Clinical efficacy of three different minimally invasive procedures for far lateral lumbar disc herniation.

Far lateral lumbar disc herniation (FLLDH) accounts for 2.6% to 11.7% of all lumbar herniated discs. Numerous surgical approaches have been described for treating this condition. The purpose of this study was to evaluate minimally invasive surgical techniques for the treatment of FLLDH.From June 2000 to March 2006, 52 patients with FLLDH were treated with minimally invasive procedures. All patients were assessed by anteroposterior and lateral roentgenography and computed tomography (CT). Some patients underwent myelography, discography, and magnetic resonance imaging. Procedures performed included Yeung Endoscopy Spine System (YESS) (n = 25), METRx MicroDiscectomy System (n = 13), and X-tube (n = 14). Patients were followed up for a mean of 13.5 months. Clinical outcomes were assessed using a visual analog scale (VAS) and Nakai criteria.All 3 procedures significantly improved radiating leg symptoms (P < 0.005). After surgery, 84.0%, 84.6%, and 92.8% of patients in the YESS, METRx, and X-tube groups had excellent or good outcomes. There were no statistically significant differences of VAS scores between the groups. The YESS procedure was associated with the shortest operation time, simplest anesthesia, and least trauma compared with the other 2 procedures, especially for type I herniations. The METRx procedure was the most suitable for type II herniations and posterior endoscopic facetectomy. Posterior lumbar interbody fusion and unilateral pedicle screw instrumentation with X-tube was the most suitable for herniations combined with degenerative lumbar instability (type III).Minimally invasive strategies and options should be determined with reference to the type of FLLDH.