Introduction: Most posterior cervical decompression is supplemented by instrumentation and fusion in North America. However, laminectomy alone remains a common procedure globally. Results comparing these two interventions are contradictory in the literature. Our objectives were 1) to better define the cervical myelopathy population who are treated with a decompression alone in Canada; 2) to assess the outcomes of patients treated with a decompression alone and 3) to compare their outcomes to a cohort of posterior decompression and fusion patients.
Methods: The Canadian Spine Outcomes and Research Network (CSORN) is a multicenter national prospective registry. Patients with CSM who underwent laminectomy alone as their index surgery were identified. Clinical, surgical and radiological data were extracted at baseline and post-operatively. Primary outcome was the Neck Disability Index (NDI) at 1 year. Secondary outcomes included reoperation, SF-36, post-operative cervical alignment, neck and arm pain and satisfaction at 1 year.
Results: From the 274 patients enrolled in the registry, 34 met inclusion criteria. The mean age was 66.12 years and 28 (82.4%) were males. The mean mJOA at baseline was 13.15 and the mean Cobb angle (C2-7) was -7.70° (lordotic). These two baseline parameters were significantly different from the rest of the cohort (240 patients) who underwent posterior instrumentation with a mJOA of 11.82 and a Cobb angle of 2.57°. The number of levels involved (3.77 vs 2.06), the operative time (174 vs 102 min) and the estimated blood loss (330 vs 184 ml) were significantly higher in the instrumented group. At 12 months, there was no significant difference for NDI mean change between laminectomy alone (-14.07) and laminectomy with fusion (-11.90). There was also no difference at one year for mean change in mJOA and SF-36.
Conclusion : In this population of Canadian patients who underwent posterior surgery for CSM, patients selected for a laminectomy alone had a better mJOA score and a more lordotic alignment at baseline. Laminectomy alone involved less decompressed levels, shorter operative time and decreased blood loss. The improvement in mJOA and PROs was not different at one year post-operatively. In a carefully selected population, a simple decompression is a good treatment alternative.
