Cervical spondylolysis.

The term cervical spondylolysis describes a long-standing, perhaps congenital defect of the pars interarticularis of a cervical vertebra. We report 10 new cases of cervical spondylolysis and review the literature. All patients in this report were treated nonoperatively with subsequent symptomatic improvement. Cervical spondylolysis must be differentiated from its traumatic counterparts radiographically. Characteristic radiographic findings include well-corticated margins at the defect, a characteristic "bow tie" deformity, and ipsilateral dysplastic facets. Compensatory hypertrophic changes of the adjacent articular processes, spina bifida, and spondylolisthesis are frequently, but not always, seen in conjunction with cervical spondylolysis. The vast majority of patients with radiographically proven cervical spondylolysis can be treated confidently with conservative measures. Surgical intervention should be reserved for those who fail nonoperative management or who exhibit neurologic compromise referable to an unstable spondylolytic defect.