Evaluation of ankle fracture classification systems in 193 trimalleolar ankle fractures

Abstract

Purpose Different classification systems have been developed for ankle fractures. In recent years, the posterior malleolus has gained in importance and led to computed tomography (CT)-based classification systems. The aim of the study was to analyse their reliability, fracture patterns and influence on treatment strategy. Methods Patients with a trimalleolar ankle fracture treated between 2011 and 2020 with preoperative radiographs and CT images were included. The blinded images were independently classified by three reviewers according to the AO/OTA, Herscovici, Bartoníček, Mason and Haraguchi classifications. The interobserver reliability was calculated by Fleiss' kappa (κ). CT images were analysed to determine the dimensions of the posterior malleolus fragments. Patient registries were reviewed regarding the treatment data. Results A total of 193 patients were included. The AO/OTA classification showed almost perfect inter- and intraobserver reliability (Fleiss’ κ = 0.86, 95% CI 0.82–0.90). Regarding the posterior malleolus, the Bartoníček classification demonstrated the highest reliability (Fleiss’ κ = 0.78, 95% CI 0.73–0.83). The Herscovici classification only reached moderate reliability for medial malleolus fractures (Fleiss' κ = 0.59, 95% CI 0.54–0.65). There was a trend towards direct fixation of the posterior malleolus in the last 3 years of the observation period (OR: 2.49, 95% CI 1.03–5.99). Conclusion In trimalleolar ankle fractures, the AO/OTA classification is a reliable system to characterize the type of fracture, but it fails to provide solid information about the posterior malleolus. Nowadays, treatment recommendations for trimalleolar ankle fractures focus on the configuration of the posterior malleolus; therefore, the results of this study advocate the use of the Bartoníček classification as a reliable tool to guide treatment.

Classifications of posterior malleolar fractures: a systematic literature review

“…The studies include a number of 12.614 patients with 12.633 ankle fractures and a weighted median age of 44.55 years (13–100). 5.963 patients were female and 5.231 male, 11 studies did not report gender distribution [ 6 , 20 , 24 , 37 – 44 ]. There were 22 prospective studies, 88 retrospective studies; 11 studies were multicenter, and 99 single center studies (Table 1 ).…”

“…With increasing understanding of fracture morphology and the routine use of computed tomography (CT), efforts have been made in recent years to establish new classification systems based on CT imaging [ 14 , 29 , 30 ]. Until now, there is no international consensus regarding classification and treatment of PMF [ 24 , 31 , 32 ].…”

Beyond the Malleoli: Part 1—Avulsion Fractures of the Tibia and Fibula

“…CT forms the basis for classification and treatment planning of posterior malleolar fractures. 29 The most comprehensive CT-based classification system was proposed by Bartoníček et al 29,30 (Figure 9). Posterior malleolar fragment size, injury severity, and tibiotalar instability progressively increase from types 1 to 4 of this classification system.…”

Beyond the Malleoli: Part 1—Avulsion Fractures of the Tibia and Fibula

“…Posterior malleolar fractures are best appreciated on the lateral view of the ankle series. CT forms the basis for classification and treatment planning of posterior malleolar fractures 29. The most comprehensive CT-based classification system was proposed by Bartoníček et al29,30 (Figure 9).…”

“…CT forms the basis for classification and treatment planning of posterior malleolar fractures 29. The most comprehensive CT-based classification system was proposed by Bartoníček et al29,30 (Figure 9). Posterior malleolar fragment size, injury severity, and tibiotalar instability progressively increase from types 1 to 4 of this classification system 30…”