Article

Objective: To determine whether spasticity in persons with spinal cord injury (SCI) is associated with elevated monosynaptic reflex excitability. Design: One-way experimental. Setting: Research laboratory. Participants: Convenience sample of 9 subjects (8 men, I woman) with chronic and complete SCI and 20 persons (14 men, 6 women) with no neurologic impairment. Subjects with SCI exhibited lower-extremity spasticity as indicated by velocity-dependent increased resistance to passive muscle stretch, abnormally brisk deep tendon reflexes, involuntary lower-extremity flexion and/or extension spasms, and clonus. Intervention: Soleus H-reflex recruitment curves were elicited in all subjects. Main Outcome Measures: Soleus H-reflex threshold (HTH), gain (HGN), and amplitude (HPP). Results: There was no difference between subjects with and without SCI in HTH, HGN, or HPP. Conclusions: Spasticity in people with chronic and complete SCI was not associated with increased excitability of the connections between la afferent projections and motoneurons. Factors extrinsic to these connections may have a role in spasticity caused by SCI.

Langue : ANGLAIS