Abstract
Background The scapholunate interosseous ligament (SLIL) couples the scaphoid and lunate, preventing
motion and instability. Prior studies suggest that damage to the SLIL may significantly
alter contact pressures of the radiocarpal joint.
Questions/Purposes The purpose of this study was to investigate the contact pressure and contact area
in the scaphoid and lunate fossae of the radius prior to and after sectioning the
SLIL.
Methods Ten cadaveric forearms were dissected distal to 1-cm proximal to the radiocarpal
joint and a Tekscan sensor was placed in the radiocarpal joint. The potted specimen
was mounted and an axial load of 200 N was applied over 60 seconds.
Results Sectioning of the SLIL did neither significantly alter mean contact pressure at the
lunate fossa (p = 0.842) nor scaphoid fossa (p = 0.760). Peak pressures were similar between both states at the lunate and scaphoid
fossae (p = 0.301–0.959). Contact areas were similar at the lunate fossa (p = 0.508) but trended toward an increase in the SLIL sectioned state in the scaphoid
fossa (p = 0.055). No significant differences in the distribution of contact pressure (p = 0.799), peak pressure (p = 0.445), and contact area (p = 0.203) between the scaphoid and lunate fossae after sectioning were observed.
Conclusion Complete sectioning of the SLIL in isolation may not be sufficient to alter the contact
pressures of the wrist.
Clinical Relevance Injury to the secondary stabilizers of the SL joint, in addition to complete sectioning
of the SLIL, may be needed to induce altered biomechanics and ultimately degenerative
changes of the radiocarpal joint.
Keywords
contact pressure - radiocarpal joint - scapholunate interosseous ligament - scapholunate
joint - SLIL
