Biomechanical analysis of the normal and reconstructed human hand: Prediction of muscle forces in pinch and grasp

In this work we present a biomechanical model of the normal and reconstructed human hand. The objective of this model is to predict muscle forces during the following three tasks: tip pinch, key pinch and grasp. The model takes into account all the available tendons in the fingers. Two common tendon transfers, to reconstruct the pathological hands, are then simulated. The brachioradialis BR transferred to flexor pollicis longus FPL to restore the thumb flexion and the extensor proprius of the index finger EIP transferred to extensor pollicis longus EPL to restore extension and abduction of the thumb. A non linear optimization approach was used to predict the optimal combination of tendons that maximized pinch and grasp strength after repairing hand.