Autograft replacements for the scapholunate ligament: a biomechanical comparison of hand-based autografts

An ideal replacement for the scapholunate ligament (SLL) has not been found. The carpometacarpal bone-ligament-bone complex at the base of the second and third metacarpal is proposed as a replacement for the SLL in this study. A cadaveric study of matched SLL, second metacarpal-trapezoid ligament, third metacarpal-capitate ligament, and dorsal periosteal retinaculum was performed. Stiffness and strength were obtained from fresh-frozen specimens tested to failure with a hydraulic distractor. The second metacarpal-trapezoid ligament and the third metacarpal-capitate ligament most closely approximated the stiffness and strength of the SLL. The dorsal periosteal retinaculum was significantly less stiff and was significantly weaker than the SLL. This study indicates that the second or third carpometacarpal ligaments are grafts that approximate the mechanical properties of the SLL.