Incidence and risk factors for symptomatic spinal epidural haematoma following lumbar spinal surgery

Spinal epidural haematoma (SEH) is a common complication after lumbar spinal decompression surgery, and symptomatic SEH usually causes devastating neurological deficits. Although different risk factors for post-operative SEH have been reported, few studies focused on patients' laboratory tests. The purpose of this study was to analyze the incidence of symptomatic SEH following lumbar spinal surgery, as well as identify the risk factors for it.

Patients who underwent posterior lumbar spinal decompression surgery between January 2010 and August 2016 were included in this study and their medical records were retrospectively reviewed. Those who developed post-operative symptomatic SEH after the surgery were identified. The risk factors for SEH were analyzed by univariate and multivariate regression analysis.

In total, 2715 patients were included in this study and 31 (1.14%) were identified with post-operative symptomatic SEH. Of these patients, 19 were males and 12 were females, with an average age of 59.39 ± 11.66 years. After multivariate logistic regression analysis, low serum calcium level (P = 0.025), blood type A (P = 0.04), increased estimated blood loss (P = 0.032), prolonged surgical duration (P = 0.018), and decreased post-operative globulin (P = 0.016) were identified as the independent risk factors for post-operative SEH following lumbar spinal surgery. Furthermore, prolonged surgical duration (odds ratio = 3.105) was the strongest risk factor for SEH.

Based on a large population investigation, the incidence of symptomatic SEH following lumbar spinal decompression surgery was 1.14%. Blood type A, increased estimated blood loss, and prolonged surgical duration were identified as the independent risk factors for post-operative SEH while two new risk factors, including low serum calcium level and decreased post-operative globulin, were firstly identified in this study.