Anterior coronoid line as a radiological parameter in evaluating reduction quality of supracondylar humerus fractures: A retrospective analysis

Supracondylar humerus fractures are the second most common pediatric fractures and often require surgical intervention. The anterior coronoid line (ACL), though previously described, has been underutilized and inadequately studied. This study aimed to investigate the diagnostic and post-reduction assessment value of the ACL and to examine its alignment with the AHL as a modified radiological marker. A retrospective analysis was performed on 130 pediatric patients with supracondylar humerus fractures treated between June 2019 and December 2022. Among them, 88 patients underwent surgical treatment and 42 were treated conservatively. The relationship of the ACL to the capitellum and its alignment with the AHL were assessed both before and after reduction. ACL-AHL alignment was categorized as anterior, aligned, or posterior. Of the 88 surgical patients, 40 fractures were severely displaced with no ACL-capitellum contact, all classified as Gartland type III. After reduction, ACL aligned with AHL in 58 patients (69%), was anterior in 21 (25%), and posterior in 7 (6%). The change in ACL-AHL alignment before and after reduction was statistically significant (p < 0.001). No significant association was found between post-reduction ACL alignment and Gartland fracture type (p = 0.197). In 42 conservatively treated type I-IIa fractures, the ACL was consistently aligned with the AHL. The anterior coronoid line can serve as a complementary radiological parameter in evaluating reduction quality in pediatric supracondylar humerus fractures. Its alignment with the anterior humeral line after reduction offers an objective indicator of satisfactory sagittal plane correction. Further prospective studies are warranted to validate its clinical utility.