Abstract
INTRODUCTION: Cervical disc replacement (CDR) has become prevalent in the treatment of cervical pathology. CDR is an appealing option for several reasons, including improvement of symptoms, preservation of range of motion, and the absence of risk for nonunion - a complication of an anterior cervical decompression and fusion (ACDF) surgery. In this case series, we explore the use of CDR to treat cervical nonunion. METHODS: Four patients, ages 50 to 64, presented to one surgeon with symptomatic cervical nonunion. Three of the four patients possessed risk factors for further nonunion and were therefore considered especially well-suited to a CDR rather than a revision ACDF. X-ray, MRI, and CT were used to confirm the presence of nonunion and to determine the architectural feasibility of replacing the level with a cervical disc arthroplasty. Six total nonunion levels were present in four patients (two levels in two patients and one level in two patients). Each of the nonunion levels was successfully treated with a revision decompression and CDR. RESULTS: Postoperatively, all four patients experienced improvement of nonunion symptoms. Neck Disability Index improved on average by 75% (preoperative score 51% to postoperative score 13%). Flexion-extension X-rays were available in three patients, which showed an increase in an average range of motion from 2 degrees to 7 degrees at the revised levels. CONCLUSION: The series describing four successful cases expands the current literature and provides support for future investigation into CDR as a treatment for cervical nonunion. We propose CDR as a viable option to treat symptomatic cervical nonunion and restore range of motion in patients without significant arthrosis and with preserved endplate architecture.