Apparatus for adjustably positioning extremity or body part such as knees hands, or feet for a surgical procedure having a carriage with a base adapted to engage a track for sliding movement there along, an arm configured to fit to the base at a hinge secured by a pin, a socket formed by the joining of the base and arm configured to accept a ball of a holder generally adapted to engage and support the extremity upon which the surgical procedure is to be performed, and a clamp adjacent cooperating with the hinge to lock a position of the carriage along a track and to lock a holder of an extremity in a secure position. The carriage is configured to be tightened and loosed with by the movement of one handle, thereby forming a releasable lock to the ball in the socket and carriage position. The carriage is adapted to slide on a rigid frame when attached to an operating table or the like. The carriage and frame are configured to promote improved maintenance and sterilization by minimizing parts and having a construction that improves sterilization by disassembly, flash operating room, and other sterilization methods.
