Peroneal Tendon Dislocation after Talus Fracture

Category: Trauma; Ankle Introduction/Purpose: Traumatic peroneal tendon dislocation (PTD) have been described in association with fractures of the pilon and calcaneus, however, the incidence of PTD after fractures of the talus has not been previously reported in the U.S. Methods: This was a retrospective review of adult patients with operatively treated fractures of the talus treated at a level I academic trauma center between 2007 and 2021. Charts, radiographs, and advanced imaging, when available, were reviewed for patient demographics, injury characteristics, and complications including diagnosis of peroneal tendon dislocation. Results: 126 patients with 128 talus fractures were included. Incidence of peroneal tendon dislocation was 21.1% (n=27). Peroneal rupture was found separately in 3 instances (2.3%). Among 27 cases of PTD, 14 (51.9%) were diagnosed based on advanced imaging, 7 (25.9%) by review of the operative report, and 6 (22.2%) based on both. 89.3% (n=25) of PTDs were diagnosed at time of injury, whereas 7.4% (n=2) were diagnosed several months after. Three PTDs underwent delayed surgical intervention due to delayed diagnosis (n=1), or missed dislocation by the surgeon, although evident on injury scans (n=2). Lateral process fractures had increased odds of PTD (OR 3.4, 95% CI: 1.3-8.9, p=0.012), as well as fractures with a positive fleck sign on radiographs (OR 14.3, 95% CI: 4.0-50.7, p=0.0001). Conclusion: Peroneal tendon dislocation with fracture of the talus is relatively common and was identified in one out of five fractures within the studied cohort. Surgeons and radiologists should be cognizant of this injury, especially in the setting of a lateral process fracture and a positive fleck sign.