Prediction of Distal Radius Fracture Redisplacement: A Validation Study

• Published in: Journal of orthopaedic trauma Vol. 32; no. 3; p. e92
• Main Authors: Walenkamp, Monique M J, Mulders, Marjolein A M, van Hilst, Jony, Goslings, J Carel, Schep, Niels W L
• Format: Journal Article
• Language: English
• Published: United States 01.03.2018
• Subjects: Aged; Bone Malalignment - diagnostic imaging; Bone Malalignment - etiology; Casts, Surgical; Closed Fracture Reduction - adverse effects; Closed Fracture Reduction - methods; Female; Health Status Indicators; Humans; Male; Middle Aged; Radius Fractures - complications; Radius Fractures - diagnostic imaging; Radius Fractures - surgery; Recurrence; Retrospective Studies; Risk Factors; Wrist Injuries - complications; Wrist Injuries - diagnostic imaging; Wrist Injuries - surgery
• ISSN: 1531-2291
• DOI: 10.1097/BOT.0000000000001105

To externally validate the Edinburgh Wrist Calculator (EWC) in a population of patients with distal radius fractures at risk of loss of threshold alignment. A retrospective cohort study. One academic hospital. All consecutive adult patients with a displaced distal radius fracture with initial dorsal angulation >10 degree and/or an ulnar variance of >3 mm who were treated with closed reduction and cast immobilization between 2009 and 2014. The sensitivity and specificity for diagnosis of loss of threshold alignment within 2 weeks of injury was calculated at the 10%, 40%, and the original 70% probability thresholds. The area under receiver operating characteristic curve was calculated using 2 different thresholds for loss of alignment: Mackenney et al and the Dutch consensus standards. The EWC predicted a greater than 70% chance of redisplacement for only 3 fractures. Redisplacement within 2 weeks occurred in 61 of 99 (62%) fractures according to the thresholds of Mackenney et al and in 18 of 99 (18%) fractures according to the Dutch thresholds. The sensitivity increased and the specificity decreased using a lower probability threshold for redisplacement. The area under the receiver operating characteristic curve of the EWC was poor the Mackenney's thresholds [0.47; 95% confidence interval (CI): 0.36-0.59] and adequate for the Dutch thresholds (0.71; 95% CI: 0.58-0.84). The EWC was a poor predictor of fracture redisplacement greater than threshold in displaced distal radius fractures in our patient population.