during self-propelled treadmill walking.

[Purpose] To examine muscular demands during self-propelled treadmill walking to provide a potential option for fitness training. [Participants and Methods] Eleven healthy college students were recruited. Participants walked under three conditions: over-ground walking at a self-selected speed, treadmill walking at a self-selected speed, and treadmill walking at a speed comparable to that of over-ground walking. Step lengths and lower extremity muscle activations were recorded while participants walked under the three conditions. [Results] Step lengths were significantly shorter when participants walked on a self-propelled treadmill than when walking over-ground. The spatiotemporal and muscle activations of the gaits varied among the different walking conditions. Muscular demands at the moment of heel-strike were higher around the hip and knee when walking on the self-propelled treadmill than when walking over-ground. [Conclusion] During heel-strike, the lower extremity extensors were activated more on the self-propelled treadmill with an incline, especially at faster speeds, than during over-ground walking. A low-cost, self-propelled treadmill may be a modality for training specific muscles.

Alteration of ankle kinematics and muscle activity during heel contact when walking with external loading.

PURPOSE: The risk of recurrent ankle sprains could be reduced if the ankle joint is positioned in a more closed pack position (eversion and dorsiflexion) with enhanced co-activation of Tibialis Anterior (TA) and Peroneus Longus (PL) around heel contact in walking. We examined whether such alteration can be induced by augmenting ankle position error in the inversion and plantarflexion directions. METHODS: Fifteen young, healthy subjects participated in this study. They walked on a treadmill while a light weight was affixed to the dorsal-lateral side of the test foot to create afferent error signals in the inversion and plantarflexion directions. We recorded and analyzed subjects' ankle kinematics and electromyographic (EMG) activity of TA and PL before (baseline), during (adaptation), and after (post adaptation) walking with the weight. Our analyses focused on 30 ms before and after heel contact where ankle sprains are most likely to occur. RESULTS: Subjects increased ankle eversion before and after heel contact during the adaptation period. This increase carried over to the post adaptation period following removal of the weight. The weight also induced an increase in the TA activity before heel contact during late adaptation, although this increase did not carry over to the post adaptation period. No significant changes were observed in ankle dorsiflexion, PL activity, and muscle co-activation. CONCLUSION: Our error-driven approach is feasible to reduce ankle inversion around heel contact in walking, and may have clinical implication on intervention of recurrent ankle sprains.

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.

GaitNet+ARL: A Deep Learning Algorithm for Interpretable Gait Analysis of Chronic Ankle Instability.

Chronic ankle instability (CAI) is a major public health concern and adversely affects people's mobility and quality of life. Traditional assessment methods are subjective and qualitative by means of clinician observation and patient self-reporting, which may lead to inaccurate assessment and reduce the effectiveness of treatment in clinical practice. Gait analysis becomes a commonly used approach for monitoring human motion behaviors, which can be applied to specific diagnosis and assessment of CAI. However, it is still challenging to recognize the pathological gait pattern for CAI subjects. In this paper, we propose an integrated deep learning framework to solve the CAI recognition problem using kinematic data. Specifically, inspired by the biomechanics of human body system, we create a simple graph neural network (GNN), termed GaitNet, that operates on a spatial domain and exploits interactions among 3-D joint coordinates. We also develop an attention reinforcement learning (ARL) model that determines attention weights of frames on a temporal domain, which is combined with GaitNet for prediction. The effectiveness of our method is validated on the kinematic NEU-CAI dataset which is collected in our institution using a stereophotogrammetric system. According to extensive experiments, we demonstrate that the selected key phases (i.e., sequences of frames with high attentions) significantly increase the predictability of the proposed biomechanics-based GNN model to differentiate between CAI cohort and control cohort. Moreover, we show a significant prediction accuracy improvement (20%-25%) by our approach compared to state-of-the-art machine learning and deep learning methods.

Inter-joint coordination variability is associated with pain severity and joint loading in persons with knee osteoarthritis.

As the lower extremity is a linked-joint system, the contribution of movements at the hip and ankle, in addition to the knee, to gait patterns should be considered for persons with knee osteoarthritis (OA). However, the relationships of joint coordination variability to OA symptoms, particularly knee pain, and joint loading is unknown. The purpose of this study was to determine the relationship of joint coordination variability to knee pain severity and joint loading in persons with knee OA. Thirty-four participants with knee OA underwent gait analysis. Vector coding was used to assess coordination variability during the early, mid, and late stance phase. Hip-knee coupling angle variability (CAV) during midstance was associated with Knee Injury and Osteoarthritis Outcome Score (KOOS) pain (r = -0.50, p = 0.002) and Visual Analog Scale pain (r = 0.36, p = 0.04). Knee-ankle CAV during midstance was associated with KOOS pain (r = -0.34, p = 0.05). Hip-knee CAV during early and midstance were associated with knee flexion moment (KFM) impulses (r = -0.46, p = 0.01). Knee-ankle CAV during early and midstance were associated with peak KFM (r = -0.51, p < 0.01; r = -0.70, p < 0.01). Moreover, knee-ankle CAV during early, mid, and late stance phase were associated with KFM impulses (r = -0.53, p < 0.01; r = -0.70, p < 0.01; r = -0.54, p < 0.01). These findings suggest that joint coordination variability may be a factor that influences pain and knee joint loading in persons with knee OA. Statement of Clinical Significance: Movement coordination of the hip, knee, and ankle should be considered in the clinical management and future research related to knee OA.

Locomotor adaptation to resistance during treadmill training transfers to overground walking in human SCI.

Treadmill training has been used as a promising technique to improve overground walking in patients with spinal cord injury (SCI). Previous findings showed that a gait pattern may adapt to a force perturbation during treadmill training and show aftereffects following removal of the force perturbation. We hypothesized that aftereffects would transfer to overground walking to a greater extent when the force perturbation was resisting rather than assisting leg swing during treadmill training. Ten subjects with incomplete SCI were recruited into this study for two treadmill training sessions: one using swing resistance and the other using swing assistance during treadmill stepping. A controlled resistance/assistance was provided to the subjects' right knee using a customized cable-driven robot. The subjects' spatial and temporal parameters were recorded during the training. The same parameters during overground walking were also recorded before and after the training session using an instrumented walkway. Results indicated that stride length during treadmill stepping increased following the release of resistance load and the aftereffect transferred to overground walking. In contrast, stride length during treadmill stepping decreased following the release of assistance load, but the aftereffect did not transfer to overground walking. Providing swing resistance during treadmill training could enhance the active involvement of the subjects in the gait motor task, thereby aiding in the transfer to overground walking. Such a paradigm may be useful as an adjunct approach to improve the locomotor function in patients with incomplete SCI.

Robotic resistance treadmill training improves locomotor function in human spinal cord injury: a pilot study.

OBJECTIVE: To determine whether cable-driven robotic resistance treadmill training can improve locomotor function in humans with incomplete spinal cord injury (SCI). DESIGN: Repeated assessment of the same patients with crossover design. SETTING: Research units of rehabilitation hospitals in Chicago. PARTICIPANTS: Patients with chronic incomplete SCI (N=10) were recruited to participate in this study. INTERVENTIONS: Subjects were randomly assigned to 1 of 2 groups. One group received 4 weeks of assistance training followed by 4 weeks of resistance training, while the other group received 4 weeks of resistance training followed by 4 weeks of assistance training. Locomotor training was provided by using a cable-driven robotic locomotor training system, which is highly backdrivable and compliant, allowing patients the freedom to voluntarily move their legs in a natural gait pattern during body weight supported treadmill training (BWSTT), while providing controlled assistance/resistance forces to the leg during the swing phase of gait. MAIN OUTCOME MEASURES: Primary outcome measures were evaluated for each participant before training and after 4 and 8 weeks of training. Primary measures were self-selected and fast overground walking velocity and 6-minute walking distance. Secondary measures included clinical assessments of balance, muscle tone, and strength. RESULTS: A significant improvement in walking speed and balance in humans with SCI was observed after robotic treadmill training using the cable-driven robotic locomotor trainer. There was no significant difference in walking functional gains after resistance versus assistance training, although resistance training was more effective for higher functioning patients. CONCLUSIONS: Cable-driven robotic resistance training may be used as an adjunct to BWSTT for improving overground walking function in humans with incomplete SCI, particularly for those patients with relatively high function.

Association Rule Mining to Examine Predictors for the Outcome of Gait Rehabilitation Programs in Stroke Survivors.

ABSTRACT: This study presents a novel application of association rule data mining to determine the predictors of the response to locomotor training and home exercise for improving gait after stroke. The study was a secondary data analysis on the Locomotor Experience Applied Post Stroke Trial dataset. The association rule analysis was applied to analyze three interventions: (1) early locomotor training, (2) late locomotor training, and (3) home exercise program. The outcome variable was whether participants poststroke had greater than median improvement in the self-selected comfortable gait speed. Three types of predictors were investigated: (1) demographics, (2) behavioral and medical history, and (3) clinical assessments at baseline. Association rules were generated when they meet two criteria determined based on the data: 10% of support and 70% of confidence. The identified rules showed that the predictors of the response were different across the three interventions, which was inconsistent with the previous report based on traditional logistic regression. However, the rules were identified with high confidence but low support, indicating that they were reliable but did not appear often in the Locomotor Experience Applied Post Stroke Trial dataset. Further investigation of these rules with a larger sample size is warranted before applying them to clinical settings.

Recurrence Quantification Analysis of Ankle Kinematics During Gait in Individuals With Chronic Ankle Instability.

Purpose: An investigation of the ankle dynamics in a motor task may generate insights into the etiology of chronic ankle instability (CAI). This study presents a novel application of recurrence quantification analysis (RQA) to examine the ankle dynamics during walking. We hypothesized that CAI is associated with changes in the ankle dynamics as assessed by measures of determinism and laminarity using RQA. Methods: We recorded and analyzed the ankle position trajectories in the frontal and sagittal planes from 12 participants with CAI and 12 healthy controls during treadmill walking. We used time-delay embedding to reconstruct the position trajectories to a phase space that represents the states of the ankle dynamics. Based on the phase space trajectory, a recurrence plot was constructed and two RQA variables, the percent determinism (%DET) and the percent laminarity (%LAM), were derived from the recurrence plot to quantify the ankle dynamics. Results: In the frontal plane, the %LAM in the CAI group was significantly lower than that in the control group (p < 0.05. effect size = 0.86). This indicated that the ankle dynamics in individuals with CAI is less likely to remain in the same state. No significant results were found in the %DET or in the sagittal plane. Conclusion: A lower frontal-plane %LAM may reflect more frequent switching between different patterns of neuromuscular control states due to the instabilities associated with CAI. With further study and development, %LAM may have the potential to become a useful biomarker for CAI.

Use of thrust joint manipulation by student physical therapists in the United States during clinical education experiences.

Introduction: Thrust joint manipulation (TJM) is used in physical therapy practice and taught in entry-level curricula in the United States (US); however, research regarding implementation by student physical therapists (SPT)s is scarce. Objectives: To explore the use of TJM in SPT clinical education and factors influencing implementation. Methods: In a cross-sectional exploratory study, accredited physical therapy (PT) programs in the US (n = 227) were invited to participate in an electronic survey. SPTs were queried about TJM use and their clinical instructor's (CI) credentials during their final musculoskeletal clinical experience. Results: Forty-five programs participated in the study, consisting of 2,147 SPTs. Of those, 414 (19.3%) responses were used for analysis and 69% reported using TJM. SPTs who utilized TJM were more likely to have a CI who used TJM (p < 0.001) and/or had advanced certification/training in manual therapy (p < .001). A majority of students agreed or strongly agreed that their academic preparation provided them with clinical reasoning tools (84%) and psychomotor skills (69%) necessary to perform TJM. SPT use of TJM was facilitated by CI clinical practice, SPT competence in psychomotor skill, confidence in clinical reasoning, and practice setting. A main barrier to student use of TJM was CI lack of TJM use. Conclusions: Clinical practice of the CI appears to be a key factor in determining student use of TJM. Level of evidence: 2b.

Global rating of change: perspectives of patients with lumbar impairments and of their physical therapists.

Background: Global rating of change (GROC) scores provide a means of measuring patients' self-perceived change in health status over time. Objectives: The purposes of the study were to examine agreement of GROC ratings between the patient (GROCp) and the treating therapist (GROCt), the impact on the minimal clinically important difference (MCID) estimates by reporting resources, and the relationships between the subjective GROC scores and objective outcome measures. Methods: Data from 52,767 patients with orthopedic lumbar spine impairments treated in 623 outpatient rehabilitation clinics in 34 states (United States) were analyzed. Patient's functional status (FS) before and after the treatment was measured using the Lumbar Computerized Adaptive Testing (LCAT) survey (0-100 scale). The GROC ratings were obtained from both the patients and their caring therapists at discharge. Results: On average, GROCp (mean [(SD] = 3.1 [4.1]) was 1.9 points lower than GROCt (mean [SD] = 5.0 [1.9]). There were negligible differences between MCID estimates derived from the patients' GROC ratings (MCID cutoff = 9.2) and from the therapists' GROC ratings (MCID cutoff = 9.5). While only analyzing patient data whose GROCp ≥ 0, the intraclass correlation coefficient between GROCp and GROCt was 0.61, the GROCp correlated with FS at intake at r = 0.12, with FS at discharge at r = 0.56, and with FS change scores at r = 0.47. Conclusions: Therapists tended to report higher GROC ratings than their patients did but there were negligible differences between MCID estimates derived from GROCp and that derived from GROCt.

An examination of muscle force control in individuals with a functionally unstable ankle.

Previous studies suggest that functional ankle instability (FAI) may be associated with deficits in the ability to sense muscle forces. We tested individuals with FAI to determine if they have reduced ability to control ankle muscle forces, which is a function of force sense. Our test was performed isometrically to minimize the involvement of joint position sense and kinesthesia. A FAI group and a control group were recruited to perform an ankle force control task using a platform-based ankle robot. They were asked to move a cursor to hit 24 targets as accurately and as fast as possible in a virtual maze. The cursor movement was based on the direction and magnitude of the forces applied to the robot. Participants underwent three conditions: pre-test (baseline), practice (skill acquisition), and post-test (post skill acquisition). The force control ability was quantified based on the accuracy performance during the task. The accuracy performance was negatively associated with the collision count of the cursor with the maze wall. The FAI group showed reduced ability to control ankle muscle forces compared to the control group in the pre-test condition, but the difference became non-significant in the post-test condition after practice. The change in performance before and after practice may be due to different degrees of reliance on force sense.

Effects of kinesiotaping and athletic taping on ankle kinematics during walking in individuals with chronic ankle instability: A pilot study.

BACKGROUND: Individuals with chronic ankle instability (CAI) tend to walk with an overly inverted foot, which increases the risk of ankle sprains during stance phase. Clinicians could perform ankle taping using kinesiotape (KT) or athletic tape (AT) to address this issue. Because KT is elastic while AT is not, the techniques and underlying mechanisms for applying these tapes are different, which may lead to different outcomes. RESEARCH QUESTION: To compare the effects of KT and AT interventions on foot motion in the frontal plane and tibial motion in the transverse plane during stance phase of walking. METHODS: Twenty subjects with CAI were assigned to either KT or AT group, and walked on a treadmill in no tape and taped conditions. Their foot and tibial motions were captured by 3D motion analysis system. The main component of KT application was two pieces of tape applied from the medial aspect of the hindfoot to the lateral to generate a pulling tension towards eversion. AT was applied to the ankle using the closed basket weave approach. AT was not stretchable and not able to generate the same pulling tension as KT. RESULTS: KT increased foot eversion during early stance, but showed no effect during late stance. AT increased tibial internal rotation during late stance, but showed no effect during early stance. SIGNIFICANCE: Compared to AT, KT better provides a flexible pulling force that facilitates foot eversion during early stance, while not restricting normal inversion in late stance during walking. KT may be a useful clinical tool in correcting aberrant motion while not limiting natural movement in sports.

Rasch Analysis of the Activities-Specific Balance Confidence Scale in Older Adults Seeking Outpatient Rehabilitation Services.

Background The Activities-specific Balance Confidence (ABC) scale measures confidence in performing various ambulatory activities without falling or experiencing a sense of unsteadiness. Objectives This study (1) examined the ABC scale (0-100) using Rasch analysis, (2) assessed statistically reliable change, and (3) developed a functional staging to guide clinical interpretation of a patient's improvement. Methods The authors examined rating-scale structure, item difficulty hierarchy, item fit, person-item match, separation index, differential item functioning, test precision, and unidimensionality. Additionally, this cross-sectional study of 5012 older patients seeking outpatient rehabilitation therapy in 123 clinics estimated the minimal detectable change and developed a functional staging. Results The item "walk outside on icy sidewalks" was the most difficult item, while the item "reach for a small can off a shelf at eye level" was the easiest item. Overall, average patient ability estimates of 56.2 ± 20.3 were slightly higher than the average item difficulty estimates of 45.9 ± 7.8. With a separation index equal to 3.65, the ABC scale items can differentiate individuals into 5.2 statistically distinct strata. Most ABC scale items were free of differential item functioning. For example, "walk outside on icy sidewalks" was easier for patients who were underweight. Results supported unidimensionality of the ABC scale, with the first factor explaining 77% of the total variance. The estimated minimal detectable change was 15 points. The authors provided an example of functional staging application. Conclusion Results supported sound psychometric properties and clinical usage of the ABC scale for older adults seeking outpatient rehabilitation therapy. J Orthop Sports Phys Ther 2018;48(7):574-583. Epub 30 Mar 2018. doi:10.2519/jospt.2018.8023.