To Örebro University

STUDY DESIGN: Retrospective analysis of prospectively collected data from the National Swedish Spine Register (Swespine).

OBJECTIVE: To evaluate the effects of symptomatic spinal epidural hematoma (SSEH) requiring reoperation on one-year patient-reported outcome measures (PROMs) in a large cohort of patients treated surgically for lumbar spinal stenosis (LSS).

SUMMARY OF BACKGROUND DATA: Studies exploring the outcomes of reoperations after SSEH are scarce and often lack validated outcome measures. As SSEH is considered a serious complication, understanding of the outcome following hematoma evacuation is important.

MATERIALS AND METHODS: After retrieving data from 2007 to 2017 from Swespine, we included all patients with LSS without concomitant spondylolisthesis who were treated surgically with decompression without fusion. Patients with evacuated SSEH were identified in the registry. Back/leg pain numerical rating scales (NRS), the Oswestry Disability Index (ODI), and EQ VAS were used for outcome assessment. PROMs before and one-year after decompression surgery were compared between evacuated patients and all other patients. Multivariate linear regression was performed to determine if hematoma evacuation predicted inferior one-year PROM scores.

RESULTS: A total of 113 patients with an evacuated SSEH were compared with 19527 patients with no evacuation. One-year after decompression surgery, both groups showed significant improvement in all PROMs. When comparing the two groups' one-year improvement there were no significant differences in any PROM. The proportion of patients achieving the minimum important change was not significantly different for any PROM. Multivariate linear regression found that hematoma evacuation significantly predicted inferior one-year ODI (β=4.35, P=0.043), but it was not a significant predictor of inferior NRS Back (β=0.50, P=0.105), NRS Leg (β=0.41, P=0.221), or EQ VAS (β=-1.97, P=0.470). CONCLUSIONS: A surgically evacuated SSEH does not affect outcome in terms of back/leg pain or health-related quality of life. Commonly used PROM surveys may not capture neurologic deficits associated with SSEH.