3 dimensional finite element analysis of the human wrist joint without ligaments under compressive loads

Damage of carpal ligaments is very common in daily living. Yet its mechanical behavior on the carpal bones is unclear when the ligaments are omitted from the carpal joints. In this study, our goal was to perform a computational analysis of the carpal biomechanics without ligaments. A three-dimensional finite element model of the wrist was constructed which includes the carpal bones, the cartilages and the proximal metacarpals. All of the bones were modeled with the cartilage layers smoothly embedded in them. 100-Newton pressure load was applied to the upper section of the second and the third metacarpals. The effect of dividing ligaments on the contact stress distribution in the Radio-Scaphoid, the Radio-Lunate and the mid-carpal joints were studied. By dividing the ligaments, all the carpal bones are moved to the radius direction. Therefore the contact stresses in the radio-scaphoid & the radio-lunate are increased. Furthermore, the contact stress between the mid-carpal joints changed little.