An upper extremity prosthesis may include a prosthetic hand including a prosthetic thumb having a base and a tip, and a prosthetic index finger having a base and a tip. Actuators may be coupled to the upper extremity prosthesis. Prosthetic flexion tendons may have first ends operably coupled to the actuators and second ends coupled to the tips of the thumb and the index finger. Biasing systems may be operably coupled to the prosthetic thumb and the index finger. Upon actuation of the actuators in a first direction, the prosthetic flexion tendons cause the thumb and index finger to flex. Upon actuation of the linear actuators in a second direction opposite the first direction, the biasing systems cause the thumb and index finger to extend.