Methods: Retrospective cohort analysis.

Objective: Identify demographic and clinical predictors for revision discectomy and compare postoperative complications between primary microdiscectomy (MD) and revision discectomy.

Methods: Patients 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.

Results: Of 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).

Conclusions: Several 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.