Study of the patient's subsidence after revision hip arthroplasty by assessing gross stem subsidence in the femoral canal.

The aim of this study is to evaluate the M-Vizion modular stem performance in patients who undergo total hip replacement according to the standard practice. It is expected that subjects receiving revision hip arthroplasty with the Medacta M-Vizion™ modular hip stem will have less than 5mm of stem subsidence at 2 years.

Inclusion Criteria:

• Must be able to read, understand, and provide written informed consent on the Institutional Review Board (IRB) approved Informed Consent Form (ICF).
• Ability to understand and provide written authorization for use and disclosure of personal health information.
• Subjects who are able and willing to comply with the study protocol and follow-up visits.
• Patients requiring a revision total hip replacement.
• Subjects undergoing revision THA who will receive an M-Vizion femoral component according to the indications for use.
• Male and female patients ages 21 - 80 years of age at the time of surgery.

Exclusion Criteria:

• Patients with neuromuscular or neurosensory deficiency, which would limit the ability to assess the performance of the device.
• Patients with a systemic or metabolic disorder leading to progressive bone deterioration.
• Patients bone stock is compromised by disease or infection, which could possibly prevent adequate support and/or fixation to the prosthesis.
• Patients with an active or suspected latent infection in or about the hip joint.
• Patients that are incarcerated.

Patients listed for revision THA receiving a M-Vizion femoral component and meeting all inclusion/ exclusion criteria at a research site,