Pedicle fixation devices in the treatment of adult lumbar scoliosis

Segmental pedicle screw instrumentation in adult lumbar scoliosis allows better curve correction and restoration of lumbar lordosis. In a retrospective study, to assess the value of this fixation, 9 patients treated with the AO Internal Fixator and 18 with Cotrel-Dubousset instrumentation were reviewed. Mean age at surgery was 60 years (range, 40-88), and curves were measured between 22 degrees and 82 degrees. At follow-up (mean of 56 months for the AO Internal Fixator and 42 months for Cotrel-Dubousset instrumentation), the average curve correction was better than 50% Overall satisfactory clinical results with pain relief and improved walking distance were noted in 86% of the patients. Using this technique no postoperative deaths or neurologic deficits occurred. Only a few complications and a 4% pseudarthrosis rate could be observed. Our study shows that the age of the patients with degenerative scoliosis is not a contraindication for major surgery. Meticulous posterior spine release before instrumentation is essential for curve correction and bone fusion. Lumbar lordosis is more easily restored with Cotrel-Dubousset instrumentation, which seems to correspond to the incidence of low back pain. Cases with evident neurologic deficits are best treated by additional nerve decompression.