Hand and arm coordination during reach to grasp after stroke

The research explores kinematic impairments of reach to grasp in patients with lesions involving the parietal cortex and cerebellum; brain areas considered important for controlling hand and arm coordination. The effectiveness of current targeted interventions is reviewed and a novel intervention tested in a proof of concept pilot study. The first study demonstrates that even though movements of people with parietal lobe and cerebellar lesions are characterised by prolonged duration and longer trajectories, coordination, expressed by correlation between kinematic features of transport and grasp, is comparable to controls. Coordination is also largely preserved after perturbations to the transport component. Slower movements, potentially controlled by other brain areas may compensate for latent impairments in hand and arm coordination. A systematic review identifies functional therapy, electrical stimulation and robot training as potential interventions for improving hand and arm coordination after stroke. However, insufficient evidence and heterogeneity in terms of the stroke population prevents definitive conclusions regarding effectiveness. A second empirical study examines a novel treatment approach by way of treatment targeted towards patients with these specific lesions. The study shows that high intensity, repetitive practice of reach to grasp with auditory rhythmic cueing is well tolerated by a sample of stroke patients with moderate upper limb impairments. Findings such as shorter wrist path trajectories provide early indications for improved motor control during reach to grasp. Results suggest a need for more challenging practice with higher dosage particularly as reach to grasp movements remain prolonged, despite training that emphasizes progression of speed