Thermoplastic PUR Gives ‘Midas Touch’ to Prosthetic Fingers

Partial Hand Solutions has developed prosthetic fingers using thermoplastic polyurethane (PUR) from RTP Company. ‘M-Fingers’ device from Partial Hand has been used as a prototype. The inner structure of the dexterous fingers and multi-position friction thumb is designed using RTP 2300-series glass-filled rigid thermoplastic PUR, which is over-molded with RTP 1200-series thermoplastic PUR elastomer to provide each finger with dexterity. The fingers and thumb have urethane over-molds to provide better grasp and in-molded finger nails for picking up small objects. The rigid PUR material gives strength and dimensional stability to the product. The mechanical fingers are actuated by a Spectra cable that crosses the wrist and is controlled by simple wrist flexion. M-Fingers are normally built using silicone partial hand socket with the appropriate number of fingers and finger sizes to match the sound-side hand. M-Fingers are distributed by Liberating Technologies of Holliston, MA.