Authors: Zalavras, CG, Christensen T, Rigopoulos N, Holtom P, Patzakis MJ
Title: Infection Following Operative Management of Ankle Fractures
Institution: University of Southern California, LAC + USC Medical Center, Los Angeles, CA
Purpose: Infection is a well-known complication of operative management of ankle fractures, however the available information in the literature is limited. Our purpose is to describe the microbiology, management, and outcome of these infections.
Methods: This is a retrospective review of medical records of adult patients treated at our institution from 2000 to 2004 for infections following operative management of ankle fractures. Patients with fractures of the tibial plafond or pathologic fractures were excluded. We identified 26 eligible patients, 20 male and 6 female, with a mean age of 43 years (21-65 years). Twenty-one of 26 patients (81%) were compromised hosts with one or more risk factors, including smoking in 14 patients, low albumin in 14, diabetes mellitus in 5, and intravenous drug abuse in 5. Twenty-two patients (85%) presented with wound drainage and four with soft tissue swelling. The lateral side was involved in 16 patients (62%), the medial in 7 and both sides in 3 patients.Our protocol was the following. Patients presenting up to 10 weeks postoperatively (n=11, mean time from surgery = 4 weeks) were treated by debridement and hardware retention, if implants were stable and the fracture was well-reduced, to be followed by hardware removal after fracture healing (n=6), or they were treated by debridement and hardware removal (n=5) if the implants were loose or the fracture was malreduced. All patients presenting more than 10 weeks postoperatively (n=15, mean time from surgery = 18 months) underwent debridement and hardware removal, with the exception of one patient with diabetes and cirrhosis who underwent a below knee amputation. Two patients (11%) required flap coverage following debridement. Culture-specific antibiotic therapy was administered for 6 weeks. Eight patients did not complete a minimum 6 month follow-up and the outcome is based on eighteen patients with a mean follow-up of 8 months (6-17months).
Results: S. aureus was identified in 17 patients (65%) and was oxacillin-resistant in 6 of these. S.epidermidis was identified in 6 patients (23%), Enterobacter cloacae in 2, Propionibacterium acnes in 2, and Acinetobacter, Serratia, Pseudomonas aeruginosa, vancomycin-resistant Enterococcus, and diphtheroids in one patient each. Six infections (23%) were polymicrobial. The infection recurred in 5 of 18 patients (28%). Four of these five patients were compromised hosts and three recurrences occurred when implants were retained. Three recurrent infections were controlled with repeat debridement and removal of any hardware present. The remaining two patients (one patient with hypothyroidism and low albumin and one patient with diabetes mellitus, peripheral neuropathy and low albumin) finally underwent below knee amputation, resulting in an overall amputation rate of 17% in our series (3 of 18 patients).
Discussion and Conclusion: Infection is a well-known complication of operative management of ankle fractures, occurring in approximately 1-3% of cases and more often in patients with diabetes or other compromising factors. S. aureus and S. epidermidis are the most common pathogens. Management of these infections in compromised patients is challenging with high recurrence and amputation rates.
