Inclusion Criteria:  patients ≥ 18 years-old both genders patients undergoing a primary total hip arthroplasty surgery with implantation of a cemented prosthesis (Exeter hip stem model or Müller straight stem model) patients with a diagnosis of hip osteoarthritis, operated by the Orthopedic Surgery and Traumatology Department at the Bellvitge University Hospital patients who signed the written informed consent.  Exclusion Criteria:  patients allergic to 99mTc-MDP radiopharmaceutical patients with claustrophobia patients with a background of an active septic process patients with a postoperative septic complication patients periprosthetic fracture or misalignment of the prosthetic component patients who have a total hip prosthetic implanted due to a subcapital femoral fracture