Scoliosis and Friedreich’s Ataxia: The Experience at One Institution

Summary: Friedreich's ataxia is a genetically transmitted, progressive spinocerebellar degenerative disease characterized by ataxia with a high rate of scoliosis (54%) many of which go onto spinal fusion (37.5%). Curve patterns were variable, but 40% of thoracic curves were left-sided. Bracing was of questionable benefit. Using modern instrumentation techniques, deformity correction can be achieved and maintained.

Purpopse: Friedreich's ataxia is a genetically transmitted, progressive spinocerebellar degenerative disease characterized by ataxia. We reviewed the 50-year history of treating Freidriech's ataxia and scoliosis at our pediatric center.

Methods: Following IRB approval, chart review of Friedreich's ataxia patients identified those having scoliosis. Demographic data, time of follow-up, brace treatment, operative treatment, and complications were determined. Radiographic review was also performed.

Results: 59 patients were identified as having Friedreich's ataxia, of which 32 (54%) were diagnosed with scoliosis. 18 were male, 14 were female. Mean age at diagnosis of scoliosis was 13 years (5-17 years). Mean follow-up was 3.9 years (0-13 years). There were 12 (38%) double major curves, with 12 (38%) of the thoracic curves being left sided. Hyperkyphosis was present in 7 (22%). 21 (66%) of patients progressed _6 degrees. Seven (21.8%) patients were treated in braces with average progression in brace of 15 (-5-44) degrees. 12 (37.5%) patients were treated with spinal fusion (11 PSF and 1 ASF). SSEP monitoring was attempted in eleven patients, but was effective in only one. The immediate post-operative correction was 50% (24- 87%) in the thoracic curve. Final correction averaged 40% (-22-85%) in the thoracic curve. One patient (8.3%) developed an infection and was the only patient who underwent re-operation.

Conclusions: Scoliosis in Friedreich's ataxia is common (54%). Curve patterns are variable, and do not necessarily resemble idiopathic curves. Although few patients were braced, results were equivocal. Fusion using modern hook/rod constructs was effective in creating substantial intra-operative correction and maintaining correction postoperatively. SSEP monitoring was usually ineffective, so preparation for a wake-up test is recommended.

Significance: Patients with Friedreich's ataxia need to be carefully screened for scoliosis and counseled about the high rate of surgical fusion. Using modern implants, correction can be achieved and maintained.