Primary Closure of External Fixator Pin Sites is Safe After Orthopaedic Trauma Surgery

OBJECTIVES: To determine if rates of pin site infection and surgical site infection amongst patients managed with primary closure after external fixator removal were similar to those allowed to heal secondarily. METHODS: Design: Retrospective cohort Setting: Urban/Suburban Academic Level I Trauma Center Patient Selection Criteria: Patients who had received a lower extremity external fixator for provisional management prior to definitive fixation of lower extremity fractures were included with pin site wounds closed primarily or allowed to heal by secondary intention. Outcome Measures and Comparisons: The rate of pin tract infection and surgical site infection following primary closure of external fixator pin sites relative to patients whose pin sites were allowed to heal via secondary intention. . RESULTS: 256 patients were evaluated, 143 patients (406 pin sites) in the primary closure group and 113 patients (340 in sites) in the secondary closure group. The average age was 49 ± 16 years. Sixty-five percent of included patients were male. There was no difference in pin tract infections between cohorts (Primary=0.5%, Secondary=1.5%, p=0.26). External fixator duration in the primary closure group was 11.5 ± 8.4 days, and 13.0 ± 8.1 days in the secondary closure group (p=0.15). There was a greater rate of surgical site infections in the secondary intention cohort (15.9% vs 7.7%, p=0.047). CONCLUSIONS: There was no difference in pin site infection rate after primary pin site closure relative to patients who were allowed to heal via secondary intention. Furthermore, there was a lower rate of surgical site infection after primary closure. These results challenge the dogma of secondary closure for ex fix pin sites, suggesting that debridement and primary closure is a safe option for management of external fixator pin sites, and may impart benefit in decreasing infection risk. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.