Radiological risk factors for recurrent lumbar disc herniation after percutaneous transforaminal endoscopic discectomy: a retrospective matched case-control study

Abstract

To investigate radiological risk factors for recurrent lumbar disc herniation (rLDH) after percutaneous transforaminal endoscopic discectomy (PTED). Patients who underwent PTED due to a single-level L4-L5 or L5-S1 disc herniation from January 2013 to May 2019 were enrolled in this study. A matched case-control design was carried out in a single institution. Cases were defined as those who developed rLDH, and controls were matched from those patients without rLDH according to corresponding clinical characteristics. The radiological parameters were compared between two groups. The radiological risk factors for rLDH after PTED were identified by univariate and multivariate logistic regression analysis. A total of 2186 patients who underwent PTED at L4-L5 or L5-S1 level were enrolled in this study. Sixty-eight patients were diagnosed with rLDH, and 136 patients were selected from the remaining 2118 nonrecurrent patients as matched controls. Univariate analysis demonstrated that herniation type (P = 0.009), surgical-level disc degeneration (P < 0.001), adjacent-level disc degeneration (P = 0.017), disc height index (DHI) (P = 0.003), and sagittal range of motion (sROM) (P < 0.001) were significantly related to rLDH. Multiple logistic regression analysis showed that low grade of surgical-level disc degeneration (P < 0.001), senior grade of adjacent-level disc degeneration (P < 0.001), a high DHI (P = 0.012), and a large sROM (P < 0.001) were the radiological independent risk factors. This study showed that low grade of surgical-level disc degeneration, senior grade of adjacent-level disc degeneration, a high DHI, and a large sROM were the radiological independent risk factors for rLDH after PTED.