Time-course and determinants of spasticity during the first six months following first-ever stroke

To explore the occurrence of, and risk factors for, spasticity until 6 months after first-ever stroke.

Forty-nine patients were examined at day 2-10, at 1 month, and at 6 months. The modified Ashworth Scale was used to assess resistance to passive movements. A comprehensive clinical examination was performed to identify other positive signs of upper motor neurone syndrome, in accordance with a broader definition of spasticity, and to evaluate whether spasticity was disabling. Neurological impairments were determined by use of the National Institutes of Health Stroke Scale and global disability by use of the modified Rankin Scale.

Spasticity was present in 2 patients (4%) at day 2-10, in 13 patients (27%) at 1 month, and in 11 patients (23%) at 6 months. Severe paresis of the arm at day 2-10 was associated with a higher risk for spasticity at 1 month (odds ratio = 10, 95% confidence interval 2.1-48.4). Disabling spasticity was present in one patient at 1 month and in 6 patients (13%) at 6 months.

Spasticity according to the modified Ashworth Scale usually occurs within 1 month and disabling spasticity later in a subgroup. Severe paresis of the arm is a risk factor for spasticity.