A number of classification systems exist for posterior malleolus fractures of the ankle. The reliability of these classification systems remains unclear. The primary aim of this study was to evaluate the reliability of three commonly utilised fracture classification systems of the posterior malleolus. 60 patients across 2 hospitals sustaining an unstable ankle fracture with a posterior malleolus fragment were identified. All patients underwent radiographs and computed tomography of their injured ankle. 9 surgeons including pre-ST3 level, ST3-8 level, and consultant level applied the Haraguchi, Rammelt, and Mason & Molloy classifications to these patients, at two timepoints, at least 4 weeks apart. The order was randomised between assessments. Inter-rater reliability was assessed using Fleiss’ kappa and 95% confidence intervals (CI). Intra-rater reliability was assessed using Cohen's Kappa and standard error (SE). Inter-rater reliability (Fleiss’ Kappa) was calculated for the Haraguchi classification as 0.522 (95% CI 0.490 – 0.553), for the Rammelt classification as 0.626 (95% CI 0.600 – 0.652), and the Mason & Molloy classification as 0.541 (95% CI 0.514 – 0.569). Intra-rater reliability (Cohen's Kappa) was 0.764 (SE 0.034) for the Haraguchi, 0.763 (SE 0.031) for the Rammelt, 0.688 (SE 0.035) for the Mason & Molloy classification. This study reports the inter-rater and intra-rater reliability for three classification systems for posterior malleolus fractures. Based on definitions by Landis & Koch (1977), inter-rater reliability was rated as ‘moderate’ for the Haraguchi and Mason & Molloy classifications; and ‘substantial’ for the Rammelt classification. Similarly, the intra-rater reliability was rated as ‘substantial’ for all three classifications

Management of complex posterior malleolar fractures requires a detailed appreciation of ligamentous and bony anatomy for optimal fracture fixation and restoration of articular congruency. Pre operative planning is vitally important to determine the surgical strategy for complex ankle fractures. We evaluated pre operative planning strategy pre and post implementation of BOAST 12 guidelines (2016) focussing on pre operative CT scans prior to definitive fixation at a major trauma centre. A multi-surgeon retrospective review of prospectively collected data from 2013 to 2018 was performed at a major trauma centre. Patients who had sustained a posterior malleolar fracture and definitive fixation were identified. Information was collated from PICS, PACS, the trauma database and operative notes. 134 patients were identified over a 5 year period who had sustained a posterior malleolar fracture and had definitive fixation. (Pre BOAST guidelines = 61, Post BOAST guidelines = 73). Prior to the implementation of BOAST guidelines ¼ with posterior malleolar fractures did not have a pre operative CT scan (15/61). Post implementation of BOAST 12 90% (66/73)patients with fixation of posterior malleolus fractures had a pre operative CT scan. Posterior malleolus surgery most commonly took place In patients between 18–30 years. Following implantation of BOAST 12 guidelines there was a 15% increase in pre operative CT scanning for ‘complex ankle fractures'. Changes in national guidelines have heavily influenced pre operative planning strategy for ankle fractures at University Hospitals Birmingham. A detailed appreciation of fracture pattern pre operatively helps guide surgical strategy

Summary. Syndesmotic malreduction or failure to restore fibular length are the leading causes for early reoperation after ankle fracture surgery. Anatomic fracture reduction and congruent ankle mortise can be achieved in the majority of cases following revision surgery. Introduction. The goal of ankle fracture surgery is to restore anatomical congruity. However, anatomic reduction is not always achieved, and residual talar displacement and postoperative malreduction predispose a patient to post-traumatic arthritis and poor functional outcomes. The present study aimed to determine the most common surgical errors resulting in early reoperation following ankle fracture surgery. Patients & Methods. We performed a chart review to determine the most common types of malreductions that led to reoperation within the first week following ankle fracture surgery. From 2002 to 2011, we identified 5123 consecutive ankle fracture operations in 5071 patients. 79 patients (1.6%) were reoperated on due to malreduction (residual fracture displacement > 2mm) detected in postoperative radiographs. These patients were compared with an equal number of age- and sex-matched control patients. Surgical errors were classified according to the anatomical site of malreduction: fibula, medial malleolus, posterior malleolus, Chaput-Tillaux fragment, and syndesmosis. Problems related to syndesmotic reduction or fixation were further divided into four categories: malreduction of the fibula in the tibiofibular incisura due to malpositioning of a syndesmotic screw, persistent tibiofibular widening (TFCS > 6 mm), positioning of a syndesmotic screw posterior to the posterior margin of the tibia, and unnecessary use of a syndesmotic screw. Results. The mean patient age was 44 years (18 to 80), and 49% were women. There were no differences between the groups regarding diabetes, tobacco use, peripheral vascular disease, or alcohol abuse. The most common indication for reoperation was syndesmotic malreduction (47 of 79 patients; 59%). Other frequent indications for reoperation were fibular shortening and malreduction of the medial malleolus. We identified four main types of errors related to syndesmotic reduction or fixation, the most common being fibular malreduction in the tibiofibular incisura. The most commonly combined errors were malreductions of the fibula and syndesmosis, which occurred together in 16 of 79 patients (20%). Fracture-dislocation (p = 0.011), fracture type (p = 0.001), posterior malleolar fracture (p = 0.005), associated medial malleolar fracture (p = 0.001), duration of index surgery (p = 0.001), and associated medial malleolar fixation other than with two parallel screws (p = 0.045) were associated with reoperation. Correction of the malreduction was achieved in 84% of reoperated cases. Conclusion. Early reoperation after ankle fracture surgery was most commonly caused by errors related to syndesmotic reduction or failure to restore fibular length. In the majority of cases, postoperative malreduction was successfully corrected in the acute setting

Summary. Quantification of Three-Dimensional Computed Tomography (Q3DCT) is a reliable and reproducible technique to quantify and characterise ankle fractures with a posterior malleolar fragment (. www.traumaplatform.org. ). This technique could be useful to characterise posterior malleolar fragments associated with specific ankle fracture patterns. Introduction. Fixation of posterior malleolar fractures of the ankle is subject of ongoing debate1. Fracture fixation is recommended for fragments involving 25–30% of articular surface1. However, these measurements -and this recommendation- are based on plain lateral radiographs only. A reliable and reproducible method for measurements of fragment size and articular involvement of posterior malleolar fractures has not been described. The aim of this study is to assess the inter-observer reliability of Quantification using Three-Dimensional Computed Tomography (Q3DCT) –modelling. 2,3,4,5. for fragment size and articular involvement of posterior malleolar fractures. We hypothesize that Q3DCT-modelling for posterior malleolar fractures has good to excellent reliability. Patients & Methods. To evaluate inter-observer reliability of Q3DCT-modelling, we included a consecutive series of 43 patients with an ankle fracture involving the posterior malleolus and a complete radiographic documentation (radiographs and computed tomography) Fractures of the tibial plafond (pilon type fractures) were excluded. These 43 patients were divided in 3 different types (Type I, II or III) as described by Haraguchi6. Five patients of each type were randomly selected for an equal distribution of articular fragment sizes. 3D models were reconstructed by 1) creating a mask for every respective slice; 2) select the appropriate dots that separate fracture from tibialshaft; 3) connect masks of each respective slice; and 4) reconstruct a 3D-mesh. After reconstruction of 3D-models, 1) fragment volume; 2) articular surface of the posterior malleolar fragment; 3) articular surface of intact tibia and 4) articular surface of the medial malleolus were calculated by all three observers. A summary of this technique is shown on . www.traumaplatform.org. The inter-observer reliability of these measurements was calculated using the ICC, which can be interpreted as the kappa coefficient. Results. Measurements of the volume of posterior malleolar fracture fragments ranged from 357 to 2904 mm3 with an ICC of 1.00 (Confidence interval (CI) 0.999 – 1.000) Measurements of the articular surface of the posterior malleolar fracture fragment ranged from 25 to 252 mm2 with an ICC of 0.998 (CI 0.996 – 0.999); the articular surface of the intact tibia plafond ranged from 375 to 1124 mm2 (ICC 0.998, CI 0.996 – 0.999); and the articular surface of the medial malleolus ranged from 79 to 149 mm2 (ICC 0.978, CI 0.978 – 0.911). The categorical ratings for all ICC's were defined as almost perfect according to the system of Landis7. Discussion/Conclusion. This study showed that our Q3DCT-modelling technique. 2,3,4,5. is reliable and reproducible to reconstruct ankle fractures, in order to assess fracture characteristics of posterior malleolar fracture fragments. Future research will focus on the association between overall ankle fracture patterns according to Lauge-Hansen, and characterization of posterior malleolar fragment morphology. We hypothesise that supination-exorotation type fractures are associated with smaller (in volume and involved articularsurface) “pull-off” fragments, while pronation-exorotation type ankle fractures are associated with larger (in volume and involved articular surface) “push-off” fragments. The clinical relevance might be that smaller “pull-off” type fractures benefit from positioning screws, while larger “push-off” type fractures require direct open reduction and internal fixation of the posterior malleolar fragment