Impaired limb shortening following stroke: what's in a name?

BackgroundDifficulty advancing the paretic limb during the swing phase of gait is a prominent manifestation of walking dysfunction following stroke. This clinically observable sign, frequently referred to as 'foot drop', ostensibly results from dorsiflexor weakness.ObjectiveHere we investigated the extent to which hip, knee, and ankle motions contribute to impaired paretic limb advancement. We hypothesized that neither: 1) minimal toe clearance and maximal limb shortening during swing nor, 2) the pattern of multiple joint contributions to toe clearance and limb shortening would differ between post-stroke and non-disabled control groups.MethodsWe studied 16 individuals post-stroke during overground walking at self-selected speed and nine non-disabled controls who walked at matched speeds using 3D motion analysis.ResultsNo differences were detected with respect to the ankle dorsiflexion contribution to toe clearance post-stroke. Rather, hip flexion had a greater relative influence, while the knee flexion influence on producing toe clearance was reduced.ConclusionsSimilarity in the ankle dorsiflexion, but differences in the hip and knee, contributions to toe clearance between groups argues strongly against dorsiflexion dysfunction as the fundamental impairment of limb advancement post-stroke. Marked reversal in the roles of hip and knee flexion indicates disruption of inter-joint coordination, which most likely results from impairment of the dynamic contribution to knee flexion by the gastrocnemius muscle in preparation for swing. These findings suggest the need to reconsider the notion of foot drop in persons post-stroke. Redirecting the focus of rehabilitation and restoration of hemiparetic walking dysfunction appropriately, towards contributory neuromechanical impairments, will improve outcomes and reduce disability

The Integration of Principles of Motor Learning to Reduce Gait Asymmetry Using a Novel Robotic Device in Individuals Chronically Post-Stroke

Unilateral deficits resulting from stroke manifest as reduced velocity, decreased cadence and asymmetries in temporal, spatial and force parameters during ambulation. Gait asymmetries and compensatory strategies employed during gait result in a higher mechanical energy cost that limits activity and community participation. Despite conventional rehabilitation efforts, individuals often remain with chronic gait deficits after stroke. Robotic-based therapies have been developed as an alternative to conventional rehabilitation. These therapies offer the means to provide task-specific training at an intensity greater than that of conventional approaches; however, to date outcomes have been similar to that of conventional training. One factor potentially contributing to the limited efficacy of robotic training is the active-assist control strategy that is often employed. This type of training strategy reduces the users’ engagement in the learning process and limits skilled learning. The tethered pelvic assist device (TPAD) is a robotic device that employs actuated tethers at the pelvis to guide the user along a pre-set movement trajectory. While other robotic devices restrict movement to a fixed trajectory, the TPAD promotes shifting weight onto the paretic limb, but permits users to freely move the limb to navigate spatiotemporal aspects of training independently. This allows individuals to participate in the problem-solving process required for motor learning to occur, facilitating a more active role in the motor task itself, and thus promoting learning. Earlier work utilized the TPAD to reduce gait asymmetry in a population of individuals in the chronic phase after stroke in a single training session (Bishop et al., 2015; Vashista, 2015). Results demonstrated an increase in propulsive forces of the affected limb as a result of the intervention, but these gains did not transfer to overground gait. A follow up study explored the feasibility and efficacy of two different training strategies using the TPAD (Bishop et al., 2017). Both training strategies proved feasible and similarly efficacious. The current work examines the feasibility and preliminary efficacy of a five-day intervention using the TPAD with faded visual feedback and a short bout of task-specific overground training to reduce gait asymmetry in a population of individuals at least six months after stroke. Participants underwent a series of three Pre Test assessments within a one-week interval prior to initiating the intervention. Training occurred over five consecutive days, with a Post Test assessment administered on conclusion of Day 5 of training. A one-week Follow Up assessment was also recorded. Results demonstrated this intervention coupling TPAD training with additional tenets of motor learning including visual feedback and salient task-specific overground training was feasible in terms of safety, tolerance and adherence. Further, while participant’s load asymmetry was not significantly reduced on the treadmill from Baseline to Post Training (p >0.05), there was a significant improvement in stance symmetry during overground gait (F = 8.498, p = 0.002). These results suggest that the integration of motor learning tenets with robotic TPAD training was useful in facilitating gains to overground walking. Implications to the broader scope of robotic training suggest that creating an environment in which the user plays a more active role is useful at maximizing effects of robotic training. Future work should include comparison groups (TPAD treadmill training, overground training, and combined TPAD and overground training) with a more robust sample size for a longer duration of training to parse out contributing factors to overground gains. Future work should also consider a longer training and follow up interval in an effort to determine whether individuals are able to maintain improvements longer than the immediate post training period

Permutation entropy and irreversibility in gait kinematic time series from patients with mild cognitive decline and early alzheimer’s dementia

Gait is a basic cognitive purposeful action that has been shown to be altered in late stages of neurodegenerative dementias. Nevertheless, alterations are less clear in mild forms of dementia, and the potential use of gait analysis as a biomarker of initial cognitive decline has hitherto mostly been neglected. Herein, we report the results of a study of gait kinematic time series for two groups of patients (mild cognitive impairment and mild Alzheimer’s disease) and a group of matched control subjects. Two metrics based on permutation patterns are considered, respectively measuring the complexity and irreversibility of the time series. Results indicate that kinematic disorganisation is present in early phases of cognitive impairment; in addition, they depict a rich scenario, in which some joint movements display an increased complexity and irreversibility, while others a marked decrease. Beyond their potential use as biomarkers, complexity and irreversibility metrics can open a new door to the understanding of the role of the nervous system in gait, as well as its adaptation and compensatory mechanismsThis research was funded through the Premio del Ilustre Colegio Profesional de Fisioterapeutas de la Comunidad De Madrid, prize number ICPFM-IX-201

A review of the effectiveness of lower limb orthoses used in cerebral palsy

To produce this review, a systematic literature search was conducted for relevant articles published in the period between the date of the previous ISPO consensus conference report on cerebral palsy (1994) and April 2008. The search terms were 'cerebral and pals* (palsy, palsies), 'hemiplegia', 'diplegia', 'orthos*' (orthoses, orthosis) orthot* (orthotic, orthotics), brace or AFO

A Study to Assess the Effectiveness of Rhythmic Auditory Stimulation along with Neurodevelopmental Therapy in improving the Gait Pattern of Post Stroke patients

INTRODUCTION: Gait restoration after stroke is a major concern of neurological rehabilitation. Stroke is the major cause of disability and raising mare number of handicaps in this industrialized world. In India thy rate of people affected by stroke is keep on increasing because of poor life style and other major factors. The need of rehabilitation after stroke places an important role to make the patient functionally independent in all aspect of basic life style. Physiotherapist is one of the team members who treat the patient in gross motor aspect. AIM OF THE STUDY: The aim of the study is to find the efficacy of combined treatment (Rhythmic auditory stimulation and Neuro Developmental Treatment approach) in improving the gait pattern of post stroke patient. MATERIALS AND METHODOLOGY: MATERIALS: Couch, Foot stool, Blocks\steps, Chalk, Inch tape, Ramp. METHODOLOGY: Study Design: Pre test – Post test experimental study design. Study setting: Health Care Institutes approved by college and Guide. Sampling Method: Simple random sampling method. Sample size: A total number of 10 subjects diagnosed as stroke were taken for the study. Study Duration: The study was conducted for a period of 3 months. Inclusion criteria: • Age 40 to 65 years. • Sex – both male and female. • Able to walk 10 meter independently. • Hemiplegia due to cerebrovascular accident of more than 3 months duration. Exclusion criteria: • Cerebellar ataxia. • Impaired cognitive function. • Aphasia. • Basal ganglion lesion. • Unconscious patient. • Condition that affect mobility like arthritis disease, spinal abnormalities (or) any amputations. • Communicative disorder. RESULT: The most common cause for stroke is due to occlusion of one of the major cerebral artery especially anterior cerebral artery. The stroke patient has reduced functional mobility and reduced leg function and spasticity. Deana and Richards (2000) suggested that rhythmic auditory stimulation along with NDT training had a greater contribution in improving the lower limb extensor muscles after the intervention. At thighs-off, the centre of the body mass has moved forward over the feet. This position ensures that the relative position of body segment at thighs-off enables lower limb extensor forces to accelerate the body vertically into the standing position. (Carr 2009). Stepping up and down in difference direction (forward and sideways) strengthen difference synergic relationship between hip, knee, ankle extensor and hip abductors or adductors to train in different pattern muscles activation and flexible walking performance. (Shepherd 2000). Repetitive stepping exercise using of various steps of various heights increase the strength in the lower extensor muscle. Reaching forward, sideways and in different direction help the individual regain strength and control of the lower limbs, which may enable them to take more weight through the affected leg. Therefore there is mounting evidence that progressive resistance training is effective in improving gait pattern following stroke. CONCLUSION: The study concluded that was the rhythmic auditory stimulation along with NDT effective treatment for improving gait pattern in stroke patients. And also step length and stride length test could be used as the assessment tool for stroke patients