Risk Factors for Deep Surgical Site Infection Following Operative Treatment of Ankle Fractures

SLR - April 2013 - Marc Spiegel

Reference: Mikko T. Ovaska, MD, Tatu J. M¨akinen, MD, PhD, Rami Madanat, MD, PhD, Kaisa Huotari, MD, PhD,
Tero Vahlberg, MSc, Eero Hirvensalo, MD, PhD, and Jan Lindahl, MD. Risk Factors for Deep Surgical Site Infection Following Operative Treatment of Ankle Fractures. J Bone Joint Surg Am. 2013;95:348-53

Scientific Literature Review

Reviewed by: Marc Spiegel, DPM

Residency Program: Beth Israel Deaconess Medical Center, MA

Podiatric Relevance:
Surgical site infections are associated with substantial morbidity, as well as an increase in utilization of hospital resources. It is of the upmost importance that physicians minimize these complications to the best of our abilities. While an absolute zero surgical site infection rate is ideal, it is not feasible. However, by controlling several modifiable risk factors, it is shown that we can statistically reduce the incidence of surgical site infections. It is therefore in our best interest to understand these risk factors and take all precautions necessary to prevent, rather than fix, the complication of surgical site infection. As we often tell our diabetic patients, prevention trumps treatment. This article focuses on the risk factors of surgical site infections following ORIF of ankle fractures.

Methods:
An age- and sex-matched case-control study was performed to identify patient and surgery-related risk factors for deep surgical site infection following operative ankle fracture treatment. The study was performed at a level I trauma center. One thousand, nine hundred and twenty-three ankle fracture operations performed in 1,915 patients from 2006 through 2009 were reviewed, all of which were treated with ORIF. Out of those, a total of 131 patients suffered deep infections, which were characterized by all three of the following: clinical signs of infection, positive bacterial cultures of specimen, and osteosynthesis material visible or palpable within the wound. These infected patients were identified and compared with an equal number of uninfected control patients matching for key demographics. Risk factors for infection were determined with use of conditional logistic regression analysis.

Risk factors were identified by a review of medical, operative, microbiological, and radiological records. Information gathered from this medical review included demographic data, comorbidities of the patients, injury and mechanism, delay from fracture to admission, condition of the soft tissues, presence of a fracture-dislocation, fracture type, use of a temporary external fixator, duration of surgery, use of a tourniquet, surgeon experience, possible difficulties encountered during the surgery, suboptimal timing of antibiotic prophylaxis, wound closure method, application of a cast in the operating room, postoperative noncompliance and wound complications.

Multiple statistical tests were then used to compare the case and control groups and identify independent risk factors for deep surgical site infection

Results:
The incidence of deep surgical site infection was 6.8 percent. Univariate analysis showed diabetes, alcohol abuse, fracture-dislocation and soft-tissue injury to be significant patient-related risk factors for infection. Surgery-related risk factors were suboptimal timing of prophylactic antibiotics, difficulties encountered during surgery, and wound and fracture malreduction. Independent risk factors for infection identified by multivariable analyses were tobacco use and duration of surgery of more than 90 minutes. Cast application in the operating room was independently associated with a decreased infection rate.

Conclusions:
The results demonstrate that there are several modifiable risk factors when dealing with ORIF of the ankle. While the article focuses on injuries of the ankle, these risk factors may be applicable to patients undergoing any lower extremity operation. While trauma patients may often need immediate surgery, recognition of many of these risk factors including, smoking, alcohol abuse, and compromised soft tissue may impact your pre-op planning and possibly even your patient’s surgical candidacy.