Prognosis of posterior osteophyte after anterior cervical decompression and fusion in patients with cervical spondylotic myelopathy using three-dimensional computed tomography study.

Abstract

Inadequacy of posterior osteophyte resection in anterior cervical decompression and fusion (ACDF) surgery has long been a clinical concern as it may influence surgical outcome. There has been no agreement on the prognosis in the presence of remnant posterior osteophytes. This study retrospectively investigated 26 cervical spondylotic myelopathy patients after ACDF in whom a remnant posterior osteophyte was identified by long-term follow-up CT scans (minimum of 2years). Remnant posterior osteophytes and osseous spinal canal were measured and compared between pre-operation CT and long-term post-operation CT. The post-operative clinical outcomes were also studied. The remnant osteophytes did not obviously decrease in size in any patient and significantly enlarged in 10 patients, with a new posterior osteophyte developing in one patient. In patients whose remnant osteophyte is enlarged, the incidence of pseudoarthrosis, as well as clinical deterioration during follow-up was significantly higher than patients with stable osteophytes. Contrary to previous reports, none of the remnant posterior osteophytes decreased obviously in size during follow up. Despite the persistence of posterior osteophytes, ACDF is still effective in CSM treatment. Posterior osteophyte enlargement at fused segment appears to be associated with symptomatic pseudoarthrosis and clinical deterioration after surgery.