Effect of Thrombin-Containing Local Hemostatics on Postoperative Spinal Epidural Hematoma in Biportal Endoscopic Spinal Surgery.

STUDY DESIGN: Retrospective case-control study.

PURPOSE: This study aimed to investigate the preventive effect of thrombin-containing local hemostatics (TCLH) on postoperative spinal epidural hematoma (POSEH) in biportal endoscopic spinal surgery (BESS). This study compared the incidence of morphometric and symptomatic POSEH with or without TCLH in BESS.

OVERVIEW OF LITERATURE: POSEH is reported not uncommon in BESS when compared with conventional spine surgery (CSS). TCLH achieves hemostasis with a high success rate in CSS. However, few studies have examined the effect of TCLH on BESS.

METHODS: Patients with and without TCLH were assigned to groups A and B, respectively. POSEH between the two groups was compared morphometrically and symptomatically. The risk factors for symptomatic and morphometric POSEH in BESS were identified.

RESULTS: The morphometric POSEH was greater in group B, and the difference was significant (p =0.019). The incidence of symptomatic POSEH was lower in group A with 4.6% (5/109) than in group B with 9.5% (9/95); however, the rate was not significantly different (p =0.136). The morphometric POSEH was classified into two small (hG1 and hG2) and large (hG3 and hG4) and were compared between groups A and B, and the difference was significant (p =0.02). In the multivariable logistic regression, nonuse of TCLH (p =0.004) and preoperative diagnosis of stenosis (p =0.016) were variables found to be significant risk factors of morphometric POSEH.

CONCLUSIONS: Severe compression of the thecal sac by POSEH is more common in patients without TCLH. The risk of hematoma formation was higher when bilateral decompression was needed and the cut bone surface was more exposed.