Cervical deformity correction.

Subaxial cervical deformities most often occur in the sagittal plane, primarily as kyphosis. Kyphosis may develop secondary to advanced degenerative disease, trauma, neoplastic disease, or after surgery. Whatever the cause, the development of cervical deformity should be avoided and corrected when appropriate because the greater the deformity, the greater the probability of an associated neurological deficit or chronic pain. Patients usually present with mechanical type cervical pain, with or without neurological deficit (i.e., myelopathy). They may also be relatively asymptomatic. Work-up includes appropriate imaging studies, such as radiographs, including dynamic images, and magnetic resonance imaging or computed tomography myelography. The deformity may be accurately assessed and an appropriate surgical strategy undertaken. Depending on flexibility of the deformity and the presence or absence of facet ankylosis, a dorsal, ventral, or combined approach may be used. All approaches are unique in their ability to correct a deformity and in their associated complications. A comprehensive discussion of each is undertaken.