Predictors and Postoperative Complication Risks for Revision Discectomies Following Primary Lumbar Microdiscectomy.

Study DesignRetrospective cohort analysis.ObjectiveIdentify demographic and clinical predictors for revision discectomy and compare postoperative complications between primary microdiscectomy (MD) and revision discectomy.MethodsPatients who underwent one-level primary lumbar MD and subsequent one-level revision discectomy for lumbar disc herniation were identified using the PearlDiver national database. Multivariate regression analysis was performed to identify predictors of revision discectomy, assess 30-day postoperative complications and opioid use, and assess the likelihood of future lumbar fusion.ResultsOf 52,310 patients undergoing primary lumbar MD, 4536 (7.98%) required revision. Independent predictors included smoking (aOR: 1.72), obesity (aOR: 1.44), lateral disc herniation (aOR: 1.69), coagulopathies (aOR: 1.34), CAD (aOR: 1.62), anemia (aOR: 1.38), diabetes (aOR: 1.47), hypertension (aOR: 1.63), peripheral vascular disease (aOR:1.33), preoperative opioid use (aOR: 2.06), postoperative opioid use (aOR: 1.80), and depression (aOR: 1.73) (all, P < 0.01). Revision discectomy was associated with higher risks of infection (aOR: 1.78), AKI (aOR: 1.41), VTE (aOR: 1.46), dehiscence (aOR: 2.32), neurological injury (aOR: 1.48), durotomy (aOR: 2.19), epidural hematoma (aOR: 2.61), I&D (aOR: 2.32), opioid use (aOR: 1.73), and increased fusion rates (all P < 0.05).ConclusionSeveral patient-related factors increase the risk of revision MD, which is associated with additional short- and long-term complication risks relative to the index procedure. These findings inform expectations for disease progression and postoperative outcomes in revision MD. Revision discectomy should be avoided when possible.