INTRODUCTION: Conventional microdiscectomy is the most frequently performed surgery for patients with lumbar disc herniation. Transmuscular tubular discectomy has been introduced to increase the rate of recovery, although evidence is lacking. We evaluated the outcome of tubular discectomy compared with conventional microdiscectomy in a double-blinded randomised controlled multicenter trial.

METHODS: 328 patients with persistent leg pain (> 8 weeks) due to lumbar disc herniation were randomly assigned to undergo tubular discectomy (167 patients) and conventional microdiscectomy (161 patients). Patients and researchers were kept blinded of the allocated treatment during the follow-up period of 2 years. The main outcome measures were scores from the Roland-Morris Disability Questionnaire for Sciatica (RDQ), visual analogue scale (VAS) for leg pain and back pain, and Likert self rating scale of global perceived recovery. Repeated measurements analyses according to the intention-to-treat principle were used.

RESULTS: During follow-up, there were no significant differences between tubular discectomy and conventional microdiscectomy in RDQ scores (between-group mean difference, 0.6; 95% CI, -0.3 to 1.6). Patients treated with tubular discectomy reported more leg pain (between-group mean difference of VAS leg pain, 3.3 mm; 95% CI, 0.2 to 6.3 mm) and more back pain (between-group mean difference of VAS back pain, 3.0 mm; 95% CI, -0.2 to 6.3 mm) as those patients treated with conventional microdiscectomy. At 2 years, 71% of the patients assigned to tubular discectomy documented good recovery versus 77% of the patients assigned to conventional microdiscectomy (odds ratio 0.76; 95% CI, 0.45 to 1.28; P=0.35). The rate of repeated surgery within 2 years after tubular discectomy and conventional microdiscectomy was 15% and 10%, respectively (P=0.22).

DISCUSSION: Tubular discectomy and conventional microdiscectomy resulted in similar functional and clinical outcome, although tubular discectomy resulted in less favorable results for leg pain, back pain, and perceived recovery.