Recovery of motor functions following hemiparetic stroke: a clinical and magnetic resonance-morphometric study

Predictors for the degree of clinical recovery after stroke are still poorly defined. In this study we tried to assess the predictive value of clinical data and of lesion size for motor recovery after ischemic stroke. In 52 hemiparetic patients we monitored the course of clinical recovery by a dedicated score of sensorimotor hand function after their first stroke. The course of the lesion size was measured in proton density magnetic resonance images. Three groups of patients were identified. Patients with moderate initial motor deficit recovered almost completely within 9 days (17/17, group 1). From the patients with severe initial motor deficit, about equal numbers recovered (16/35, group 2) or remained severely impaired during the entire observation period of more than 6 months (19/35, group 3). There was no correlation between changes of lesion size and motor deficit. Logistic regression of probability of good clinical outcome on initial lesion size, initial motor score and subcortical versus cortical location of lesion showed that only the initial motor score was predictive (p = 0.006). A relative improvement of the initial motor score of about 20% in the first 4 weeks after stroke appeared to be a relevant cut point for good outcome. The data indicate that patients with mild initial motor deficits recover well, whereas severely affected patients may differ in outcome. Since lesion size was not correlated with outcome the amount of spared residual function appeared as major determinant for the capacity for motor recovery.