Siljander MP, Trousdale RT, Perry KI, et al. - In this study, implant survivorship, clinical outcomes, radiographic results, and complications were explored in patients with osteopetrosis undergoing primary total hip arthroplasty (THA). Between 1970 and 2017, researchers distinguished 7 patients (9 hips) with osteopetrosis who underwent primary THA utilizing our total joint registry. At index THA, the mean age was 48 years and included two males and five females. In this analysis, 8 years was the mean follow-up. The findings revealed that in patients with osteopetrosis, primary THA is correlated with good 10-year implant survivorship (89%), but a very high reoperation (58%) and periprosthetic femoral fracture rate (44%). According to the results, femoral fractures seem correlated with smaller intramedullary diameters.