Degenerative Scoliosis

LEARNING OBJECTIVES: After participating in this activity, the surgeon should be better able to: 1. Assess and diagnose patients with degenerative scoliosis. 2. Select appropriate diagnostic imaging modalities for patients with suspected degenerative scoliosis. 3. Formulate a treatment plan for these complex patients. B y definition, a lateral curvature of the spine greater than 10 degrees is considered a scoliotic deformity.1 However, better understanding of the anatomy of the spine and improved imaging techniques have shown that, in addition to the coronal imbalance, there is also an associated malrotation of the spine and loss of sagittal balance.2 Thus, scoliosis is a complex three-dimensional rotational deformity that affects the spine in the coronal, sagittal, and axial planes.2 Adult degenerative or de novo scoliosis is generally thought to develop as the result of asymmetric degeneration of discs.3 Adult degenerative scoliosis may also result from unarrested adolescent idiopathic scoliosis that degenerates as the patient ages. In most cases, nonoperative treatment is sufficient to relieve pain and restore patients to their normal activities. In severe cases, surgical treatmentmay be necessary after all nonoperative measures have been exhausted. However, surgical treatment for patients with degenerative scoliosis can be risky, as these patients are older and may have medical comorbidities that lead to complications during surgery or during recovery. In 1968, the complications associated with surgical correction of adult deformity were estimated to include a 5% risk of death and 40% risk of a major medical complication.4 Advances in surgical and anesthetic techniques, neurophysiologic monitoring, and improvements in perioperative management have significantly reduced these risks.5 In this review, readers learn how to assess patients with degenerative scoliosis and treat these complicated cases.