Michelle Kahn

Strength training for walking in neurologic rehabilitation is not task specific: a focused review

ABSTRACTThe aim of this systematic review was to investigate the task specificity of strength training programs for walking in neurologic rehabilitation. Nine electronic databases were searched from conception to October 2012 for randomized controlled trials that used strength training to improve walking in adult neurologic populations. The search identified 25 randomized controlled trials that investigated the efficacy of strength training to improve walking in people with a variety of neurologic conditions. The results revealed that despite significant strength gains, many studies failed to show a significant improvement in walking capacity. Most studies did not include exercises relating to all three main power events important for walking. Strength testing and strengthening exercises were prioritized for the knee extensors and flexors, despite their relatively minor role in human walking. Strengthening exercises performed in the neurologic population are not specific to the main muscle groups responsible for the power generation required for walking. There is a predisposition for strength testing and strengthening exercises to focus on the knee flexors and extensors despite their relatively minor role during walking. Further consideration of the specificity of strength training may provide greater translation of strength gains to improved walking outcomes.

Clinical tests of ankle plantarflexor strength do not predict ankle power generation during walking.

ObjectiveThe aim of this study was to investigate the relationship between a clinical test of ankle plantarflexor strength and ankle power generation (APG) at push-off during walking. DesignThis is a prospective cross-sectional study of 102 patients with traumatic brain injury. Outcome MeasuresHandheld dynamometry was used to measure ankle plantarflexor strength. Three-dimensional gait analysis was performed to quantify ankle power generation at push-off during walking. ResultsAnkle plantarflexor strength was only moderately correlated with ankle power generation at push-off (r = 0.43, P < 0.001; 95% confidence interval, 0.26–0.58). There was also a moderate correlation between ankle plantarflexor strength and self-selected walking velocity (r = 0.32, P = 0.002; 95% confidence interval, 0.13–0.48). ConclusionsHandheld dynamometry measures of ankle plantarflexor strength are only moderately correlated with ankle power generation during walking. This clinical test of ankle plantarflexor strength is a poor predictor of calf muscle function during gait in people with traumatic brain injury.

Methods of assessing associated reactions of the upper limb in stroke and traumatic brain injury: A systematic review

Abstract Objective: To determine the assessment methods for upper limb (UL) associated reactions (ARs) in people with acquired brain injury (ABI). Methods: A systematic search of 10 databases was performed for Stage 1 to identify methods that quantify ARs of the hemiplegic UL. Stage 2 searched four databases to examine the clinimetric properties and clinical utility of these methods. Two independent reviewers identified relevant articles, extracted data, assessed study methodological quality and rated the clinimetric properties and clinical utility. Results: Eighteen articles were included. The methods used to evaluate ARs were surface electromyography (11), goniometry (5), dynamometry (5), electrogoniometry (1), subjective clinician (2) and patient rating forms (2). Electromyography, electrogoniometry and dynamometry implemented stationary, seated positions using maximal voluntary contractions of the less impaired UL as the provocative task. Standard goniometry most frequently tested ARs dynamically, using a mobility task to provoke the AR. There was limited clinimetric data available. Only half of the assessment methods were deemed clinically feasible. The most common methods were laboratory-based. Conclusion: There were a limited number of methods used to assess ARs in people with ABI and the measurement properties of these outcomes were largely unreported. No gold standard was identified.

Assessment of the internal construct validity of the revised High-Level Mobility Assessment Tool for traumatic orthopaedic injuries

Objective: To determine whether the revised High-Level Mobility Assessment Tool (HiMAT) was valid for measuring mobility for people with multi-trauma orthopaedic lower limb injuries. Design: Cross-sectional study. Subjects: Participants with lower limb multi-trauma orthopaedic injuries. Methods: One complete revised HiMAT was obtained for 106 people within 12 weeks of being allowed to fully weight bear. Rasch analysis was used to assess the overall fit of the model for individuals and items, differential item functioning, local dependency, targeting of items and dimensionality. Results: The mean revised HiMAT score was 10.5 (SD = 6.8) with a range of 5–30. Rasch analysis of revised HiMAT showed adequate overall fit to the model (P = 0.29) with no misfitting items (fit residual SD = 0.69) or persons (fit residual SD = 0.62). The scale showed good internal consistency (Person Separation Index = 0.91). One item (hopping) demonstrated disordered thresholds, however this item had good fit to the model in all other aspects. The revised HiMAT was unidimensional, and no differential item functioning was detected for gender or age. The revised HiMAT was well targeted for this group with a range of items across all ability levels. Conclusion: The results of this study support the internal construct validity of the revised HiMAT as a well-targeted, unidimensional measure of high-level mobility with no ceiling or floor effect for males and females recovering from multi-trauma orthopaedic lower limb injuries.

Lower limb angular velocity during walking at various speeds

BACKGROUND Although it is well established that lower limb joint angles adapt to walking at various speeds, limited research has examined the modifications in joint angular velocity. There is currently no normative dataset for joint angular velocity during walking, which would be useful to allow comparisons for patient cohorts. Additionally, understanding normal joint angular velocity may assist clinical assessment and treatment procedures to incorporate methods that replicate the movement speed of the lower limb joints during walking. RESEARCH QUESTION This study aimed to examine lower limb joint angles and angular velocities in a healthy population walking at various gait speeds. METHODS Thirty-six healthy adult participants underwent three-dimensional gait analysis while walking at various speeds during habitual and slowed walking. The peak joint angles and angular velocities during important phases of the gait cycle were examined for the hip, knee and ankle in the sagittal plane. Data were grouped in 0.2 m/s increments from a walking speed of 0.4 m/s to 1.6 m/s to represent the range of walking speeds reported in studies of people with gait impairments. RESULTS For joint angles and angular velocities, the shape of the gait traces were consistent regardless of the walking speed. However as walking speed increased, so did the peak joint angles and angular velocities for the hip, knee and ankle. The largest angular velocity occurred when the knee joint extended at the terminal swing phase of gait. For the ankle and hip joints, the largest angular velocity occurred during the push-off phase. SIGNIFICANCE This study examined how lower limb joint angular velocities change with various walking speeds. These data can be used as a comparator for data from clinical cohorts, and has the potential to be used to match clinical assessment and treatment methods to joint angular velocity during walking.BACKGROUND Although it is well established that lower limb joint angles adapt to walking at various speeds, limited research has examined the modifications in joint angular velocity. There is currently no normative dataset for joint angular velocity during walking, which would be useful to allow comparisons for patient cohorts. Additionally, understanding normal joint angular velocity may assist clinical assessment and treatment procedures to incorporate methods that replicate the movement speed of the lower limb joints during walking. RESEARCH QUESTION This study aimed to examine lower limb joint angles and angular velocities in a healthy population walking at various gait speeds. METHODS Thirty-six healthy adult participants underwent three-dimensional gait analysis while walking at various speeds during habitual and slowed walking. The peak joint angles and angular velocities during important phases of the gait cycle were examined for the hip, knee and ankle in the sagittal plane. Data were grouped in 0.2 m/s increments from a walking speed of 0.4 m/s to 1.6 m/s to represent the range of walking speeds reported in studies of people with gait impairments. RESULTS For joint angles and angular velocities, the shape of the gait traces were consistent regardless of the walking speed. However as walking speed increased, so did the peak joint angles and angular velocities for the hip, knee and ankle. The largest angular velocity occurred when the knee joint extended at the terminal swing phase of gait. For the ankle and hip joints, the largest angular velocity occurred during the push-off phase. SIGNIFICANCE This study examined how lower limb joint angular velocities change with various walking speeds. These data can be used as a comparator for data from clinical cohorts, and has the potential to be used to match clinical assessment and treatment methods to joint angular velocity during walking.