Ultimate strength parameters of ten clinically significant human wrist ligaments

Ten clinically significant human wrist ligaments were tested to determine strain, force, and stress values at ultimate strength. Five ligaments from each functional group were tested: intrinsic (scapholunate, lunotriquetral, scaphotrapezium, deltoid capitoscaphoid, and capitotriquetral), and extrinsic (radiolunate, ulnolunate, radioscapholunate, radial collateral, and radiocapitate). The intrinsic ligaments were generally shorter and thicker than the extrinsic. Ligaments and associated bones were elongated axially at 100 mm/min to sequential strain intervals until beyond ultimate strength. The scapholunate and lunotriquetral, arguably the most critical ligaments, were strongest and stretched most at ultimate strength. This study demonstrates that in general, the more clinically critical intrinsic ligaments support greater loads and strains at ultimate strength.<>