Three-dimensional deformity analysis of malunited distal radius fractures and their influence on wrist and forearm motion.

Little information exists about three-dimensional (3-D) deformity patterns of malunited distal radius fractures including axial deformity. The current study aimed to clarify the 3-D deformity pattern of malunited distal radius fractures and reveal the influence of osseous deformities, including axial rotation deformity, on wrist and forearm motion. The deformity of 20 dorsally tilted malunions were evaluated using 3-D computer models created from CT data, and correlations between deformity components and range of motion were assessed. The 3-D deformity analysis showed that axial malalignment in pronation, which showed a correlation with the degree of radial tilt deformity, was very common. A radial tilt deformity of > 5° was observed in only 45% of cases. Although the range of wrist flexion and extension showed a correlation with dorsal tilt deformity, the range of forearm pronation and supination did not correlate with distal radius deformities.