Congenital double-level cervical spondylolysis: a case report and review of the literature

Purpose: We report a rare Japanese female who was affected with three genetic-linked diseases: double-level cervical bilateral spondylolysis in association with spina bifida occulta, cleft lip and monostotic fibrous dysplasia of the right proximal femur. The case was considered to be congenital in origin. We also review the pertinent literature of cervical spondylolysis, with a focus on the pathogenesis of multiple-level cervical spondylolysis. Methods: A 40-year-old female presented with progressive clumsiness and numbness of the hands. Japanese Orthopedic Association (JOA) score for the cervical spine was 14.5. Plain radiographs of the cervical spine showed bilateral spondylolysis of the articular mass portion, with an adjacent dysplastic change and spina bifida occulta of C4 and C5. Cervical laminoplasty from C4 to C6 was performed. Results: The postoperative course was uneventful, and the patient had some recovery of muscle power and sensation, with JOA score improving to 15.5. At the 8-year follow-up, the patient had no recurrence of symptoms, but did show kyphotic and degenerative changes at the C4/5 and C5/6 level with no apparent instability. Conclusions: This case is a rare presentation of bilateral cervical spondylolysis involving C4 and C5, presumably congenital, accompanied by combined dysplastic changes of the cervical spine, cleft lip, and fibrous dysplasia, possibly through an error involving an ossification center during the embryonic stage.