Cervical arthroplasty in the management of spondylotic myelopathy: 18-month results.

OBJECT: Cervical spinal cord compression managed via an anterior approach with an arthrodesis may be associated with a decreased range of motion and accelerated adjacent-segment degeneration. Artificial cervical disc replacement may address these problems.
METHODS: The author presents a series of 11 patients (seven men and four women, ages 31-55 years) with anterior cervical decompression and placement of a total of 15 artificial disc prostheses. Clinical and radiological follow-up review was performed at 24 hours, 6 weeks, 3 months, 6 months, and then yearly (mean follow-up period 18.4 months, range 10-32 months). There were no major complications. There was an improvement in the Nurick grade by 0.91 grades (p < 0.001) and in the Oswestry Neck Disability Index by 41.5 percentage points (p < 0.001). In one case fusion was attained at 17 months postoperatively and one patient had a transient worsening of preoperative symptoms postoperatively, with focal kyphosis. The spinal cord was decompressed on postoperative imaging in all cases.
CONCLUSIONS: Cervical arthroplasty after anterior cervical decompression at one or more levels represents an exciting tool in the management of spinal cord compression caused by spondylotic disease or acute disc prolapse. Results obtained in this study add further weight to the potential role of cervical arthroplasty for cervical myelopathy and longer follow up is provided on a previously reported series. It is suggested that care must be taken in using this unconstrained prosthesis if there is a preexisting spinal deformity. Longer follow up will reveal any delayed problems with artificial disc implantation, but in the short to medium term, this technique offers an excellent outcome.