The risk-benefit issues and ultimate effects of internal fixation are still under investigation. The deformity may arise from preexisting deformity or may be purely the result of degenerative changes. Multisegmental collapse, facet hypertrophy, and rotational and translational deformities may cause both axial and radicular symptoms. Neural symptoms may be the result of asymmetric pedicular settling, causing traction on the nerve roots on the convex side of the deformity. Alternatively, collapse of the neural foramena on the concave side of the deformity may cause direct nerve root compression.
Radiographs reveal multisegmental collapse, spondylosis, osteoporosis, and hypermobile segments.
Spondylolisthesis may occur concurrently. A broad-based annular bulging should not be misinterpreted as a herniation of disk material. Nonoperative treatment of degenerative scoliosis is often met with failure. Bracing is ineffective in preventing progression and is poorly tolerated.20 Both decompression and fusion are most often indicated, although an occasional unilateral root decompression may be appropriate for patients with nerve root involvement at one or two levels and minimal back discomfort. Back pain is less commonly an indication for surgery.