Pattern of premature degenerative changes of the cervical spine in patients with spasmodic torticollis and the impact on the outcome of selective peripheral denervation

Objectives-To characterise the pattern of and risk factors for degenerative changes of the cervical spine in patients with spasmodic torticollis and t o assess whether these changes affect outcome after selective peripheral de nervation. Methods-Preoperative CT of the upper cervical spine of 34 patients with spa smodic torticollis referred for surgery were reviewed by two radiologists b linded to the clinical findings. Degenerative changes were assessed for eac h joint separately and rated as absent, minimal, moderate, or severe. Patie nts were clinically assessed before surgery and 3 months postoperatively by an independent examiner using standardised clinical rating scales. For com parison of means a t test was carried out. To determine whether an associat ion exists between the side of degenerative changes and type of spasmodic t orticollis a ill test was used. Changes in severity, disability, and pain b efore and after surgery were calculated using a Wilcoxon matched pairs sign ed ranks test. Results-Fourteen out of 34 patients had moderate or severe degenerative cha nges. They were predominantly found at the C2/C3 and C3/C4 level and were s ignificantly more likely to occur on the side of the main direction of the spasmodic torticollis (p=0.015). There was no significant difference in age , sex, duration of torticollis, overall severity, degree of disability, or pain between the group with either no or minimal changes and the group with moderate or severe changes. However, in A the second group the duration of inadequate treatment was longer (10.1 v 4.8 years; p=0.009), head mobility was more restricted (p=0.015), and head tremor was more severe (p=0.01). A t 3 months postoperatively, patients with no or minimal degenerative change s showed a significant improvement in pain and severity whereas no differen ce was found in those with moderate or severe changes. Conclusions-Patients with spasmodic torticollis have an increased risk of d eveloping premature degenerative changes of the upper cervical spine that t end to be on the side towards which the head is turned or tilted and compro mise outcome after surgery. Effective early treatment of spas-medic tortico llis with botulinum toxin seems to have a protective effect. Patients with spasmodic torticollis and restricted head mobility who do not adequately re spond to treatment should undergo imaging of the upper cervical spine. Pati ents with imaging evidence of moderate or severe degenerative changes seem to respond poorly to selective peripheral denervation.