Abstract: A motor drive system and linkage arrangement for a hand prosthesis, wherein the prosthesis has at least one finger member extending generally tangentially with respect to a worm gear wheel secured to the prosthesis and driven by a drive motor and a worm gear located longitudinally within the finger to engage the teeth of the tangential worm gear wheel. When the drive motor runs the worm gear, the finger moves around the worm gear wheel toward or away from another finger member and/or a natural finger to open and close the prosthesis hand's grip. In an alternate embodiment, the drive motor and worm gear arrangement contained in one finger is connected by a linkage to the root portion of at least one other motorless finger mounted for pivotal movement on the prosthetic hand.