Movement disorders following nonfunctional neurosurgery

Object. Knowledge is scarce about movement disorders that follow neurosurgical operations other than functional stereotactic surgery. The cases of 14 patients who suffered from movement disorders secondary to craniocerebral or spinal surgery are analyzed. None of these patients was initially treated by any of the authors. Methods. Twelve patients underwent surgery for cerebral diseases. Nine of these patients harbored tumors and three patients had neurovascular disorders. Two patients underwent spinal surgery for cervicothoracic ependymoma or for multiple cervical disc herniations. Twelve of the 14 patients had immediate postoperative side effects such as hemiparesis, ataxia, and somnolence. In all but two patients, movement disorders became manifest only after a delay. Dystonic movement disorders developed in ei ht patients, unilateral tremors in three patients, unilateral facial myokymia in one patient, and hemichorea-hemiballism in two patients. The mean delay of onset for tremor was 5 weeks and that for dystonic movement disorders was 5.5 months. Movement disorders were transient in three patients; however, they were persistent in 11 patients at a mean follow-up period of 5 years. These movement disorders caused marked persistent disability in four patients. Lesions of the contralateral striatum were identified in patients with dystonic syndromes and lesions of the dentatothalamic outflow in patients with tremors. In three patients who had postoperative basal ganglia lesions after partial removal of astrocytomas, tumor regrowth was later documented. Medical treatment in patients with persistent movement disorders rendered only limited benefit. Two patients improved with botulin injections. In one patient postoperative hemidystonia was alleviated by contralateral thalamotomy. Conclusions. Dystonic syndromes and tremors are the most common movement disorders that occur after craniocerebral and spinal surgery. Postoperative movement disorders can lead to various degrees of functional disability. The pathoanatomical correlations are similar to those described in other patients with secondary movement disorders.