A system for transporting and positioning a patient onto an operating room table from a movable transportation device, e. The transmission family members include three planetary gear sets having seven torque-transmitting mechanisms and three interconnecting members. In a preferred form, polyamide-ionomer graft copolymers have a polyamide component backbone and ionomeric components grafted thereto. Distal portion has an axial length, a threaded exterior with a root that tapers toward the drilling tip, a crest diameter substantially smaller than the proximal portion crest diameter, and a thread height substantially smaller than the proximal portion thread height portion.