SPASTICITY AND MUSCLE CONTRACTURE FOLLOWING STROKE

It has become increasingly recognized that the major functional defici ts following brain damage are largely due to 'negative' features such as weakness and loss of dexterity rather than spasticity A variety of studies suggest that spasticity is a distinct problem and separate fro m the loss of dexterity, but that it may be implicated in the formatio n of muscle contracture and even in the recovery of strength. In order to address these issues, we examined the relationship between spastic ity, contracture, strength and dexterity in the affected upper limb fo llowing stroke. Spasticity was measured both as increased tonic stretc h reflexes and increased resistance to passive stretch (hypertonia). T wenty-four patients were recruited non-selectively from three rehabili tation units within 13 months of their stroke. Few patients exhibited increased tonic reflexes but half were found to have muscle contractur e, the earliest at 2 months following stroke. Hypertonia was associate d with contracture but not with reflex hyperexcitability. Increased to nic stretch reflexes were observed only In a subgroup of those with co ntracture and where present could usually be elicited only at the end of muscle range. This finding suggests that instead of spasticity caus ing contracture, contracture may actually potentiate spasticity in som e patients. However; the majority of patients with contracture did not have increased tonic stretch reflexes. In addition, we found no relat ionship between spasticity and either weakness or loss of dexterity. T herefore, while hypertonia remains an important problem following cere bral lesions, it would appear that the amount of attention directed to reflex hyperexcitability associated with spasticity is out of proport ion with its effects. Consequently, hypertonia needs to be clearly dis tinguished from reflex hyperexcitability in patients with spasticity.