gms | German Medical Science

Objectives: Decision making in treatment of forearm fractures is mainly based on radiographic parameters. However, evidence for conservative or operative treatment is still lacking. Aim of this study is to evaluate radiographic parameters predicting a good outcome and to define inter-observer reliability of these parameters.

Methods: In a retrospective case-control study, we evaluated 75 patients with a conservatively treated forearm fracture. Two senior orthopedic surgeons evaluated initial digital radiographs in two planes (T0) and recommended either conservative or operative treatment according to the defined criteria. Translation of the radius and ulna of less than 50% of the bone diameter as well as a cast index (the ratio of sagittal to coronal diameter from the inside edges of the cast at fracture site) of less than 0.84 indicated conservative treatment. If these values were extended, an operative treatment was recommended retrospectively. Nevertheless all patients had been treated conservatively. Therefore in a second step both observers evaluated images, recorded one year post trauma and ROM of pronation and supination detected a T1. The Parameters for an unsatisfactory radiological outcome were radial shortening and radiographic angulation of the forearm of more than 10°-15° according to the different age. The chi-square test was used to compare the indication rates. The level of significance was defined at p < 0.05 for all tests.

Results and Conclusion: Radiologic data of 75 patients with a mean age of 8.4±3.5 years (2-15y) were available for analysis. 26/75 (34.7%) conservatively treated patients had an unsatisfactory radiological outcome at T1 regarding radial shortening and angulation of the forearm. Observer 1 predicted 39/45 good results for conservative treatment whereas 20/30 patients (66.6%) with a retrospective recommendation for surgery developed a poor radiologic outcome (chi-square=22.6; p<0.0001). Observer 2 predicted 41/48 (85.4%) of good results after conservative treatment and recommended operative treatment in 27 patients whereof 19 (70.4%) occurred to have a poor radiologic outcome (chi-square=23.7; p<0.0001). The analysis showed that only the cast index was a resilient predictor for poor outcomes. The translation of the radius or ulna was not a risk factor for a consecutive angulation or radial shortening. As far as the functional evaluations is concerned, 16/26 (61.5%) patients had some loss of 5° pronation compared to unaffected forearm and 14/26 (53.84%) had some loss of 5° supination compared to unaffected forearm. In summary a cast index less than 0.84 is a viable predictor for a good radiological outcome after conservative treatment in pediatric forearm fractures also providing a good inter-observer reliability. As far as clinical evaluation we found a strong relationship between unsatisfactory radiological results and functional outcome