Is Definitive Plate Fixation Overlap with External Fixator Pin Sites A Risk Factor for Infection in Pilon Fractures?

SLR - April 2021 - Matthew J. Dougherty

Reference: Dombrowsky A, Abyar E, McGwin G, Johnson M. Is Definitive Plate Fixation Overlap with External Fixator Pin Sites A Risk Factor for Infection in Pilon Fractures? J Orthop Trauma. 2021 Jan; 35(1) 7-12.  

Level of Evidence: Level III

Scientific Literature Review 

Reviewed By: Matthew J. Dougherty, DPM
Residency Program: Temple University Hospital – Philadelphia, PA 

Podiatric Relevance: Pilon fractures are complicated high-energy injuries that can include both massive soft tissue and osseous trauma. These injuries often require stabilization initially via external fixation followed by staged internal fixation once the soft tissue injury has stabilized. Historically, surgeons have advocated placing external fixation pins away from areas where definitive fixation will eventually be placed to reduce complications with the definitive fixation. Unfortunately, this may compromise the appropriateness of the external fixation. The aim of this study was to determine any increased risk of deep postoperative infection in placing definitive fixation in an area where previous external fixator pins were located.  

Methods: This is a retrospective cohort study completed at a Level 1 trauma center between the years of 2012-2018. Patients were included if they were older than 15 years, underwent treatment for any subtype of type 43 OTA/AO fracture classification with a staged protocol and greater than three months of follow-up. Staged treatment was defined as temporizing external fixation followed by delayed ORIF. In total, 146 patients met inclusion criteria and were treated by one of four fellowship-trained orthopedic surgeons. The primary outcome measure was the development of a deep postoperative infection relative to fixation placement. 

Results: Of the 146 ankles, 22 ankles (15 percent) developed deep postoperative wound infections. Seven of those 22 ankles had overlap of definitive fixation and external fixation compared to 15 that did not have overlap of definitive fixation and external fixation. In addition, of the 22 ankles with deep wound infections, 11 (50 percent) were open fractures. There was no significant difference in percentage of postoperative wound infections in regards to amount of overlap of internal fixation and external fixation or distance from plate to pin site.

Conclusions: The authors concluded there is no increased risk of deep wound infection with overlap of definitive internal fixation at or near sites of prior external fixation. Based on the authors’ recommendations, foot and ankle surgeons should prioritize pilon fracture treatment with temporary external fixator placement, regardless of where future definitive internal fixation is planned, to achieve optimum stability.