Objective evaluation of selective peripheral denervation for spasmodic torticollis

The authors evaluated the results of selective peripheral denervation (SPD) of posterior rami of the cervical spinal nerves and/or the accessory nerve for spasmodic torticollis. Five patients underwent seven operations in total and the results were evaluated with the modified Tsui's score which was used in the clinical trial of botulinum toxin (BTX) for torticollis in Japan. The preoperative score was 10.8 ± 2.2 (mean ± S.D.) and the postoperative score was 1.4 ± 1.7. The score changes indicated the effects of the operation as 'excellent' in four cases and 'good' in one case. These results indicate that SPD is superior to BTX in terms of control of symptoms in spasmodic torticollis. After the initial operation, however, two patients showed the so-called 'mole-hitting game phenomenon' in which normal muscles develop abnormal contraction after denervation of abnormal muscles. This forced us to perform the second operations. Although this phenomenon was first described in botulinum toxin treatment, this is probably the first report in surgically denervated cases.