A Novel Passive Implantable Differential Mechanism to Restore Individuated Finger Flexion during Grasping following Tendon Transfer Surgery: A Pilot Study

Tendon transfer surgery is often used to restore hand grasp function following high median-ulnar nerve palsy. This typically reroutes and sutures the tendon of extensor carpi radialis longus (ECRL) muscle all four flexor digitorum profundus (FDP) tendons hand, coupling them together. makes it difficult irregularly shaped objects. We propose inserting a novel implantable passive device between FDP surgically construct differential mechanism, enabling fingers individually adapt irregular contours during grasping. These implants with no moving parts are fabricated from biocompatible materials. tested implants’ ability create flexion index middle when actuated by single in two human cadaver hands using computerized closed-loop control paradigm. In these cadaveric models, enabled significantly more for wide range donor tensions. The also redistributed fingertip forces fingers. When grasping uneven objects, difference contact reduced nearly 23% compared current suture-based surgery. results suggest that self-adaptive possible transfers drive multiple distal tendons.