Open versus minimally invasive lumbar microdiscectomy: comparison of operative times, length of hospital stay, narcotic use and complications.

To determine if a minimally invasive approach to lumbar microdiscectomy reduces post-operative pain, length of hospital stay, or frequency of complications we retrospectively compared medical records of single level microdiscectomy patients by a single surgeon performed using a traditional open approach versus a minimally invasive approach. Thirty-five patients were in the open group: 63% male, average age 41.2 years, and 31 patients were in the minimally invasive group: 68% male, average age 42.1 years. There was no difference in surgical time or blood loss between the open and minimally invasive groups: 84.1 versus 76.8 minutes and 51.4 versus 69.7 mL, respectively. There were no significant complications intraoperatively or within the 30 day post-op period for either group. The average dose of intravenous morphine taken was 12.9 mg for the minimally invasive group and 15.7 mg for the open group (P=0.04). The average dose of hydrocodone was 13.4 mg for the minimally invasive group and 20.9 mg for the open group (P=0.03). The open group took an average of 11.7 mg oxycodone, the minimally invasive none. 45.2% of patients in the minimally invasive group were discharged on the same day as surgery compared to 5.75% in the open group (P=0.001). Microdiscectomy was performed safely and effectively through a minimally invasive expanding retractor system and operating microscope. Surgical times, blood loss, complications, and outcome were similar to a traditional open microdiscectomy while pain medication requirements and hospitalization were significantly less.