Selective Muscle Release Followed by Anterior Body Fusion for Cervical Myelopathy Associated with Torsion Dystoni

The torsion dystonia is a rare disorder resembling athetosis characterized by abnormal involuntary movements and postures produced by muscle spasm. In patients with athetosis, cervical radiculopathy or myelopathy often occurs during adult life. However, we experienced a patient who had cervical radiculomyelopathy associated with torsion dystonia. In 1996, a 54 years old female visited our hospital due to gait disturbance and pain in the right upper extremity associated with involuntary movements of her head and neck. Her symptoms first appeared at the age of four, which gradually aggravated and she was diagnosed as idiopathic torsion dystonia by neurologist.Neurological examination showed cervical radiculomyelopathy. Radiographs and imaging investigations revealed instability, degenerative changes and compression of spinal cord at the C3/4 level. Initially, we followed Matsuo's method by releasing selective muscles to minimize the involuntary movements. As a second step, two months later, anterior body fusion at C3/4 level was carried out. Her cervical spine was immobilized with halo vest for 6 weeks without any inconvenience. Bone union was achieved by 6 months postoperatively and her symptoms were decreased.In cervical radiculomyelopathy associated with abnormal involuntary movement, cervical fusion operation following selective muscle release is an effective surgical option.