HIP REPLACEMENT PROSTHESIS WITH HIGHLY CROSS-LINKED POLYETHYLENE HEAD

摘要

This invention corresponds to a prosthesis for total hip or hip resurfacing replacement, comprising a prosthetic femoral head made of highly cross-linked polyethylene, with a diameter ranging from 38 mm to 64 mm, to articulate with a cup or acetabular component made of metal. When the invention applies for total hip replacement, the polyethylene head includes a metal or ceramic core, which contains inside the female counterpart (14) to mate with the male counterpart (13) of a Morse taper located at the upper end of the femoral component. Said core has a safe intra-prosthetic anti-rotational locking mechanism to assemble the polyethylene head. The use of this type of head for total hip replacement, articulated with an ultra-polished acetabular cup, reduce the risk of dislocation, transmits less angular and torque forces to the Morse taper than large metal heads, and avoids problems related to the metal-metal bearing or with the use of large metal heads with thin polyethylene.When the invention relates to hip resurfacing replacement, the highly cross-linked polyethylene femoral head has a metal stem integrated into a metal-back (152), safely assembled to the polyethylene head. Using these types of heads for hip resurfacing replacements eliminates the problems associated with metal-on-metal resurfacing replacement.