Treatment of upper extremity spasticity in stroke patients by focal neuronal or neuromuscular blockade: a systematic review of the literature.

Studies published from January 1966 until October 2000 on the clinical effects of focal neuronal and neuromuscular blockade in post stroke upper limb spasticity were identified. Twelve studies were included and evaluated on 13 methodological criteria. Ten studies on Botulinum toxin type A (BTX-A) treatment were found (of which 4 were randomised controlled trials (RCTs) and 6 were uncontrolled observational studies) as well as one uncontrolled observational study on phenol blockade of the subscapular muscle and one on alcohol blockade of the musculocutaneus nerve. The homogeneity of the patient groups with regard to diagnosis and their comparability with regard to functional prognosis and other sources of bias were generally unsatisfactory. Only two RCTs met predetermined criteria of minimal validity. There is evidence of effectiveness of BTX-A treatment on reducing muscle tone (varying between 0.8 and 2.0 points on the modified Ashworth scale) and improving passive range of motion at all arm-hand levels in chronic stroke patients for approximately 3-4 months. There is also preliminary evidence of a synergistic effect of concomitant electrostimulation. Taking into account a critical maximum dose of 100 MU Botox" (300-500 MU Dysport) for preserving active finger flexion, BTX-A treatment seems to be a safe focal spasmolytic treatment. Effectiveness of BTX-A treatment on improving functional abilities could not be convincingly demonstrated, although two subgroups may be identified that might specifically benefit at a functional level: (1) patients with mild spasticity and a potential for voluntary extensor activity and (2) patients with severe spasticity suffering from problems with positioning and taking care of the affected arm and hand. Larger controlled studies are needed to compare the effectiveness of BTX-A with other focal spasmolytic techniques paying special attention to individual goal assessment, the (duration of) functional benefits, co-treatment and aftercare, side-effects and cost-effectiveness.