A study that sought to evaluate the safety of preparing the external fixator in situ during staged fixation of pilon fractures found that overall patients had relatively high infection (23.3 percent) and unplanned reoperation (11.3 percent) rates. However, prepping elements of the external fixator into the surgical field did not lead to an increase in rates of infection or reoperation.

Elaborating on the aims of the poster study, which was displayed during the AAOS 2023 Annual Meeting, presenting author Teja Yeramosu explained that the study approach was to compare the risk of fracture-related infection (FRI) and unplanned reoperation after staged open reduction and internal fixation (ORIF) of pilon fractures between cases in which components of the temporizing external fixator (ex-fix) were prepped into the surgical field and cases in which it was completely removed prior to definitive fixation.

“To the best of our knowledge, there has been no comparative clinical study evaluating the safety of leaving the ex-fix in situ during staged ORIF of pilon fractures,” Mr. Yeramosu, medical student at Virginia Commonwealth University, told AAOS Now.

The investigation was a multi-surgeon, retrospective, comparative cohort study on patients aged >18 years with pilon fractures who underwent operative treatment over a 10-year period between Jan. 1, 2010, and Jan. 1, 2020, at an academic level 1 trauma center. Medical records and radiographic images were reviewed for each patient to assess demographics, clinical characteristics, and surgical outcomes. The primary outcome measures were FRI and unplanned reoperation.

The study group consisted of 133 patients who were treated with staged ORIF, including 47 fractures that had components of the original ex-fix prepped in situ during surgery for ORIF (Fig. 1) and 86 that had the ex-fix entirely removed prior to prepping and draping. The overall rate of FRI was 23.3 percent, whereas the overall rate of unplanned reoperation was 11.3 percent, with a 4.5 percent rate of arthrodesis and 6.8 percent rate of amputation. There was no difference in FRI between the group in which ex-fix was prepped in and the group in which it was completely removed (23.4 percent versus 23.3 percent, P = 0.985) and no difference in the overall rate of unplanned reoperation (10.6 percent versus 11.6 percent, P = 0.863).

Patients who developed an FRI were managed in the initial temporizing ex-fix for a longer time before definitive fixation (21.68 ± 11.44 days versus 16.14 ± 10.12 days, P = 0.018). Looking at the subset of patients with FRI, those with the ex-fix prepped in situ had a higher prevalence of infection with methicillin-resistant Staphylococcus aureus and methicillin-sensitive S. aureus (81.8 percent versus 40 percent, P = 0.021).

Summarizing the clinical takeaways of the study, Mr. Yeramosu commented: “Prepping elements of the external fixator in situ for patients with pilon fracture undergoing definitive ORIF does not lead to an increase in rates of FRI or unplanned reoperation. As such, this study offers clinical support for a common practice used to assist in the operative management of pilon fractures.”

He added, “Future studies are needed to study and define a protocol for the appropriate management of the external fixator prior to definitive fixation, especially with regard to prolonged utilization.”

In regard to limitations of the study, Mr. Yeramosu said they include its retrospective nature and the small sample sizes utilized in the sub-analyses. “This is a single-institution study, as well as a multi-surgeon (10 surgeons) study with variability in specific treatment protocols for prepping the ex-fix components within the surgical field,” he added. “However, these differences in treatment protocols may improve the generalizability of the study, as it may also be representative of the varying surgical prep and protocols used in the community.”

In conclusion, the authors commented, “Although there were relatively high complication rates in this cohort of pilon fractures treated with staged ORIF, prepping in components of the external fixator did not lead to a significant increase in rates of FRI nor unplanned reoperation. This study offers clinical guidance regarding maintaining and prepping in situ the existing external fixator during definitive fixation of pilon fractures.” 

Mr. Yeramosu’s coauthors of “Safety of Prepping the External Fixator In Situ during Staged Fixation of Pilon Fractures: A Retrospective Comparative Cohort Study” are Porter Young, MD; David Cinats, MD; Clarence Toney, MD; Jibanananda Satpathy, MD; Tejas Tushar Patel, MD; Stephen L. Kates, MD; and Paul William Perdue, MD.

Visit aaos.org/ameducation to view an eposter of this study or any AAOS 2023 Annual Meeting poster.

Terry Stanton is the senior medical writer for AAOS Now.