Delayed hyper-reactivity to metal ions after cervical disc arthroplasty: a case report and literature review.

Study Design: Anecdotal case report.

Objective: To report a very interesting and perplexing complication of cervical total disc arthroplasty that has not been previously reported in literature.

Summary Of Background Data: Although there has been increasing interest in the field of artificial disc replacement to treat cervical degenerative disc disease, not much has been mentioned in the literature about the potential complications of the disc itself. We encountered a delayed complication in 1 patient that has not been reported in the literature.

Method: Thirty-nine-year-old white woman received total disc arthroplasty for herniated intervertebral disc at C5-C6 level uneventfully. She had recurrence of symptoms 9 months after the procedure and failed to respond to conservative measurements. Imaging revealed soft tissue mass posterior to the implanted disc encroaching the spinal cord.

Results: Surgical explantation and exploration of the disc space revealed thick layer of abnormal hyaline cartilaginous tissue with chronic inflammatory debris. The patient had complete resolution of symptoms after the revision surgery.

Conclusion: Although there is increased enthusiasm about motion preservation technology and disc replacement surgery for intervertebral disc herniation, unexpected complications like the present case need to be shared within the scientific community to better understand the risks associated with these new and promising devices.