Scapholunate Kinematics After Combined Palmar and Dorsal Ligament Reconstruction: A Quantitative Evaluation Using Four-Dimensional Computed Tomography.

Abstract

This observational pilot study investigated (1) carpal positioning in the neutral wrist pose, (2) the scapholunate (SL) rotation axis, (3) physiological SL motion, and (4) the SL distance after combined palmar and dorsal SL ligament reconstruction using quantitative four-dimensional computed tomography (4D-CT) imaging. Six subjects were included, and 4D-CT images of both wrists were obtained. Kinematic parameters of the treated side were compared to those of the healthy contralateral side, which was used as the normal reference. Average follow-up was 18.3 months (range, 8-35). After surgery, an average residual rotational deviation of the scaphoid (10.0° flexion, 8.1° radial deviation, 7.1° pronation) and lunate (17.5° extension) at neutral position of the wrist was observed compared with the contralateral side. Scapholunate motion followed that of the healthy wrists, whereas SL motion of one untreated affected wrist deviated from normal. Scapholunate distance was on average 1.3 mm larger than in the healthy wrists during flexion-extension and radioulnar deviation. Combined palmar and dorsal SL ligament reconstruction seems to restore wrist kinematics, although the neutral position of the scaphoid and lunate are not restored to normal. Therapeutic V.