Pierre-Alban Bouche1, Nicolas Gaujac2, Simon Corsia2, Philippe Leclerc3, Philippe Anract2, Guillaume Auberger3. 1. Orthopaedic Department, Cochin University Hospital, APHP Paris, Paris Descartes University, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France. pierrealban309@gmail.com. 2. Orthopaedic Department, Cochin University Hospital, APHP Paris, Paris Descartes University, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France. 3. Orthopaedic Department, Croix St Simon Hospital, 125 rue d'Avron, 75020, Paris, France.
Abstract
PURPOSE: Undiagnosed and undertreated posterior malleolus fractures lead to early ankle instability and arthritis. A preoperative CT scan could improve the management of those fractures. This study assessed the benefits of a systematic ankle CT scanner to diagnose and manage posterior malleolus fracture. METHODS: A monocentric retrospective cohort study was conducted. Sixty consecutive patients with bimalleolar fractures were operated and underwent a preoperative CT scan. The mean age was 50.0 years old (18.6 years old) with a mean body mass index of 20.3 (kg/m2) (11.4 kg/m2) and 71.7% (43/60) of women. The primary outcome was the rate of posterior malleolus fragment diagnosed on X-rays and on CT scan. Secondly, interobserver and interobserver's agreement were compared between conventional X-rays and CT scan. RESULTS: Thirty-five (58.3%) posterior fragment fractures were observed on X-rays and 53 (88.3%) on the preoperative CT scan (p < 0.01). The intraobserver reproducibility for X-rays was low (0.02 [- 0.23; 0.27]) and moderate for CT scan (0.45 [0.0; 0.84]). The interobserver reproducibility for X-rays was moderate (0.39 [0.15; 0.60]) and excellent for CT scan (0.78 [0.0; 1.0]). CONCLUSION: A wide proportion of bimalleolar fractures are associated with posterior malleolus fractures and undiagnosed with standard X-rays. We advocate a systematic preoperative CT scan in the management of bimalleolar fractures. LEVEL OF EVIDENCE: Level IV, retrospective cohort study. TRIAL REGISTRATION NUMBER: 2218999v0, date of registration: 11/08/2020 (retrospectively registered).
PURPOSE: Undiagnosed and undertreated posterior malleolus fractures lead to early ankle instability and arthritis. A preoperative CT scan could improve the management of those fractures. This study assessed the benefits of a systematic ankle CT scanner to diagnose and manage posterior malleolus fracture. METHODS: A monocentric retrospective cohort study was conducted. Sixty consecutive patients with bimalleolar fractures were operated and underwent a preoperative CT scan. The mean age was 50.0 years old (18.6 years old) with a mean body mass index of 20.3 (kg/m2) (11.4 kg/m2) and 71.7% (43/60) of women. The primary outcome was the rate of posterior malleolus fragment diagnosed on X-rays and on CT scan. Secondly, interobserver and interobserver's agreement were compared between conventional X-rays and CT scan. RESULTS: Thirty-five (58.3%) posterior fragment fractures were observed on X-rays and 53 (88.3%) on the preoperative CT scan (p < 0.01). The intraobserver reproducibility for X-rays was low (0.02 [- 0.23; 0.27]) and moderate for CT scan (0.45 [0.0; 0.84]). The interobserver reproducibility for X-rays was moderate (0.39 [0.15; 0.60]) and excellent for CT scan (0.78 [0.0; 1.0]). CONCLUSION: A wide proportion of bimalleolar fractures are associated with posterior malleolus fractures and undiagnosed with standard X-rays. We advocate a systematic preoperative CT scan in the management of bimalleolar fractures. LEVEL OF EVIDENCE: Level IV, retrospective cohort study. TRIAL REGISTRATION NUMBER: 2218999v0, date of registration: 11/08/2020 (retrospectively registered).