Radiographic measurements on the radio-carpal joint in distal radial fractures.

Radiography of 40 wrists with fractures in the distal part of radius was performed. In the lateral view the inclination of the radial joint surface was analysed in different degrees of pronation and supination. The central ray was directed 15 degrees proximally and the results were compared with those obtained with a perpendicular central ray. In the perpendicular projections even moderate differences in pronation or supination between two examinations could seriously alter the measured inclination of the joint surface of the radius. The projection with the central ray directed 15 degrees proximally highly significantly decreased the errors between the measurements when compared to the perpendicular projection. The joint surface was depicted more dorsally inclined than in the perpendicular projection.