Current uses of open phenol nerve block for adult acquired spasticity.
Forty-nine open phenol nerve injections were performed for acquired spasticity during a five-year period. The most common etiology of acquired spasticity was closed head injury (70%). Thirteen phenol injections to the musculocutaneous nerve were performed for excessive elbow flexion. The immediate results were absence of biceps and brachialis muscle activity, and an average gain of 43 degrees in extension. The effects of the nerve block subsided within six months. Nine nerve blocks were followed for more than one year. In two patients the upper extremities were almost normal. In the remaining seven the upper extremities were nonfunctional. Twenty-eight phenol injections to the posterior tibial nerve were performed for uncontrolled excessive plantar flexion and/or fixed equinus. The immediate result was cessation of gastrocnemius and soleus activity. Twenty-seven ankles attained a neutral position. The effects of the nerve block subsided within six months. Thirteen patients with 19 blocks were followed for more than eight months. Nine patients underwent lengthening of the Achilles tendon and six patients required orthotic devices for control of plantar flexion spasticity. In general, patients with acquired spasticity who require open phenol nerve blocks are unlikely to have normal functioning extremities when the effects of the nerve block have subsided.