Evaluation of Artificial Intelligence (ChatGPT-5.2) in the Classification and Indication for Fixation of Posterior Malleolar Fractures: A Multicenter External Validation Study
Abstract
Introduction: Posterior malleolar fractures have a significant impact on ankle joint congruity. The indication for fixation no longer depends solely on fragment size but also on fracture morphology. Artificial intelligence (AI) has emerged as a tool to support clinical decision-making. The objective of this study was to evaluate the ability of AI to classify posterior malleolar fractures and determine the indication for fixation, compared with a reference standard based on expert consensus. Materials and Methods: A retrospective diagnostic accuracy study with external validation was conducted in accordance with the STARD-AI and GAMER guidelines. A protocol based on the Bartoníček and Rammelt classification was developed using 24 cases for calibration. Subsequently, 9 cases were evaluated using radiographs and computed tomography scans and analyzed by 12 experts and the ChatGPT-5.2 model. Agreement in fracture classification and sensitivity for the indication for fixation were assessed using Cohen’s kappa coefficient. Results: ChatGPT-5.2 achieved 78% agreement in fracture classification, with a kappa coefficient of 0.56, indicating moderate agreement. Sensitivity for the indication for posterior malleolar fixation was 100%. Conclusions: Artificial intelligence demonstrated performance comparable to that of experts in the classification of posterior malleolar fractures and high sensitivity in determining the indication for fixation. It proved useful as a supportive tool in medical education settings. Studies with larger sample sizes are needed to validate these findings.Downloads
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