ARTHROSCOPIC ASSESSMENT OF DISTAL TIBIOFIBULAR SYNDESMOSIS IN ANKLE FRACTURES: PREVALENCE BY WEBER TYPE

Abstract

Introduction: Ankle fractures are common injuries, but the true extent of damage to the distal tibiofibular syndesmosis is often underestimated when only radiographs and standard stress tests are used. Arthroscopy offers a direct and dynamic view of the syndesmosis and may uncover instability that would otherwise be missed in different Danis–Weber fracture types.

Material and methods: This retrospective-prospective, single-center study included 64 adults with unstable ankle fractures treated with routine ankle arthroscopy, followed by open reduction and internal fixation. Fractures were classified as Weber A, B, or C. During arthroscopy, the distal tibiofibular syndesmosis was probed under lateral stress and categorised as stable or unstable. The prevalence of arthroscopically confirmed syndesmotic instability was calculated for the whole cohort and for each Weber type, and the association between Weber type and instability was tested with the chi-square test.

Results: Our patient cohort consisted of 16 Weber A, 29 Weber B, and 19 Weber C fractures. Syndesmotic instability confirmed arthroscopically was found in 23 of 64 patients (35.9%). Instability was present in 1/16 Weber A (6.3%), 9/29 Weber B (31.0%), and 13/19 Weber C fractures (68.4%). The prevalence of instability increased from Weber A to Weber C, and the association between fracture type and arthroscopic instability was statistically significant (χ², p < 0.001).

Conclusions: In this series of unstable ankle fractures, roughly one in three patients had an unstable distal tibiofibular syndesmosis during arthroscopic testing, with the highest rates in Weber C and intermediate in Weber B fractures. Although uncommon, instability was also seen in one Weber A fracture, showing that fibular fracture level alone does not fully exclude syndesmotic involvement. Surgeons should consider selective or routine arthroscopic evaluation of the syndesmosis, especially in Weber B and C injuries.