RT Journal
A1 Kessler, Bernhard
A1 Sendi, Parham
A1 Graber, Peter
A1 Knupp, Markus
A1 Zwicky, Lukas
A1 Hintermann, Beat
A1 Zimmerli, Werner
T1 Risk Factors for Periprosthetic Ankle Joint Infection: A Case-Control Study
JF The Journal of Bone & Joint Surgery
JO The Journal of Bone & Joint Surgery
YR 2012
FD October 17
VO 94
IS 20
SP 1871
OP 1876
DO 10.2106/JBJS.K.00593
UL http://dx.doi.org/10.2106/JBJS.K.00593
AB Background: 
  Periprosthetic ankle joint infection is a feared complication of total ankle arthroplasty because the implant fails in the majority of cases. However, risk factors for developing these infections are unknown.Methods: 
  We aimed to determine risk factors for infection in a matched case-control study that included twenty-six patients with periprosthetic ankle joint infection and two control groups, each consisting of fifty-two patients.Results: 
  The prevalence of periprosthetic ankle joint infection within our cohort was 4.7%. Four infections (15%) had a hematogenous origin and twenty-two (85%), an exogenous origin. Staphylococcus aureus was the most common pathogen, followed by coagulase-negative staphylococci. Preoperative predisposing factors associated with infection included prior surgery at the site of infection (odds ratio [OR] = 4.56, 95% confidence interval [CI] = 0.98 to 21.35, and OR = 4.78, 95% CI = 1.53 to 14.91, in comparison with the two control groups) and a low American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score (35.8 versus 49.8 and 47.6 in the two control groups, p ≤ 0.02). The mean duration of the index surgery was significantly longer in the case group than in both control groups (119 versus eighty-four and ninety-three minutes, p ≤ 0.02). After surgery, persistent wound dehiscence (OR = 15.38, 95% CI = 2.91 to 81.34, p = 0.01, in comparison with both control groups) and secondary wound drainage (OR = 7.00, 95% CI = 1.45 to 33.70, and OR = 5.31, 95% CI = 1.01 to 26.78, in comparison with the two control groups, p ≤ 0.04) were associated with the development of a periprosthetic ankle joint infection.Conclusions: 
  Patients at risk for periprosthetic ankle joint infection following total ankle arthroplasty include those with a history of surgery on the ankle, a low preoperative AOFAS hindfoot score, and a long operative time. Postoperatively, patients with a prolonged wound dehiscence or a secondary wound-healing problem are also at risk for infection.Level of Evidence: 
  Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.