Controversies in Large Metal-on-Metal Cementless Total Hip Arthroplasty

Over the last several years, many orthopaedic surgeons have embraced so-called alternative bearing surfaces in total hip arthroplasty, largely on the basis of the hypothesis that a reduction in the volumetric wear rates afforded by these improved articulating couples will reduce the prevalence of osteolysis and aseptic loosening, which in turn will improve implant survivorship. We conducted the study on an interval of 12 months. 19 cement less total hip arthroplasty using a metal-metal friction couple were consecutively implanted in 19 patients (6 female and 13 male) less than 55 years of age. We compared the reasults with a matched control group of cement less arthroplasties using ceramic-on-ceramic and metal - polyethylene articulation. The Harris hip score at follow-up (minimum 2 years) for the metal-on-metal was 95. After the same follow-up, the results of the ceramic-on-ceramic and polyethylene-metal were significantly different. With the same survival rates for both groups, the functional results (range of motion, stability and postoperative recovery) were significant increased for metal-on-metal bearing. In conclusion, we recommend this type of prosthesis for younger patients with an increased activity level, and a good quality bone stock., The position of the prosthetic cup is an important factor in the release and increased blood levels of metal ions. There are concerns regarding possible toxic effects of metal ions on pregnancy and hypersensitivity to metal ions. A greater follow-up and a greater setback are required to confirm the literature data, mostly encouraging.