The effect of distal radius translation in the coronal plane on forearm rotation: a cadaveric study of distal radius fractures.

Purpose: To determine the effect of lateral translation of the distal radius in the coronal plane on forearm rotation after distal radius fracture.

Methods: Ten fresh cadaveric limbs underwent distal radius osteotomy just proximal to the distal radial-ulnar joint to simulate an extra-articular distal radius fracture. We used an Agee Wrist Jack external fixator to create increasing magnitudes of distal fragment lateral translation in 2-mm increments. Forearm rotation was measured using a 3-dimensional camera at each magnitude of lateral translation.

Results: Total forearm rotation for the intact specimen and 2, 4, 6, and 8 mm (maximal) radial translations was 186° ± 53°, 188° ± 54°, 189° ± 55°, 190° ± 57°, and 193° ± 59°, respectively. There was no significant difference for any magnitude of radial translation. The average maximal radial translation possible before radioulnar abutment was 8 ± 0.5 mm.

Conclusions: In this cadaveric model, translation of the distal radius fragment in the lateral direction had no effect on forearm rotation.

Clinical Relevance: At the level of the proximal border of the distal radioulnar joint, isolated distal radius translation does not significantly affect forearm rotation.