Reoperation rates following spinal epidural abscess evacuation with and without instrumentation: a retrospective matched cohort analysis.

STUDY

DESIGN

Retrospective cohort study.

OBJECTIVES

The role of concurrent spinal instrumentation during spinal epidural abscess (SEA) evacuation remains a subject of debate, with concerns of infection recurrence and increased rates of reoperation versus the benefit of stability. This study investigates long-term reoperation rates following SEA evacuation with or without posterior instrumentation.

METHODS

The PearlDiver national insurance claims database was queried. Patients undergoing abscess evacuation were identified and stratified into two cohorts: evacuation alone and evacuation with posterior instrumentation. 1:1 matched cohorts were created based on variables significant on multivariable logistic regression analysis. The primary outcome was reoperation rate at 2-years following index surgery. A secondary analysis stratified by procedure type was performed.

RESULTS

6,840 patients were identified who underwent SEA evacuation (5,710 evacuation alone, 1,130 evacuation with instrumentation). 1:1 matching yielded 1,126 patients in each cohort. No significant difference was observed in overall reoperation rate at 2-years (10.1% vs. 11.8%, p = 0.20). Patients with posterior instrumentation had a higher rate of hardware-related reoperations, while patients who received evacuation alone had higher rates of subsequent decompression. Posterior instrumentation itself was not a significant predictor of reoperation (OR = 1.14, p = 0.16). Comorbidities including diabetes, obesity, chronic steroid use, and osteoporosis were associated with increased risk of reoperation.

CONCLUSIONS

This is the largest study investigating reoperation rate following SEA evacuation with and without instrumentation. The decision to place instrumentation should be guided by clinical need at the time of index presentation rather than concerns over reoperation, emphasizing the importance of individualized surgical planning.