Effects of Surgical Repair or Reconstruction on Radiocarpal Mechanics From Wrists With Scapholunate Injury

Scapholunate dissociation (SL ligament disruption) due to trauma can cause changes in joint kinematics and contact patterns, which can lead to scapholunate advanced collapse (SLAC wrist) with secondary radiocarpal osteoarthritis (OA) [1]. The relationship between consequent abnormal mechanics and the onset of OA is not clearly understood, however elevated joint contact pressure is believed to be an associated factor. Knowing how injuries affect joint physiology and mechanics and how well surgical repairs restore the mechanics may improve surgical efficacy and help predict OA risk. Recently a method was proposed to measure joint contact mechanics from in vivo imaging data during functional loading [2]. The objective of this study was to compare radiocarpal joint mechanics (contact forces, contact areas, peak and average contact pressures) of injured and post-operative wrists to contralateral controls using MRI-based contact modeling. We hypothesized that average contact pressures and peak contact pressures would be higher in the injured wrists, and that these measures would decrease post-operatively.