Hip resurfacing represented less than 1% of the total hip arthroplasty procedures in our sample, as surgeons have moved away from the metal-on-metal articulations that predominated (Figure 19). This procedure remains highly concentrated among both hospitals and surgeons; in 2015, resurfacing was done in only 48 AJRR hospitals by 63 surgeons. One surgeon accounted for 117 of the 448 resurfacing procedures (26%), while another performed 52 procedures (11.6%). The majority (86.1%) of the resurfacing procedures were performed on males, consistent with

the practice in registries worldwide 7,8.