The aim of hip replacement surgery is to re-establish the physiological hip function and to obtain a stable fixation between the prosthetic components and the native bone. Commonly, the fixation is obtained by bone ingrowth between the prosthesis and the native bone. Thus, the quality of the patient's bone stock is essential to achieve this aim. However, several clinical conditions may impair the bone stock; therefore, in these cases bone grafts are necessary to improve the prosthetic fixation. The gold standard is represented by autologous bone grafts (from iliac crest or from acetabular bone chips) or allogeneic bone grafts from cadaveric femoral heads. Nevertheless, the osteogenic potential of multipotent cells derived from different anatomical regions has never been examined.

Thus, the aim of this study is to isolate multipotent cells from acetabular or femoral bone chips and from bone marrow aspirate of the same patient and to compare their osteogenic potential. The results of this study may reveal differences, which may have a clinical relevance for hip replacement surgery.

Inclusion Criteria:

• Patients undergoing hip replacement and affected by:

  1. hip osteoarthritis
  2. mild developmental dysplasia of the hip

• 18 ≤ Body Mass Index (BMI) ≤ 30 kg/m2

Exclusion Criteria:

• Rheumatoid arthritis
• Patients under pharmacological treatment for bone metabolic disorders
• Patient affected by metabolic disorders, which may affect bone metabolism
• Presence of bone metastases
• Presence of bone infections
• Patients undergoing hip revision surgeries
• Obesity (BMI ≥30kg/m2)

13 patients undergoing hip replacement surgery will be selected. Samples from acetabulum, proximal femur (head of the femur) and from bone marrow will be collected for each patient.