Somatosensory impairment after stroke: frequency of different deficits and their recovery

OBJECTIVE: To investigate the frequency of somatosensory impairment in stroke patients within different somatosensory modalities and different body areas, and their recovery. DESIGN: Prospective observational study. SETTING: Two stroke rehabilitation units. SUBJECTS: Seventy patients with a first stroke (36 men, 34 women; average age, 71, SD 10.00 years; average time since stroke onset, 15 days) were assessed on admission and two, four and six months after stroke. INTERVENTIONS: Not applicable. MAIN MEASURE: Nottingham Sensory Assessment. RESULTS: Somatosensory impairment was common after stroke; 7-53% had impaired tactile sensations, 31-89% impaired stereognosis, and 34-64% impaired proprioception. When comparing somatosensory modalities within body areas the kappa values were low (kappa values<0.54). Recovery occurred over time, though not significantly in lower limb tactile sensations. Stroke severity was the main factor influencing initial somatosensory impairment, but accounted for a small amount of the variance (21-41%). Initial somatosensory impairment was significantly related to somatosensory ability at six months, accounting for 46-71% of the variance. CONCLUSIONS: Proprioception and stereognosis were more frequently impaired than tactile sensations. The different somatosensory modalities showed only slight agreement between impairment within the same body areas, suggesting that the modalities are independent of each other and all should be assessed. High agreements were found between different body areas for each somatosensory modality. Somatosensory impairment was associated with stroke severity, however low variance indicated other factors were involved.