Management of late-onset deep surgical site infection after instrumented spinal surgery

There are no universally accepted protocols for the treatment of late-onset deep surgical site infection. This study retrospectively evaluates the methods of aggressive debridement with instrumentation retention, high vacuum closed-suction drain without irrigation, primary wound closure, and antibiotic therapy for the treatment of late-onset deep surgical site infection after instrumented spinal surgery. A total of 4057 patients who underwent instrumented spinal surgeries were surveyed from January 2010 to June 2014. Surgical debridement was performed immediately after late-onset deep surgical site infection was identified. In addition to extended resection of the devitalized and necrotic tissue, the biofilms adhered to the surface of implants were removed meticulously and thoroughly. Primary wound closure was performed on each patient, and closed suction drains were maintained for about 7-10 days without irrigation. Antibiotic therapy was administered for 3 months according to the results of the pathogenic culture. Forty-two patients were identified as having late-onset deep surgical site infection. Staphylococcus aureus was the most common pathogen in this group. Seven patients with late-onset deep surgical site infection had negative bacterial culture results. Infections resolved in all patients. Forty-one patients retained their instrumentation, whereas 1 patient had the implants removed because of Staphylococcus aureus infection, which was found the implants loosening during debridement. Primary wound healing was found in all patients with no recurrence of infection during the follow-up periods. A timely diagnosis, aggressive and meticulous debridement, high vacuum closed-suction drain, routine and adequate use of antibacterial agents are the keys to successfully resolving infection and keeping implants retention in the treatment of late-onset deep surgical site infection after instrumented spinal surgery.