Tubular diskectomy vs conventional microdiskectomy for sciatica: a randomized controlled trial

Abstract

Context: Conventional microdiskectomy is the most frequently performed surgery for patients with sciatica due to lumbar disk herniation. Transmuscular tubular diskectomy has been introduced to increase the rate of recovery, although evidence is lacking of its efficacy.

Objective: To determine outcomes and time to recovery in patients treated with tubular diskectomy compared with conventional microdiskectomy.

Design, setting, and patients: The Sciatica Micro-Endoscopic Diskectomy randomized controlled trial was conducted among 328 patients aged 18 to 70 years who had persistent leg pain (>8 weeks) due to lumbar disk herniations at 7 general hospitals in The Netherlands from January 2005 to October 2006. Patients and observers were blinded during the follow-up, which ended 1 year after final enrollment.

Interventions: Tubular diskectomy (n = 167) vs conventional microdiskectomy (n = 161).

Main outcome measures: The primary outcome was functional assessment on the Roland-Morris Disability Questionnaire (RDQ) for sciatica (score range: 0-23, with higher scores indicating worse functional status) at 8 weeks and 1 year after randomization. Secondary outcomes were scores on the visual analog scale for leg pain and back pain (score range: 0-100 mm) and patient's self-report of recovery (measured on a Likert 7-point scale).

Results: Based on intention-to-treat analysis, the mean RDQ score during the first year after surgery was 6.2 (95% confidence interval [CI], 5.6 to 6.8) for tubular diskectomy and 5.4 (95% CI, 4.6 to 6.2) for conventional microdiskectomy (between-group mean difference, 0.8; 95% CI, -0.2 to 1.7). At 8 weeks after surgery, the RDQ mean (SE) score was 5.8 (0.4) for tubular diskectomy and 4.9 (0.5) for conventional microdiskectomy (between-group mean difference, 0.8; 95% CI, -0.4 to 2.1). At 1 year, the RDQ mean (SE) score was 4.7 (0.5) for tubular diskectomy and 3.4 (0.5) for conventional microdiskectomy (between-group mean difference, 1.3; 95% CI, 0.03 to 2.6) in favor of conventional microdiskectomy. On the visual analog scale, the 1-year between-group mean difference in improvement was 4.2 mm (95% CI, 0.9 to 7.5 mm) for leg pain and 3.5 mm (95% CI, 0.1 to 6.9 mm) for back pain in favor of conventional microdiskectomy. At 1 year, 107 of 156 patients (69%) assigned to tubular diskectomy reported a good recovery vs 120 of 151 patients (79%) assigned to conventional microdiskectomy (odds ratio, 0.59 [95% CI, 0.35 to 0.99]; P = .05).

Conclusions: Use of tubular diskectomy compared with conventional microdiskectomy did not result in a statistically significant improvement in the Roland-Morris Disability Questionnaire score. Tubular diskectomy resulted in less favorable results for patient self-reported leg pain, back pain, and recovery.

Trial registration: isrctn.org Identifier: ISRCTN51857546.