Preoperative Clinical and Radiographic Risk Factors for Recurrent Lumbar Disc Herniation: Systematic Review and Meta-analysis

OBJECTIVE: Lumbar discectomy is one of the most frequently undertaken procedures for the management of lumbar disc herniation. However, it may be complicated by recurrent disc herniation, with reported rates as high as 25%. To the authors' knowledge, this study is the largest systematic review to date, analyzing the clinical and radiographic risk factors for recurrent disc herniation. METHODS: A systematic literature search of Embase and PubMed/Medline, covering the period from inception to October 1, 2025, was conducted to identify case-control or cohort studies reporting risk factors for recurrent disc herniation. Risk factors were classified into baseline, clinical, and radiographic risk factors. Meta-analysis was performed for any reported risk factor with data from 3 or more studies. The assessment included an evaluation of publication bias and heterogeneity. RESULTS: A total of 51 studies published during the search timeframe, comprising 52,479 patients, met the inclusion criteria. Recurrent disc herniation occurred in 6,794 patients (12.9%). Significant risk factors for disc herniation included high body mass index (BMI) (standard mean difference [SMD], 0.48; 95% confidence interval [CI], 0.26-0.70), diabetes (odds ratio [OR], 1.48; 95% CI, 1.23-1.77), increased sagittal range of motion (SMD, 2.15; 95% CI, 0.35-3.94), and Modic changes (OR, 2.97; 95% CI, 2.20-4.01). No other significant predictors for recurrent disc herniation were identified. CONCLUSION: In conclusion, patients with high BMI, diabetics, increased sagittal range of motion, and presence of Modic changes are at increased risk of recurrent disc herniation. Future prospective studies are needed to validate the risk factors identified in this study associated with recurrent disc herniation.