Permanent implantation of antibiotic cement over exposed instrumentation eradicates deep spinal infection

In this case series, we describe an infection treatment protocol involving permanent implantation of antibiotic cement that is effective in eradicating deep infection. Surgical site infection (SSI) is a devastating complication of spine surgery. Unlike the gold-standard two-stage revision in North American hip and knee arthroplasty, there exists no standardized, accepted protocol for the management of deep SSI with instrumentation. Because removal of hardware in an unstable, instrumented spine can result in serious neurologic sequelae, retention of instrumentation with elimination of bacterial colonization on implants is the goal. Using Current Procedural Terminology (CPT) codes, institutional medical records were queried to identify all posterior spinal procedures performed by the senior surgeon from 2008 through 2014. Thirty-four patients were identified as having an implant-associated SSI. Exclusion criteria included: (I) superficial SSI, and (II) those with less than 36 months of follow-up. The study population consisted of ten patients with deep implant-associated SSI who underwent our novel protocol of operative debridement and permanent coating of exposed implants with high-dose antibiotic cement. Postoperative infection presented after an average of 41.4±57.5 days (range, 6.0–207.0 days) from the index procedure. The mean follow-up was 64.4±18.1 months (range, 44.0–98.0 months). At final follow-up, none of the ten patients (0%) in our series had evidence of continued deep infection and none required removal of hardware. Ten of the ten patients (100%) were able to clear infection with a single stage debridement and coating with antibiotic cement. Only 1 of the 10 patients (10%) developed a pseudarthrosis. In conclusion, permanent implantation of antibiotic cement over exposed instrumentation is effective in preserving spinal instrumentation during infection eradication, preventing infection recurrence, and minimizing operative debridements.