Carpal Alignment Evaluation Using Three-dimensional Computed Tomography

ABSTRACT

PURPOSE: The purpose of this study was to analyze carpal alignment and evaluate the interobserver reliability of the several parameters using three-dimensional computed tomography (3D-CT) in normal Koreans. MATERIALS AND METHODS: The study included 42 wrists with no history of wrist pain or abnormality by physical examination. 3D-CT scanning was performed with each patient in zero position; the arm abduction against the trunk; the elbow flexed 90degrees; the forearm in neutral position using the stabilizing device. The three observers measured the carpal alignment parameters including distal radius articular angle, radiolunate angle, radioscaphoid angle, radiocapitate angle, radio-3rd metacarpal angle, scapholunate angle, lunocapitate angle, luno-3rd metacarpal angle. RESULTS: The mean distal radius articular anglewas 12.8degrees+/-2.6degrees, the mean radiolunate angle was 0.9degrees+/-4.6degrees, the radioscaphoid angle was 54.4degrees+/-5.3degrees, the mean radiocapitate angle was 1.7degrees+/-2.1degrees, the mean radio-3rd metacarpal angle was -1.2degrees+/-2.5degrees, the mean scapholunate angle was 53.4degrees+/-7.8degrees, the mean lunocapitate angle was 0.8degrees+/-4.7degrees and the mean luno-3rd metacarpal angle was -2.1degrees+/-5.0degrees. All parameters have excellent interobserver reliability. CONCLUSION: The normal mean values and ranges of carpal alignment angles measured by using 3D-CT may be of assistance in the evaluation of carpal alignment in patients.