Nonoperative treatment of both-bone forearm shaft fractures in children: predictors of early radiographic failure

Abstract

Background: Forearm shaft fractures are the third most common fracture in children. Although closed reduction and casting is the preferred treatment; outcomes remain variable. The purpose of this study was to identify factors associated with failure of nonoperative treatment for pediatric complete forearm shaft fractures and to explore the time frame in which failure is likely.

Methods: Male patients less than 18 years and female patients less than 17 years of age, who were treated for a complete both-bone forearm shaft fracture between January 2005 and January 2008, were included. A pediatric orthopaedic surgeon evaluated all radiographs to confirm the diagnosis. Fractures were classified as proximal, middle, or distal, based one-third division of the shaft. Thresholds for maximum acceptable angulation for male patients < 10 years and female patients < 8 years were as follows: 10 degrees for proximal-third, 15 degrees for middle-third, 20 degrees for distal-third fractures; for female patients ≥ 8 years and male patients ≥ 10 years, up to 10 degrees was considered acceptable at all the levels. Angulation was measured at initial presentation and at weekly intervals for 4 weeks post fracture. Anteroposterior measurements accounted for the natural bow of the radius. Multivariable logistical regression was performed to identify predictors of failure.

Results: Of the 321 patients identified, 282 underwent closed reduction and casting. The average age of patients was 8.5 years, 63% were male. Fifty-one percent of patients exceeded angulation criteria within the follow-up period. Of those who failed, 55% failed by the end of the first week, and 95% failed by 3 weeks. Odds of failure was greatest in patients ≥ 10 years (odds ratio (OR)=2.79; confidence interval (CI) 95, 1.47-5.29), those with proximal radius fractures (OR=6.81; CI95, 3.28-14.14), and those with initial ulna angulations < 15 degrees (OR=2.94; CI95, 1.49-5.83).

Conclusions: Children with 10 years of age or older, with proximal-third radius fractures, and ulna angulation <15 degrees seem to be at highest risk for failure when treated nonoperatively for both-bone forearm fractures. As the majority of failures occur early, early surgical decision-making is encouraged.

Level of evidence: Prognostic Level II.

FIGURE 1

(A) Measurement of fracture level including determination of the distal end of the shaft. (B) Pre-reduction radiograph of a 10 y.o. male with a both-bone forearm fracture. The lateral view shows a proximal level radius fracture with 25° apex volar angulation. (C) Post-reduction radiograph shows the radius with 18° apex volar angulation. (D) At 4 weeks of follow-up, angulation of the radius is 19° apex volar with significant compromise of the interosseous space in the AP view.

FIGURE 2

Histogram illustrating the week during which the first radiographic evidence of failure occurred for the 144 participants who eventually failed at follow-up.