Morbid obesity and excessive hospital resource consumption for unilateral primary hip and knee arthroplasty.

Two objectives of this study were (i) to estimate the number of primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) performed on morbidly obese people in the United States, and (ii) to estimate the economic impact of morbid obesity on hospital resource use. In 2006, approximately 2.9% (6713 cases) of primary THA and 4.2% (20,964 cases) of primary TKA recipients were diagnosed as morbidly obese. Despite the controversy associated with increased infection risk and failure rate, a large number of morbidly obese people seem to consider that the benefits outweigh the risks. When sex, age, race, and primary payer were held constant, the hospital resource consumption for unilateral primary THA and TKA was 9% ($1432) and 7% ($1025) higher among morbidly obese patients than among nonobese patients, respectively.