Influential factors for recurrent lumbar disc herniation after microendoscopic discectomy

English Keywords:Lumbar disc herniation  Microendoscopic discectomy  Recurrence  Risk factors

English Abstract:

  【Abstract】 Objectives: To investigate the recurrence rate after microendoscopic discectomy(MED) for lumbar disc heniation(LDH) retrospectively, and to explore the influential factors related to recurrence. Methods: From January 2009 to January 2014, 322 patients with single-level LDH who underwent MED were enrolled in this study. There were 203 males and 119 females（age range, 14-84 years; mean age, 39±12 years; follow-up range, 12-68 months; mean follow-up, 28.6±17.8 months). The clinical curative effect was evaluated by using lumbar JOA score system. The influential factors were investigated including age, gender, occupation, body-mass index(BMI), postoperative activity level, and level, type, site of LDH. The relationships between the variables and recurrent LDH were evaluated by single factor chi-squared and multiple logistic regression analysis. Results: Recurrent LDH was observed in 21 patients(6.5%). There were 19 cases at the same level in the ipsilateral side as the original LDH, and 2 cases in the contralateral side. The mean time interval between MED and recurrence was 13.6±17.8 months(range, 1-60 months). There were 16(76.2%) recurrent patients within 1 year after MED. Single factor chi-squared analysis revealed herniation type and postoperative activity level significantly related with recurrent LDH, which had no significant correlation with other factors including age, gender, occupation, body-mass index(BMI), level and site of LDH. Multivariate analysis showed that herniation type and postoperative activity level were risk factors for recurrent LDH(P=0.009, OR=2.762, CI=1.282-5.942; P=0.026, OR=1.907, CI=1.079-3.370, respectively). Conclusions: Our study suggests that extrusion, sequestration and high-intensity of postoperative activity level may significantly increase the incidence of recurrent LDH.