Comparative study of the prevalence of venous thromboembolism after elective spinal surgery.

To the authors' knowledge, no comparative studies exist of venous thromboembolism (VTE) based on different pathologies, surgical procedures, or spinal levels after spinal surgery. The authors prospectively investigated VTE after elective spinal surgery. The study comprised 4 patient groups. Group 1 comprised 79 patients with lumbar spinal stenosis treated with posterior decompression without fusion; group 2 comprised 90 patients with lumbar or lower thoracic degenerative disease treated with instrumentation for spine fusion; group 3 comprised 89 patients with cervical degenerative disease treated with posterior decompression or instrumentation for fusion; and group 4 comprised 82 patients with spinal tumors treated with total spondylectomy or piecemeal excision with stabilization. Deep venous thrombosis (DVT) and pulmonary thromboembolism (PTE) screening was performed for all 340 patients 7 to 10 days postoperatively. Binomial logistic regression analysis was used to assess the association of risk factors. The incidence of VTE was 15.2% in group 1, 13.3% in group 2, 4.5% in group 3, and 22.0% in group 4. The overall incidence of PTE was 2.9% (10/340 patients). Of the 10 cases of PTE, 2 were symptomatic and 8 were asymptomatic. No DVT occurred in 6 of 10 PTE-positive patients. Multivariate analysis showed that spinal tumors, neurologic deficits, and advanced age were risk factors for VTE. Spinal tumor surgery carries a high risk of critical VTE, whereas cervical spine surgery carries a low risk. No DVT occurred in 60% of PTE-positive patients. This result indicates that screening for PTE is also needed in patients who are at high risk for VTE.