Predictors for Poor Outcomes After Percutaneous Endoscopic Lumbar Discectomy: A Retrospective Study of 241 Patients

OBJECTIVE: Percutaneous endoscopic lumbar discectomy (PELD) is a popular surgical procedure for the treatment of lumbar disc herniation (LDH). However, a small proportion of patients will have poor surgical outcomes. We sought to identify the predictors for poor outcomes after PELD. METHODS: A total of 241 patients who had undergone PELD were followed up. Their numerical rating scale (NRS) for pain and Oswestry Disability Index scoreswere analyzed. They were divided by outcome (excellent, good, fair, poor) using the MacNab criteria. Their clinical history, physical examination, imaging, and surgical findings were compared among the groups. Ordinal logistic regression analysis was used to identify independent predictors for poor outcomes. RESULTS: The preoperative mean total NRS for back pain, NRS for leg pain, and Oswestry Disability Index scores were 4.3 +/- 2.6, 5.6 +/- 2.5, and 52.1% +/- 23.0%. At 2 years after PELD, the corresponding scores had decreased to 1.2 +/- 1.7, 0.9 +/- 1.5, and 8.4% +/- 11.2% (P < 0.001). The excellent, good, fair, and poor outcome rates were 44.4%, 31.5%, 17.4%, and 6.6%, respectively. Ordinal logistic regression analysis revealed that 2-level PELD (P = 0.001), a history of lumbar fusion (P = 0.007), and Modic changes (P = 0.011) were independent predictors for poor outcomes. Numbness was an independent predictor for excellent outcomes (P = 0.014). CONCLUSIONS: PELD appears to be an effective surgery for LDH. Two-level PELD, a history of lumbar fusion, and Modic changes at the same level were independent predictors for poor outcomes after PELD. Patients with LDH with numbness were more likely to have excellent outcomes.