RT Journal A1 Jacobs, Joshua J. T1 The Utility of MARS MRI in Patients with Metal-on-Metal BearingsCommentary on an article by Alister J. Hart, MA, MD, FRCSG(Orth), et al.: “Pseudotumors in Association with Well-Functioning Metal-on-Metal Hip Prostheses. A Case-Control Study Using Three-Dimensional Computed Tomography and Magnetic Resonance Imaging” JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 2012 FD February 15 VO 94 IS 4 SP e26 1 OP 2 DO 10.2106/JBJS.K.01602 UL http://dx.doi.org/10.2106/JBJS.K.01602 AB Metal-on-metal bearings for total hip arthroplasty have a long history of use that dates back to the introduction of the McKee-Farrar prosthesis in the 1960s. Metal-on-metal bearings ultimately fell out of favor because of the excellent clinical results of the Charnley low-friction arthroplasty concept, which employed metal-on-UHMWPE (ultra-high molecular weight polyethylene) bearing surfaces. However, the use of metal-on-metal bearings was revisited in the 1990s as polyethylene-associated periprosthetic osteolysis emerged as a major clinical problem limiting the longevity of hip reconstructions in high-demand patient populations.