Postoperative spinal deformity and instability after cervical spinal cord tumor resection in adults: A systematic review and meta-analysis

To investigate the incidence of cervical spine deformity and instability after posterior cervical spinal cord tumor (CSCT) resection without fusion or fixation in adults and examine relevant risk factors by reviewing and summarizing previously reported studies.We selected peer reviewed articles published between January 1990 and December 2020 from the MEDLINE and Cochrane Library databases using relevant key words. Articles in which the authors mainly described spinal cord tumor resection through posterior surgery without fusion or fixation in adults were selected for analysis. Patient's data including age, sex, extensive number of laminectomy levels, laminectomy at C2, C3, or C7, multilevel facetectomy, facet destruction, preoperative cervical kyphosis, and preoperative motor deficit were documented. Comparable factors were assessed using the odds ratio (OR) and weighted mean difference (WMD) of 95% confidence intervals (CI).Among 133 articles identified, 18 met selection criteria. Overall incidence of deformity and instability after CSCT surgery was 0%-41.7% and 0%-20.5%, respectively. Younger age (WMD, -5.5; 95% CI, -10.52 ∼ -0.49; P = 0.03), C2 laminectomy (OR, 5.33; 95% CI, 2.39 ∼ 11.91; P < 0.0001), more laminectomy level (WMD, 2.77; 95% CI, 1.78 ∼ 3.76; P < 0.00001) were identified as risk factors for deformity and instability after CSCT surgery.Patients undergoing CSCT resection should receive careful follow-up for postoperative spinal deformity and instability. Younger age, C2 laminectomy, and more laminectomy level were significantly associated with occurrence of deformity and instability after CSCT surgery. Upfront spinal fixation at the time of resection should be considered in selected patients.