Infection rate after minimally invasive noninstrumented spinal surgery based on 4350 procedures.

Methods: Retrospective review of a prospectively collected database. Objective: To assess the rate of postoperative infection associated with minimally invasive noninstrumented spinal surgery.

Background: Infection after spinal surgery results in significant morbidity, extended hospital stay, and significant costs. Minimally invasive spinal techniques require smaller incisions and less dissection, minimizing the risk of postoperative infection.

Methods: Inclusion criteria were patients undergoing posterior spinal surgery using a tubular retractor system with the aid of operative microscope between June 1998 and November 2013. The analysis revealed a total number of 4350 procedures performed in 4037 patients (mean age=53.2 yr). Sixty percent of the patients were male. The majority of procedures were performed in the lumbar spine (98.4%), and the indication was mostly degenerative in nature (96.9%). The databases were then reviewed for any infectious complications.

Results: Postoperative infection was recorded in 4 patients (0.09%). All of them occurred in the lumbar region after discectomy. These patients presented with discitis and underwent revision in the form of open debridement and fusion. The time lapse between the index surgery and revision was 56 days. All 4 patients recovered, with a mean follow-up of 7.5 years.

Conclusions: Infection rate after posterior transtubular microscopic assisted spinal surgery is very low (0.09%). Surgical debridement with fusion was the method of choice in treating such complications. This minimally invasive technique reduces markedly the risk of postoperative infection when compared with other large series published in the literature. Methods: 4.