[Soleus muscle reflexes evoked by stimulation of the posterior tibial nerve compared to tendon reflexes in man (author's transl)]

Abstract

The characteristics of the reflex response evoked in the soleus muscle after stimulation of the posterior tibial nerve at the ankle were contrasted with the achilleus tendon reflex in 14 healthy volunteers and in a group of selected neurological patients. The following features were examined: conditions of stimulation including stimulation frequency; appearance of reflex activity in muscles other than soleus, effect of the vibratory stimulation, interactions with voluntary contraction. Moreover, a reflex response is described in the soleus following stimulation of the sural nerve. The results have shown a marked jitter in latencies of the responses, a pattern of coactivation of antagonistic muscles, a clear increase of amplitude under vibration or voluntary contraction, normal responses both in spasticity and in S1 radiculopathy with achilleus areflexia. All these data differ from those observed with the tendon jerk of the same amplitude and differentiate the two responses. It is concluded that the reflex evoked by stimulation of the tibial nerve at the ankle is a polysynaptic response of cutaneous origin.