Biomechanical Analysis of Three Different Reconstruction Techniques for Scapholunate Instability: A Cadaveric Study

This study aimed to compare the biomechanical strength of 360° scapholunate interosseous ligament (SLIL) reconstruction only using an artificial material (AM), double dorsal limb (DDL) SLIL reconstruction only using AM, and the modified Brunelli technique (MBT) with ligament.

Eight cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate (RL) angle were recorded with MicroScribe. The SL distance was measured after dividing the volar and dorsal aspects. We utilized four different wrist postures (neutral, flexion, extension, and clenched fist) to compare five conditions: intact wrist, SLIL resection, 360° SLIL reconstruction using AM, DDL SLIL reconstruction using AM, and MBT SLIL reconstruction with ligament.

The dorsal SL distance in the SLIL resection was widened in all wrist positions. The dorsal SL distance was restored with all three techniques and in all wrist positions. The volar SL distance in the wrist extension position was widened in the SLIL resection condition. The volar SL distance was restored in the extension position after 360° SLIL reconstruction using AM condition. There were no statistically significant differences in SL and RL angles among the conditions.

All three reconstruction techniques could restore the dorsal SL distance. However, only the 360° SLIL reconstruction using AM restored the volar SL distance in the wrist extension position. DDL SLIL reconstruction using AM tended to overcorrect, whereas 360° SLIL reconstruction using AM effectively stopped volar SL interval widening.