The effects of maximal radial bowing on forearm rotation in pediatric diaphyseal forearm fractures.

Abstract

To evaluate the effects of radial bowing on forearm rotation in forearm fractures compared with healthy children. A retrospective study was conducted on children aged 1-16years old. Group 1 was children with history of diaphyseal forearm fractures, and group 2 was healthy children. Children in group 1 with ≤ 70° forearm pronation and/or ≤ 80° supination on affected side are defined as "case." In group 2, children with forearm pronation > 70° and/or supination > 80° are defined as "control." Radial bowing was measured on AP radiograph of the forearm; maximal radial bowing (MRB) and location of the maximal radial bowing (LMRB) were recorded. Total of 112 children were included (group 1 = 70, group 2 = 42). In group 1, there were 28 children with ≤ 70° forearm pronation and/or ≤ 80° forearm supination (case group). In group 2, there were 33 children with > 70° forearm pronation and > 80° forearm supination (control group). Mean age of case and control group was 11.08 ± 3.02 and 7.85 ± 3.93years, respectively. Average MRB was 6.15 ± 1.93% and LMRB was 61.94 ± 9.41% in case group. In control group, average MRB was 7.23 ± 1.03% and LMRB was 62.08 ± 4.24%. There was statistically significant correlation between children with ≤ 70° forearm pronation and MRB (P = 0.034) compared with control group. Also, there was statistically significant correlation between children with ≤ 80° forearm supination and MRB (P = 0.023) compared with control group. For ROC curve analysis, MRB ≤ 6.84% showed the association with ≤ 70° forearm pronation (72.2% sensitivity and 73.8% specificity) and MRB ≤ 5.75% associated with ≤ 80° forearm supination (54.6% sensitivity and 84.9% specificity). Children with MRB ≤ 6.84% can result in ≤ 70° forearm pronation, and MRB ≤ 5.75% can be presented with ≤ 80° forearm supination.