Body mass characteristics of hip osteoarthritis patients experiencing aseptic loosening, periprosthetic fractures, dislocation, and infections after total hip replacement

This work assessed the body mass characteristics of a cohort of community dwelling adults requiring surgery for complications related to primary hip arthroplasty, among other factors. The specific aim was to identify the extent to which high body mass prevailed in the cohort as a whole, to identify a role for subnormal body mass in the pathogenesis of post-operative complications following hip joint arthroplasty, and to identify whether different complication types could be differentiated on the basis of body mass profiles. The subjects were males and females drawn from a representative sample of 1,040 hip osteoarthritis patients between the ages of 30–89 years hospitalized for purposes of primary hip arthroplasty or complications related to prior replacement surgery. An analysis of their medical records showed: 1) Approximately 20% of the present cohort was constituted by patients with various complications related to prior arthroplasties, or to general deterioration of their condition; 2) The most common reasons for their re-hospitalization were aseptic prosthetic loosening followed by infection, prosthetic dislocations, prosthetic and periprosthetic fractures, and second surgeries on the opposite hip; 3) The presence of a high body mass index differentiated those presenting with aseptic prosthetic loosening, periprosthetic fractures, and those with infected hips (p < 0.007). Those with infection diagnoses were significantly heavier on average than those with no infection, regardless of diagnosis, and more cases with a dislocation history were underweight, rather than overweight (p < 0.05). It is concluded, a small but clinically relevant proportion of obese or underweight adults with hip osteoarthritis who undergo primary total hip replacement may experience complications at higher rates than cases with normal body weight, despite the generally successful outcomes experienced by the majority of hip arthroplasty patients.