Report of a controlled clinical trial comparing automated percutaneous lumbar discectomy and microdiscectomy in the treatment of contained lumbar disc herniation.

Abstract

The results of a randomized controlled trial comparing automated percutaneous lumbar discectomy (APLD) with lumbar microdiscectomy for the treatment of small contained lumbar discal herniations are reported. All patients gave full informed consent and were assessed by an independent observer. Seventy-one patients with radiologically confirmed small contained lumbar disc herniations were randomly assigned to undergo either APLD or lumbar microdiscectomy. All patients were formally assessed by the independent assessor using the Macnab outcome classification at 3 weeks, 2 months, and 6 months after the procedure with follow-up being continued for the duration of the study. The objective was to complete the first randomized and blinded study with sufficient numbers to provide a valid statistical evaluation of these procedures. No previous randomized controlled study comparing these methods has been previously reported. Each procedure was performed by the same surgeon using standard techniques. Statistical analysis was by the chi-square method. In the APLD group only 9 of 31 (29%) had satisfactory outcomes as compared to 32 of 40 (80%) for the microdiscectomy group. Of those patients in the APLD group who had an unsatisfactory outcome and who then opted to undergo surgery (20 of 22 patients), the final success rate was only 65%. Thus, the cumulative success rate of the group initially randomized to APLD including those undergoing either APLD alone or APLD and microdiscectomy after unsuccessful APLD was 22 of 31 (71%). In this group of patients, APLD is seen to be ineffective in the treatment of contained lumbar disc herniation.