Fri., 10/14/11 Knee, Foot & Ankle, Paper #56, 3:30 pm OTA-2011
Definitive Plates Overlapping Provisional External Fixator Pin Sites: Is the Infection Risk Increased?
Chirag M. Shah, MD; Olubusola Brimmo, MD; William M. Ricci, MD;
Michael J. Gardner, MD;
Washington University School of Medicine, St. Louis, Missouri, USA
Purpose: Staged management of high-energy tibial plateau and pilon fractures typically involves acute spanning external fixation followed by later definitive internal fixation. Current practice is to attempt to avoid external fixator pin placement within anticipated surgical incisions to prevent contamination of the surgical field during definitive open reduction and internal fixation (ORIF). However, with the recent popularity of percutaneous plate applications, as well as the biomechanical advantages of long plates for metaphyseal fracture components, this overlap may be unavoidable. The purpose of this study was to compare the infection risk when plates either overlap or do not overlap previous external fixator pin sites in patients with bicondylar tibial plateau fractures and pilon fractures treated with a 2-staged protocol.
Methods: Over a 5-year period from 2005 to 2010, all OTA type 41C bicondylar tibial plateau fractures and all OTA type 43C pilon fractures that were treated via 2-staged external fixation followed by ORIF were reviewed. Patients with follow-up available through fracture healing were included and the incidence of a deep infection that required surgical intervention was recorded. 71 OTA type 41C bicondylar tibial plateau fractures and 67 OTA type 43C pilon fractures were included in the study. The mean duration of follow-up was 8 months. Complete radiographic information was available on all patients. Preoperative and immediate postoperative radiographs were evaluated to determine the positions of definitive plates in relation to external fixator pin sites. In all cases, there was no evidence of active pin-site infection at the time of conversion to definitive ORIF. Patients were grouped into an “overlapping group,” which included those with definitive fixation overlapping or within 5 mm of an external fixator pin site, and a “non-overlapping group.” All patient records were reviewed to determine the incidence of deep infection.
Results: Overall, 19 patients developed a deep wound infection—9 in the pilon group and 10 in the tibial plateau group. For the pilon fractures, 5 of 17 patients (29%) who had overlapping plates and pin sites developed a deep infection, compared to 4 of 50 patients (8%) in the non-overlapping group (P = 0.04). Within the overlapping group of tibial plateau fractures, 8 of 35 patients (23%) had deep infections compared to 2 of 36 (6%) in the non-overlapping group (P = 0.046).
Conclusions: Placement of definitive plate fixation overlapping previous external fixator pin sites significantly increases the risk of deep infection in the 2-staged treatment of bicondylar tibial plateau and pilon fractures. Surgeons must make a conscious effort to place external fixator pins outside of future definitive fixation sites to reduce the overall incidence of deep wound infections. Additionally, consideration must be given to the relative benefit of a spanning external fixator in light of the potential for infection associated with their use.
Alphabetical Disclosure Listing (628K PDF)
• The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an “off label” use). ◆FDA information not available at time of printing. Δ OTA Grant.