Use and outcomes of primary total hip arthroplasty among US Medicare recipients more than 65 years of age were investigated by means of physician and hospital claims for a 5% random sample during 1986 through 1989. Cases involving hip fracture or evidence of existing orthopedic devices in the hip were omitted. Use rates were higher for women than for men and were substantially lower for Blacks than Whites. Major complications (death, further hip surgery, infection pulmonary embolism) were uncommon. These data document the frequent use of total hip arthroplasty, and confirm the rarity of serious adverse outcomes. Further studies should investigate the lower use of total hip arthroplasty among Blacks.