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Progress in locomotor rehabilitation has created an increasing need to understand the factors that contribute to motor behavior, to determine whether these factors are modifiable, and if so, to determine how best to modify them in a way that promotes improved function. Currently available clinical measures do not have the capacity to distinguish between neuromotor recovery and compensation for impaired underlying body structure/functions. This Special Interest article examines the state of outcomes measurement in physical therapy in regard to locomotor rehabilitation, and suggests approaches that may improve assessment of recovery and clinical decision-making capabilities. We examine historical approaches to measurement of locomotor rehabilitation outcomes, including rating scales, timed movement tasks, and laboratory-based outcome measures, and we discuss the emerging use of portable technology to assess walking in a free-living environment. The ability to accurately measure outcomes of rehabilitation, both in and away from the clinical/laboratory setting, allows assessment of skill acquisition, retention, and long-term carryover in a variety of environments. Accurate measurement allows behavioral changes to be observed, and assessments to be made, regarding an individual's ability to adapt during interventions and to incorporate new skills into real-world behaviors. The result of such an approach to assessment may be that interventions truly translate from clinical/laboratory to real-world environments. Future locomotor measurement tools must be based on a theoretical framework that can guide their use to accurately quantify treatment effects and provide a basis upon which to develop and refine therapeutic interventions.

Background : In this pilot study, we examined the effects of ipsilesional high-frequency rTMS (iHF-rTMS) and contralesional low-frequency rTMS (cLF-rTMS) applied via a double-cone coil on neurophysiological and gait variables in patients with chronic stroke. Objective/Hypothesis : To determine the group and individual level effects of two types of stimulation to better individualize neuromodulation for rehabilitation. Methods : Using a randomized, within-subject, double-blind, sham-controlled trial with 14 chronic stroke participants iHF-rTMS and cLF-rTMS were applied via a double-cone coil to the tibialis anterior cortical representation. Neurophysiological and gait variables were compared pre-post rTMS. Results : A small effect of cLF-rTMS indicated increased MEP amplitudes (Cohen's D; cLF-rTMS, d = −0.30). Group-level analysis via RMANOVA showed no significant group effects of stimulation (P > 0.099). However, secondary analyses of individual data showed a high degree of response variability to rTMS. Individual percent changes in resting motor threshold and normalized MEP latency correlated with changes in gait propulsive forces and walking speed (iHF-rTMS, nLAT:Pp, R = 0.632 P = 0.015; cLF-rTMS, rMT:SSWS, R = −0.557, P = 0.039; rMT:Pp, R = 0.718, P = 0.004). Conclusions : Changes in propulsive forces and walking speed were seen in some individuals that showed neurophysiological changes in response to rTMS. The neurological consequences of stroke are heterogeneous making a "one type fits all" approach to neuromodulation for rehabilitation unlikely. This pilot study suggests that an individual's unique response to rTMS should be considered before the application/selection of neuromodulatory therapies. Before neuromodulatory therapies can be incorporated into standard clinical practice, additional work is needed to identify biomarkers of response and how best to prescribe neuromodulation for rehabilitation for post-stroke gait. [ABSTRACT FROM AUTHOR]

Background: In walking rehabilitation trials, self-selected walking speed (SSWS) has emerged as the dominant outcome measure to assess walking ability. However, this measure cannot differentiate between recovery of impaired movement and compensation strategies. Spatiotemporal variables and asymmetry ratios are frequently used to quantify gait deviations and are hypothesized markers of recovery. Objectives: The purpose of this review is to investigate spatiotemporal variables and asymmetry ratios as mechanistic recovery measures in physical therapy intervention studies post-stroke. Methods: A systematic literature search was performed to identify physical therapy intervention studies with a statistically significant change in SSWS post intervention and concurrently collected spatiotemporal variables. Methodological quality was assessed using the Cochrane Collaboration's tool. Walking speed, spatiotemporal, and intervention data were extracted. Results: 46 studies met the inclusion criteria, 41 of which reported raw spatiotemporal measures and 19 reported asymmetry ratio calculations. Study interventions included: aerobic training (n = 2), functional electrical stimulation (n = 5), hippotherapy (n = 2), motor dual task training (n = 2), multidimensional rehabilitation (n = 4), robotics (n = 4), sensory stimulation training (n = 8), strength/resistance training (n = 4), task specific locomotor rehabilitation (n = 9), and visually guided training (n = 6). Conclusions: Spatiotemporal variables help describe gait deviations, but scale to speed, so consequently, may not be an independent factor in describing functional recovery and gains. Therefore, these variables are limited in explaining mechanistic changes involved in improving gait speed. Use of asymmetry measures provides additional information regarding the coordinative requirements for gait and can potentially indicate recovery. Additional laboratory-based mechanistic measures may be required to truly understand how walking speed improves. [ABSTRACT FROM AUTHOR]

Background:Regaining locomotor ability is a primary goal in stroke rehabilitation and is most commonly measured using changes in self-selected walking speed. However, walking speed cannot identify the mechanisms by which an individual recovers. Laboratory-based mechanistic measures such as exercise capacity, muscle activation, force production, and movement analysis variables may better explain neurologic recovery. Objectives:The objectives of this systematic review are to examine changes in mechanistic gait outcomes and describe motor recovery as quantified by changes in laboratory-based mechanistic variables in rehabilitation trials. Methods:Following a systematic literature search (in PubMed, Ovid, and CINAHL), we included rehabilitation trials with a statistically significant change in self-selected walking speed post-intervention that concurrently collected mechanistic variables. Methodological quality was assessed using Cochrane Collaboration’s tool. Walking speed changes, mechanistic variables, and intervention data were extracted. Results:Twenty-five studies met the inclusion criteria and examined: cardiorespiratory function (n = 5), muscle activation (n = 5), force production (n = 11), and movement analysis (n = 10). Interventions included: aerobic training, functional electrical stimulation, multidimensional rehabilitation, robotics, sensory stimulation training, strength/resistance training, task-specific locomotor rehabilitation, and visually-guided training. Conclusions:Following this review, no set of outcome measures to mechanistically explain changes observed in walking speed were identified. Nor is there a theoretical basis to drive the complicated selection of outcome measures, as many of these outcomes are not independent of walking speed. Since rehabilitation literature is yet to support a causal, mechanistic link for functional gains post-stroke, a systematic, multimodal approach to stroke rehabilitation will be necessary in doing so. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To identify the clinical measures associated with improved walking speed after locomotor rehabilitation in individuals poststroke and how those who respond with clinically meaningful changes in walking speed differ from those with smaller speed increases. Design: A single group pre-post intervention study. Participants were stratified on the basis of a walking speed change of greater than (responders) or less than (nonresponders) .16m/s. Paired sample t tests were run to assess changes in each group, and correlations were run between the change in each variable and change in walking speed. Setting: Outpatient interdisciplinary rehabilitation research center. Participants: Hemiparetic subjects (N=27) (17 left hemiparesis; 19 men; age: 58.74±12.97y; 22.70±16.38mo poststroke). Intervention: A 12-week locomotor intervention incorporating training on a treadmill with body weight support and manual trainers accompanied by training overground walking. Main Outcome Measures: Measures of motor control, balance, functional walking ability, and endurance were collected at pre- and postintervention assessments. Results: Eighteen responders and 9 nonresponders differed by age (responders=63.6y, nonresponders=49.0y, P=.001) and the lower extremity Fugl-Meyer Assessment score (responders=24.7, nonresponders=19.9, P=.003). Responders demonstrated an average improvement of .27m/s in walking speed as well as significant gains in all variables except daily step activity and paretic step ratio. Conversely, nonresponders demonstrated statistically significant improvements only in walking speed and endurance. However, the walking speed increase of .10m/s was not clinically meaningful. Change in walking speed was negatively correlated with changes in motor control in the nonresponder group, implying that walking speed gains may have been accomplished via compensatory mechanisms. Conclusions: This study is a step toward discerning the underlying factors contributing to improved walking performance. [Copyright &y& Elsevier]

Recovery of walking after incomplete spinal cord injury (iSCI) is a common focus of rehabilitation, but few measurement tools capture walking performance outside the clinic or laboratory. This study determined the accuracy and test-retest reliability of the Step Activity Monitor (SAM), a microprocessor- driven accelerometer that measures walking activity. We evaluated 11 individuals with iSCI during replicate 6-minute walk tests (maws) and 10-meter walk tests (10mWTs) scheduled <1 week apart. The SAM was 97% accurate compared with hand-tallied step counts. SAM values were stable across repeated walking performances (intraclass correlation coefficient = 0.97-0.99). Standard error of measurement values were 6.0 steps and 0.8 steps for the 6MWT and 10mWT, respectively. Ninety-five percent confidence intervals were 203.7 to 177.0 steps for the 6MWT and 16.1 to 12.7 steps for the 10mWT. The SAM is an accurate and reliable device for capturing walking activity in individuals with iSCI. [ABSTRACT FROM AUTHOR]

Abstract: Balasubramanian CK, Bowden MG, Neptune RR, Kautz SA. Relationship between step length asymmetry and walking performance in subjects with chronic hemiparesis. Objective: To understand the relationship between step length asymmetry and hemiparetic walking performance. Design: Descriptive. Setting: Gait analysis laboratory. Participants: Convenience sample of 49 subjects with chronic hemiparesis. Interventions: Not applicable. Main Outcome Measures: Subjects walked at their self-selected walking speed over both an instrumented mat and forceplates to collect spatiotemporal parameters and ground reaction forces, respectively. Step length asymmetry was quantified by using a step length ratio (SLR) defined as paretic step length divided by nonparetic step length. Paretic leg propulsion, self-selected walking speed, hemiparetic severity (assessed by Brunnstrom stages of motor recovery), and some spatiotemporal walking parameters quantified the hemiparetic walking performance. Paretic leg propulsion was quantified by the paretic propulsion (PP) ratio, calculated as the percentage contribution of paretic leg to the total propulsive impulse. Results: Significant negative correlation (r=−.78) was revealed between SLR and PP, indicating that subjects generating less propulsive force with the paretic leg walked asymmetrically with longer paretic steps than nonparetic steps. SLR and self-selected walking speed revealed a weaker correlation (r=−.35), whereas hemiparetic severity correlated strongly with SLR (ρ=−.53). Conclusions: Step length asymmetry is related to propulsive force generation during hemiparetic walking. Subjects generating least paretic propulsion walk with relatively longer paretic steps. This suggests that one of the mechanisms for the longer paretic step may be the relatively greater compensatory nonparetic leg propulsion. Further, those with more severe hemiparesis (those dependent on abnormal flexor and extensor synergies) walk with the longest paretic steps relative to nonparetic. Finally, our results indicated that asymmetrical step lengths may not necessarily limit the self-selected walking speed, likely due to other compensatory mechanisms. [Copyright &y& Elsevier]

Slow walking speed and lack of balance control are common impairments post-stroke. While locomotor training often improves walking speed, its influence on dynamic balance is unclear. The goal of this study was to assess the influence of a locomotor training program on dynamic balance in individuals post-stroke during steady-state walking and determine if improvements in walking speed are associated with improved balance control. Kinematic and kinetic data were collected pre- and post-training from seventeen participants who completed a 12-week locomotor training program. Dynamic balance was quantified biomechanically (peak-to-peak range of frontal plane whole-body angular-momentum) and clinically (Berg-Balance-Scale and Dynamic-Gait-Index). To understand the underlying biomechanical mechanisms associated with changes in angular-momentum, foot placement and ground-reaction-forces were quantified. As a group, biomechanical assessments of dynamic balance did not reveal any improvements after locomotor training. However, improved dynamic balance post-training, observed in a sub-group of 10 participants (i.e., Responders), was associated with a narrowed paretic foot placement and higher paretic leg vertical ground-reaction-force impulse during late stance. Dynamic balance was not improved post-training in the remaining seven participants (i.e., Non-responders), who did not alter their foot placement and had an increased reliance on their nonparetic leg during weight-bearing. As a group, increased walking speed was not correlated with improved dynamic balance. However, a higher pre-training walking speed was associated with higher gains in dynamic balance post-training. These findings highlight the importance of the paretic leg weight bearing and mediolateral foot placement in improving frontal plane dynamic balance post-stroke. [ABSTRACT FROM AUTHOR]

Objective To investigate the dimensionality and item-difficulty hierarchy of the Fugl-Meyer Assessment of the lower extremity (FMA-LE). Design Secondary analyses of data pooled from 4 existing datasets: a phase III randomized controlled trial investigating the effectiveness of body weight support and a treadmill for rehabilitation of walking poststroke, and 3 cross-sectional studies investigating the link between impaired motor performance poststroke and walking. Setting University research centers and rehabilitation centers. Participants A pooled sample of individuals with a stroke (N=535, men=313; mean age ± SD, 61.91±12.42y). Interventions Not applicable. Main Outcome Measures Confirmatory factor analyses (CFA) and Rasch residual principal component analysis (PCA) investigated the dimensionality of the FMA-LE. The Rasch analysis rating scale model investigated item-difficulty hierarchy of the FMA-LE. Results The CFA showed adequate fit of a 3-factor model, with 2 out of 3 indices (CFA=.95; Tucker-Lewis Index=.94; root mean square error of approximation=.124) showing good model fit. Rasch PCA showed that removal of the reflex and coordination items explained 90.8% of variance in the data, suggesting that the abnormal synergy items contributed to the measurement of a unidimensional construct. However, rating scale model results revealed deviations in the item-difficulty hierarchy of the unidimensional abnormal synergy items from the originally proposed stepwise sequence of motor recovery. Conclusions Our findings suggest that the FMA-LE might represent a multidimensional construct, challenging the use of a total score of the FMA-LE to predict lower extremity motor recovery. Removal of the misfit items resulted in creation of a unidimensional scale composed of the abnormal synergy items. However, this unidimensional scale deviates from the originally proposed hierarchical ordering. [ABSTRACT FROM AUTHOR]

Abstract Stroke is the leading cause of long-term disability and individuals post-stroke often experience impaired walking ability. The plantarflexor (PF) muscles are critical to walking through their contributions to the ground reaction forces and body segment energetics. Previous studies have shown muscle activity during walking can be grouped into co-excited muscle sets, or modules. Improper co-activation, or merging of modules, is a common impairment in individuals post-stroke. The purpose of this study was to determine the influence of merged PF modules on walking performance in individuals post stroke by examining balance control , body support and propulsion, and walking symmetry. Muscle modules were identified using non-negative matrix factorization to classify subjects as having an independent or merged PF module. The merged group had decreased balance control with a significantly higher frontal plane whole-body angular momentum than both the independent and control groups, while the independent and control groups were not significantly different. The merged group also had higher paretic braking and nonparetic propulsion than both the independent and control groups. These results remained when comparisons were limited to subjects who had the same number of modules, indicating this was not a general effect due to subjects with merged PF having fewer modules. It is likely that a merged PF module is indicative of general PF dysfunction even when some activation occurs at the appropriate time. These results suggest an independent PF module is critical to walking performance, and thus obtaining an independent PF module should be a crucial aim of stroke rehabilitation. [ABSTRACT FROM AUTHOR]

Kinematic and kinetic outcome measures are tightly linked in walking. Although altering motor output is a major goal of gait rehabilitation, little is understood regarding the relationship between altering a single kinematic variable and kinetic outcome changes.We designed a strategy to isolate hip extension alterations during walking on a treadmill to assess the change in kinetic outcomes. Ten healthy individuals walked on an instrumented split-belt treadmill with motion capture to calculate hip extension and kinetic outcomes at the following five different randomized cadences: self-selected cadence, self-selected ± 10%, and self-selected ± 20%. The treadmill speed was held constant at the individual's self-selected walking speed, forcing cadence changes to result in successful alterations to hip extension, varying 8.3 degrees from the self-selected -20% to +20% cadence conditions. Kinetic outcomes demonstrated similar alterations. Hip extension changes at each cadence significantly correlated with kinetic changes in propulsive impulse (r = 0.852, P < 0.001), peak ankle power (r = 0.473, P = 0.002), and ankle plantarflexion work (r = 0.762, P < 0.001). These results demonstrate that kinetic outcomes are highly alterable in response to a kinematic gait change. This clinically relevant finding highlights the potential to improve motor output in individuals during rehabilitation by altering gait patterns to achieve more optimal limb positions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Translation of motion analysis data from the lab to clinical practice remains elusive. [•] Portable accelerometers can measure elements of human movement outside of the laboratory. [•] Center of mass acceleration can infer information about force generation during walking. [•] Step activity determined from accelerometers is related to community participation. [•] We need to determine if these data can guide clinical decision making and treatment design. [Copyright &y& Elsevier]

This study examined the experiences of persons with incomplete spinal cord injury who participated in locomotor training (LT). LT is an emerging rehabilitation intervention for enhancing the recovery of walking in persons with central nervous system disorders. Multiple interviews and field observations provided data from eight participants, including four veterans. Findings indicate that experiences of bodily changes were prevalent among participants. Themes included (1) experiencing impaired or absent proprioception, (2) struggling for bodily control, and (3) experiencing emergent bodily sensations. Themes 1 and 2 reflected bodily disruption as a result of spinal cord injury and were challenging to participants as they attempted to reconnect the body and self through LT. Theme 3 reflected bodily sensations (burning, soreness) that were seen as positive signs of recovery and resulted in hope and motivation. Understanding how LT participants experience bodily changes may enable therapists to develop improved participant- centered intervention approaches. [ABSTRACT FROM AUTHOR]