Sagittal wrist motion of carpal bones following intraarticular fractures of the distal radius.

Forty patients (mean age, 37 years) with intraarticular C2 and C3 Colles fractures were treated by open reduction, internal fixation and bone grafting. At a mean follow-up of 8 years radiocarpal and midcarpal motion was evaluated, the depth of the articular surface of the distal radius in the sagittal plane was measured and the presence of arthritis was noted. The fractures healed with a mean palmar tilt of 6 degrees , a mean ulnar tilt of 18 degrees and ulna variance within 1 mm of the contralateral side. The depth of the articular surface of the distal radius was 1.3 mm greater than the uninvolved side. Measurement of carpal bone angles relative to the radius in maximum flexion and extension revealed lunate extension of 23 degrees , lunate flexion of 15 degrees , capitate extension of 62 degrees , capitate flexion of 40 degrees . There was a significant correlation between articular surface depth and radiocarpal motion.