DePuy Orthopaedics has issued a voluntary recall of the ASR hip replacement system due to a higher than expected revision rate reported in the England/Wales and Australian national joint registries. There are two types of ASR hip implants used for total hip replacement surgery:

• ASR XL Hip System
• ASR Hip Resurfacing System Massachusetts General Hospital (MGH) in Boston, USA is the study sponsor. MGH is conducting this study with the help of funding from DePuy Orthopaedics. MGH will collect and analyze clinical information from 5,000 subjects around the world. The countries include the United States of America, Australia, South Africa, England, Denmark, Finland and Sweden. MGH will collect and analyze blood test results, X-rays, soft tissue imaging and how well the ASR hips are functioning. MGH will analyze the data annually for 6 years.

The purpose of this study is to follow patients who have the ASR hip system for the next 6 years. The findings of this study may help surgeons to make better informed decisions about monitoring and treatment of patients with ASR hip systems.

Description of the Subject Population:

• Adults who have previously undergone a surgery implanting the DePuy ASR XL Acetabular Hip System or ASR Hip Resurfacing System;
• ASR patients who are already being followed-up by their surgeon at least once a year. This routine follow-up care consists of a clinic visit, blood tests, X-rays and possibly an MRI, Ultrasound or CT scan.

Inclusion Criteria

1. Any patient with on-label use of the ASR-XL or ASR component system currently implanted.
2. Able to provide informed consent previously approved by institution's Institutional Review board (IRB) or ethics committee (EC).
3. Able to return for follow-up.
4. Able to complete the required patient reported outcome measures.

Exclusion Criteria

1. Any patient with off-label use indications for the ASR-XL or ASR component system.
2. Any patient who received the ASR-XL implant as a result of a hip resurfacing conversion or a revision THA.
3. Subjects with difficulty in comprehending the Informed Consent Form for any reason.
4. The subject refuses to allow their medical records to be inspected by the Sponsor, representatives of the Sponsor, or the medical office staff.

Adult patients with DePuy ASR or ASR-XL hip implants