Clinical outcomes following treatment of deep surgical site infection after fixation of calcaneal fractures: A retrospective case-control study

Deep surgical site infection (SSI) may be a complication of open reduction and internal fixation (ORIF) of calcaneal fractures. This study aimed to describe the characteristics of patients with deep SSI following ORIF of calcaneal fractures via extensile lateral approach (ELA). We compared clinical outcomes of these patients, with a minimum follow-up of one year after successful treatment of deep SSI with a matched control group. In this retrospective case-control study, demographic data, fracture characteristics, bacterial pathogens, medical treatments and surgical approaches were collected, also the outcome was evaluated by the visual analog scale (VAS) for pain, foot function index (FFI) and AOFAS ankle-hindfoot score. The differences in Böhler and Gissane's angles between infected and contralateral feet were measured. By matching a control group of uninfected cases, clinical outcomes were compared between 2 groups using the Mann–Whitney U test. Among 331 calcaneus fractures in 308 patients (mean age, 38.0 ± 13.1; male/female ratio, 5.5), 21 had deep SSI (6.3 %). There were 16 (76.2 %) males and 5 (23.8 %) females with a mean age of 35.1 ± 11.7 years. Thirteen (61.9 %) patients had unilateral fractures. The most common Sanders Type was found to be type II. The most frequent type of detected microorganisms was Staphylococcus species. Intravenous antibiotic therapy, mostly clindamycin, imipenem and vancomycin, based on the microbiological results, was prescribed with a mean±SD duration of 28.1 ± 16.5 days. The mean number of surgical debridements was 1.8 ± 1.3. Implants needed to be removed in 16 (76.2 %) cases. Antibiotic-impregnated bone cement was applied in three (14.3 %) cases. The clinical outcomes of 15 cases (follow up, 35.5 ± 13.8; range, 12.6–64.5 months) were 4.1 ± 2.0, 16.7 ± 12.3 and 77.5 ± 20.8 for VAS for pain, FFI % and AOFAS ankle-hindfoot score, respectively. Comparing with the control group (VAS for pain, 2.3 ± 2.7; FFI %, 12.2 ± 16.6, and AOFAS, 84.6 ± 18.0), only VAS pain was statistically lower in this group (p-value: 0.012). The differences in Böhler and Gissane's angles between both feet of infected cases were − 14.3 ± 17.9 and − 7.7 ± 22.5 (worse in the infected side), respectively. Proper on-time approaches to deep infection following ORIF of calcaneal fractures may lead to acceptable clinical and functional outcomes. Sometimes aggressive approaches with intravenous antibiotic therapy, multiple sessions of surgical debridement, removal of implants and antibiotic impregnated cement are necessary to eradicate deep infection. Level III.