Comparison of Functional and Cosmetic Outcomes According to Fracture Level in Gartland Type III Pediatric Supracondylar Humerus Fractures

BACKGROUND: Supracondylar humerus (SCH) fractures in children have been traditionally categorized according to the Wilkins-modified Gartland classification scheme, which is solely based on the degree of displacement. As this classification does not consider fracture patterns in the coronal or sagittal plane, the relationship between the fracture pattern and prognosis in SCH fractures remains unclear. Therefore, the purpose of this study was to evaluate the relationship between the fracture level and prognosis of pediatric SCH fractures. METHODS: Medical records and radiographs of 786 patients with SCH fractures who underwent surgical treatment between March 2004 and December 2017 were reviewed. A total of 192 patients were included in this study. Anteroposterior elbow radiographs taken at the time of injury were evaluated to obtain the level of fracture. Functional outcomes were evaluated based on modified Flynn grading at the last follow-up. RESULTS: Of 192 patients included in this study, 24 (12.1%), 148 (74.8%), and 20 (10.1%) had fractures in zone 1 (metaphyseal-diaphyseal area), zone 2 (between zones 1 and 3), and zone 3 (metaphyseal-epiphyseal area), respectively. There were significant differences in age at the time of injury (p = 0.011), direction of fracture displacement (p = 0.014), and loss of carrying angle (p < 0.001) between fractures in zone 3 and those in zone 1 or zone 2. Zone 3 fractures and classic zone 2 fractures also showed significant difference in outcomes, with zone 3 fractures having more unsatisfactory outcome than classic zone 2 fractures (p = 0.049). CONCLUSIONS: For SCH fractures, varus deformity of the elbow was more common in zone 3 (metaphyseal-epiphyseal area) than in the other zones. Thus, pediatric orthopedic surgeons should be mindful of the possibility of cubitus varus deformity when treating SCH fractures in zone 3. A thorough postoperative follow-up is required.