Radiographic assessment of ligamentous injuries in distal radius fractures after open reduction and internal fixation

Objectives Concomitant ligamentous injury in distal radius fractures (DRF) may explain continued pain following surgery. The purpose of this study was to compare radiographic measurements assessing scaphoid translation in DRF after reduction, to measurements performed on normal radiographs. This may allow noninvasive evaluation of radiocarpal ligamentous integrity. Methods Fifty postoperative radiographs were evaluated. The distance between the ulnar border of the radial styloid and the radial border of the scaphoid was measured midway between the styloid tip and scaphoid base, and then divided by scaphoid width at the same level. The measured ratios were compared to previously established normal data, established radiographic measurements of fracture reduction, fracture characteristics and fixation methods. Results Radiographic scaphoid position measurements differed significantly from normals ( p = 0.0001). Fracture characteristics, surgical difficulty, and technique were not associated with scaphoid position. Conclusions Despite accurate surgical reduction, abnormal positioning of the scaphoid may persist. This may reflect ligamentous injury, which generates suboptimal clinical results. Identifying and addressing ligamentous injury during surgery may prevent the development of instability and improve outcome after DRF.