Evaluation of three classification systems for fractures of the distal end of the radius: Frykman, Universal and A.O.

Introduction: Fractures at the distal end of the radius are among the most frequent fractures. Fracture classifications are widely used to define treatment and prognosis. Methods: radiographs were selected from 14 patients with fractures of the distal end of the radius in anteroposterior and profile views, and one case was repeated on purpose. Twelve participants at different stages of professional training (four residents and eight orthopedists) evaluated all the images at two different times, with an interval of 1 week. The inter and intraobserver concordance was analyzed using the weighted Kappa coefficient. The Student's t-test for paired samples was applied to verify if there was a significant difference in the degree of inter-observer concordance between the instruments. Results: Universal classification showed great intra-observer reproducibility (k = 0.72) and moderate interobserver reproducibility (k = 0.48). Frykman had moderate and mild intra and interobserver reproducibility, respectively (k = 0.51 and 0.36). The classification of the group A.O. demonstrated mild intraobserver and interobserver reproducibility (k = 0.38 and 0.25, respectively). Conclusion: The highest intra and interobserver concordance was observed in the Universal classification, followed by Frykman and, finally, that of the group A.O. The reproducibility of the classification did not vary significantly with the degree of experience of the evaluator