الفهرس 
History of metal-on-metal total hip arthroplastyOnly 14 pages are availabe for public view
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Abstract
Metal-on-metal total hip arthroplasty has the longest clinical history of any of the currently used articular couples since it was first introduced by Philip Wiles in 1938 and McKee Farrar in 1951. They soon were abandoned because of poor performance regarding design flaws, high frictional torque, inadequate surface finish, early success of Charnley prostheses and high clinical failure rates. The failures were not due to the wear properties of the bearings.
Periprosthetic bone resorption and aseptic loosening are the major problems leading to failure, and bone loss compromises the results after revision surgery. Periprosthetic osteolysis is thought to be largely caused by debris released from the bearing surface of the polyethylene components that are in almost universal use. Implants with alternative articulations and no polyethylene bearing surfaces are therefore desirable.
The interplay of materials, macrogeometry (diameter and clearance), microgeometry (surface topography), and lubrication influences the wear of metal-on-metal bearing total hip replacements to a greater degree than with metal-on-polyethylene bearings. For metal-on-metal bearings, in distinction from conventional polyethylene bearings, larger diameters can actually produce lower wear rates for similar manufacturing parameters.
Metal-on-metal bearing couples have advantages over implants that use polyethylene. The most important advantage is the considerably less linear and volumetric wear shown in simulator testing and clinical retrievals and therefore marked reduction in osteolysis. Also the use of large diameter heads increases the displacement distance that must be traversed before luxation to occur, thereby increasing joint stability as well as the range of motion.
The clinical outcomes associated with contemporary total hip systems with metal-on-metal bearings have generally been good and there are no reports of reoperations for a problem directly attributable to the metal-on-metal articulations. The current generation of implants has only early and mid-term results available, with no long-term series yet published. Therefore, although a metal-on-metal bearings may be considered a viable alternative to polyethylene implants, outstanding and unresolved issues continue to exist with this bearing, as they do with the alternatives.
Concerns remain with the long-term biological effects of the elevated metal ion levels found in all patients with metal-on-metal bearings in situ. With the available evidence in the literature there is nothing to prove or deny any deleterious effect of the rise in metal ions following the implantation of MOM prosthesis.