The investigators will collect data of patients treated surgically for impending or pathological fracture of the proximal femur due to bone metastases between 01/01/2000 and 31/12/2023 with IMN or THA or HHA or MegaTHA or Mega.

After pre-screening the databases of the respective sites, the investigators expect to find approximately a total of 600 patients. A review will be made from the medical records, radiological imaging, and histological data of partecipants.

Inclusion Criteria:

• Male and female adult patients surgically treated between 01/01/2000 and 31/12/2023 in Rizzoli Orthopaedic Institute and in Massachusetts General Hospital.
• Age ≥18 y (at the time of surgery)
• Patients with impending or pathological fracture due to bone metastases of the proximal femur (head/neck, intertrochanteric, subtrochanteric area).
• Patients who underwent either IMN or THA or HHA or Mega or MegaTHA.
• Patients with available clinical and imaging data.

Exclusion Criteria:

• Patients with pathological or impending fracture of proximal femur due to primary bone tumor.

Male and female adult patients surgically treated between 01/01/2000 and 31/12/2023 in Rizzoli Orthopaedic Institute and in Massachusetts General Hospital.