Extension type II pediatric supracondylar humerus fractures: A radiographic outcomes study of closed reduction and cast immobilization

Background: The treatment of Gartland type II pediatric supracondylar humerus fractures remains controversial. Some argue that closed reduction and cast immobilization is sufficient to treat these fractures, whereas others advocate closed reduction and percutaneous pinning. The purpose of this radiographic outcomes study was to determine whether closed reduction and cast immobilization could successfully obtain and maintain acceptable reduction of extension type II supracondylar humerus fractures. Methods: Prereduction, immediate postreduction, and final radiographs of 155 extension type II fractures that were treated nonoperatively were measured according to the parameters determined earlier to assess the position and alignment of the fracture fragments. These included the anterior humeral line, humerocapitellar angle, Baumann's angle, the Gordon index, and the Griffet index. Results: The average age of the 155 patients at the time of injury was 5.3 years (range: 1 to 13 y). Analysis of the final radiographs, at the final follow-up of 5.3 months, showed that in 80% of patients, the anterior humeral line remained anterior to the mid-third segment of the capitellum (radiographic extension deformity), the mean humerocapitellar angle was 23.77 degrees (range:-11 to 50 degrees), the mean Baumann's angle was 79.40 degrees (range: 62 to 97 degrees), the mean Gordon index was 4.59%, and 44% of patients had a Griffet index between 1 and 3. Conclusions: From this radiographic review, it was observed that not all fractures treated with closed reduction and cast immobilization achieved anatomic position and alignment at final follow-up; however, the long-term clinical and radiographic significance of these findings remains unknown.