Adduction contracture of the thumb in cerebral palsy. A preoperative electromyographic study.

In twenty-three patients with cerebral palsy and functional spastic hemiplegia, the contracted thenar-adductor space of the involved hand was evaluated by electromyography. The needle electromyogram was used to determine if the patient had selective control of the adductor muscle. In eight patients only partial myotomy of the adductor muscle during z-plasty of the web was performed because selective control of that muscle was present during either grasp or release. In four patients a complete release was done, and in two of them the ability to pinch was impaired.