The necessity of fixation in Gartland type 2 supracondylar fracture of the distal humerus in children (modified Gartland type 2A and 2B).

In type 2 supracondylar fracture, closed pinning has been recommended in most patients. However, a stable, mildly displaced fracture can be treated with nonsurgical means. If stable, mildly displaced fractures are categorized as Gartland type 2A and unstable fractures as type 2B, orthopedic surgeons will be greatly benefited while selecting the most appropriate treatment. This study was conducted to evaluate the results of pinning versus conservative treatment in these two groups of patients. Patients with Gartland type 2 supracondylar fractures were categorized into two groups: the first group (type 2A) consisted of patients with Baumann angle (BA) differing from the uninjured side by less than 5°; the second group (type 2B) consisted of patients with BA difference greater than or equal to 5°. Statistical analysis was performed between the two groups. In type 2A, we also analyzed the data on loss alignment in patients who had undergone closed reduction without fixation to clarify the necessity of fixation. Type 2A fractures had a median BA difference from the uninjured side of 3°, a median lateral capitellohumeral angle (LCHA) difference from the uninjured side of 19.5°, and a shaft condylar angle (SCA) difference from the uninjured side of 18°. Type 2B fractures had a median BA difference of 8°, an LCHA difference of 27°, and an SCA difference of 28°. The BA, LCHA, and SCA differences were statistically significant (P<0.001, P=0.019, and 0.002 between the two types, respectively). Type 2A patients who were treated without fixation had improved SCA of 6° and improved LHCA of 11° from postreduced radiographs, with statistical significance (P=0.018 and P<0.001, respectively). The ROC curve in type 2A patients show that if the LCHA difference or the SCA difference from the uninjured side is less than 18°, it is stable enough to maintain reduction without fixation. Classification into modified type 2A and 2B is very helpful for orthopedic surgeons in determining the most suitable treatment strategy. In type 2A patients with LCHA difference or SCA difference from the uninjured side less than 18°, Kirschner-wire fixation is deemed inessential. In the case of type 2B fractures, fixation was recommended in all patients because of the unstable reduction from loss of BA, LCHA, and SCA.