Autonomous Control of Music to Retrain Walking After Stroke.

BACKGROUND: Post-stroke care guidelines highlight continued rehabilitation as essential; however, many stroke survivors cannot participate in outpatient rehabilitation. Technological advances in wearable sensing, treatment algorithms, and care delivery interfaces have created new opportunities for high-efficacy rehabilitation interventions to be delivered autonomously in any setting (ie, clinic, community, or home). METHODS: We developed an autonomous rehabilitation system that combines the closed-loop control of music with real-time gait analysis to fully automate patient-tailored walking rehabilitation. Specifically, the mechanism-of-action of auditory-motor entrainment is applied to induce targeted changes in the post-stroke gait pattern by way of targeted changes in music. Using speed-controlled biomechanical and physiological assessments, we evaluate in 10 individuals with chronic post-stroke hemiparesis the effects of a fully-automated gait training session on gait asymmetry and the energetic cost of walking. RESULTS: Post-treatment reductions in step time (Δ: -12 ± 26%, P = .027), stance time (Δ: -22 ± 10%, P = .004), and swing time (Δ: -15 ± 10%, P = .006) asymmetries were observed together with a 9 ± 5% reduction (P = .027) in the energetic cost of walking. Changes in the energetic cost of walking were highly dependent on the degree of baseline energetic impairment (r =- .90, P < .001). Among the 7 individuals with a baseline energetic cost of walking larger than the normative value of healthy older adults, a 13 ± 4% reduction was observed after training. CONCLUSIONS: The closed-loop control of music can fully automate walking rehabilitation that markedly improves walking after stroke. Autonomous rehabilitation delivery systems that can safely provide high-efficacy rehabilitation in any setting have the potential to alleviate access-related care gaps and improve long-term outcomes after stroke.

Health Promotion and Wellness in Neurologic Physical Therapy: Strategies to Advance Practice.

BACKGROUND AND PURPOSE: Neurologic physical therapy (PT) can assist people with neurologic conditions and injuries to optimize their health and well-being by addressing barriers at the individual, relationship, community, and societal levels. The purpose of this special interest article is to provide consensus-driven strategies to address barriers to implementing health promotion and wellness (HPW)-related neurologic PT practice. SUMMARY OF KEY POINTS: Environmental scan, literature review, and expert input were used to determine barriers and develop strategies. Barriers include lack of time; low knowledge, self-efficacy, and awareness; client complexity; and lack of HPW resources; as well as concerns regarding payment and scope of practice. Four key strategies emerged: (1) develop and disseminate a consensus-based scope of practice for HPW in neurologic PT; (2) increase knowledge of resources related to HPW; (3) promote delivery models for HPW-related neurologic PT; and (4) encourage advocacy, community building and partnership along the continuum of care. RECOMMENDATIONS FOR CLINICAL PRACTICE: Clinicians should practice to their full scope of HPW-related PT practice. This includes optimizing movement, including physical activity and fitness, as well as reinforcing the importance of healthy sleep, nutrition, stress, and smoking cessation. These activities address primary, secondary, and tertiary prevention. Clinicians are encouraged to report their experiences with HPW-focused delivery models and outcomes. Additional research is needed to understand the full impact of HPW on PT practice (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A364).

The ABLE scale: the development and psychometric properties of an outcome measure for the spinal cord injury population.

BACKGROUND: A paucity of information exists on the psychometric properties of several balance outcome measures. With the exception of the Modified Functional Reach Test, none of these balance outcome measures were developed specifically for the population with spinal cord injury (SCI). A new balance assessment tool for people with SCI, the Activity-based Balance Level Evaluation (ABLE scale), was developed and tested. OBJECTIVE: The purposes of this study were: (1) to develop a scale capturing the wide spectrum of functional ability following SCI and (2) to assess the initial psychometric properties of the scale using a Rasch analysis. DESIGN: A methodological research design was used to test the initial psychometric properties of the ABLE scale. METHODS: The Delphi technique was used to establish the original 28-item ABLE scale. People with SCI at each of 4 centers (n=104) were evaluated using the ABLE scale. A Rasch analysis was conducted to test for targeting, item difficulty, item bias, and unidimensionality. An analysis of variance was completed to test for discriminant validity. RESULTS: The Rasch analysis revealed a scale with minimal floor and ceiling effects and a wide range of item difficulty capturing the large scope of functional capacity after SCI. Multiple redundancies of item difficulty were observed. Limitations All raters were experienced physical therapists, which may have skewed the results. The sample size of 104 participants precluded a principal component analysis. CONCLUSION: Development of an all-inclusive clinical instrument assessing balance in the SCI population was accomplished using the Delphi technique. Modifications of the ABLE scale based on the Rasch analysis yielded a 28-item scale with minimal floor or ceiling effects. Larger studies using the revised scale and factor analyses are necessary to establish unidimensionality and reduction of the total item number.

Validity of acute and chronic tactile sensory testing after spinal cord injury in rats.

Spinal cord injury (SCI) impairs sensory systems causing allodynia. Measuring the development of allodynia in rodent models of SCI is challenging due to spinal shock and marked motor impairments. Assessment of SCI-induced allodynia is not standardized across labs, making interpretation of results difficult. Therefore, we validated sensory threshold assessment after SCI and developed a novel assessment of allodynia prior to motor recovery in a rat SCI model. One hundred fifty-six Sprague-Dawley rats received T8 laminectomy or mild to moderate SCI using the OSU SCI device (0.3 mm to 1.3 mm cord displacement). To determine tactile thresholds, von Frey hairs (VFH) were applied in Up-Down or ascending order to the dorsal or plantar hindpaw. The most efficient and valid procedures that maintain high sensitivity and specificity were identified. Ten Up-Down VFH applications yielded stable thresholds; reducing the risk of threshold decay and unnecessary exposure to painful stimuli. Importantly, distraction of SCI-rats with food revealed differential decay of thresholds than when distraction is not provided. The new test uses dorsal VFH stimulation and is independent of trunk or hindlimb control. Acute dorsal VFH thresholds collected before recovery of hindlimb weight support accurately predicted plantar VFH thresholds measured at late timepoints (chi(2)=8.479; p<0.05). Thus, standardized testing early after SCI using the dorsal VFH test or later using 10 stimuli in the Up-Down test produces valid measures of tactile sensation across many SCI severities. Early detection of allodynia in experimental SCI will allow identification of mechanisms responsible for pain development and determine targets for therapeutic interventions.

Three exercise paradigms differentially improve sensory recovery after spinal cord contusion in rats.

Spinal cord injury (SCI) induces incapacitating neuropathic pain in the form of allodynia-a painful response to normally non-noxious stimuli. Unfortunately, the underlying mechanisms of these sensory changes are not well understood, and effective treatments for allodynia have proven elusive. We examined whether physical exercise can improve sensory function after experimental SCI by promoting neurotrophin expression in the spinal cord and periphery, which modulates synaptic transmission and function. Female rats with moderate spinal cord contusion participated in treadmill training, swim training, stand training or were untrained. Exercise training began 4 days post surgery, lasted 20-25 min per day, 5 days a week for 7 weeks. Allodynia, as measured using von Frey hairs of different bending forces to the plantar hind paw, developed in the untrained group 3 weeks after SCI. Treadmill training ameliorated allodynia and restored normal sensation by 5 weeks. Swim training had a transient beneficial effect, but allodynia returned by 7 weeks. Stand training had no effect. Resolution of allodynia after treadmill training was associated with normal mRNA levels of brain-derived neurotrophic factor (BDNF) in both the lumbar spinal cord and soleus muscle. No other exercise paradigm restored BDNF centrally and peripherally. Greater recovery from allodynia correlated significantly with the degree of normalization of central and peripheral BDNF levels. These findings suggest that rhythmic, weight-bearing exercise may be an effective intervention to counter SCI-induced allodynia.