SALVAGE OF INSTRUMENTED LUMBAR FUSIONS COMPLICATED BY SURGICAL-WOUND INFECTION

Study Design. This study retrospectively reviewed instrumented lumbar fusions complicated by surgical wound infection and managed by a proto col including antibiotic impregnated beads. Objective. To evaluate the potential for an acceptable clinical outcome in cases of instrumented lumbar fusion complicated by wound infection. Summary of Background D ata. Initial studies of pedicle screw instrumentation suggested an inc reased infection rate versus noninstrumented fusion. The presence of a metallic implant also complicates wound management. Methods. Eight hu ndred fifty-eight instrumented fusions were reviewed with 22 (2.6%) de ep wound infections identified. Analysis included preoperative risk fa ctors, surgical procedure, postoperative course, and clinical outcome. Results. Nineteen patients (mean age, 55 years) were reviewed at a mi nimum of 1 year after surgery. Sixteen (83%) reported significant preo perative health problems. Forty-seven percent of the patients had thre e- and four-level fusions. Mean operative time was 342 minutes. Mean e stimated blood loss was 1620 mL. Infection was diagnosed at an average of 16 days after surgery with wound drainage as the most common prese nting feature. Patients underwent between two and 10 (mean, 4.7) irrig ation procedures. Seven patients had other significant noninfectious c omplications. At follow-up evaluation, no patient had recurrence of in fection. By comparison, to preoperative symptoms, 15 patients were imp roved, three were unchanged, and one deteriorated. Fusion was apparent ly solid in 14 patients, probable in four patients, and nonunion occur red in one patient.Conclusion. Although wound infection is a significa nt complication, this study suggests that aggressive surgical manageme nt can result in preservation of an adequate fusion rate and maintenan ce of an acceptable postoperative outcome.