A Multicenter, Post-Market Clinical Follow-up Study of Subjects With the REDAPT™ System Monolithic Sleeveless/Sleeved Stem and/or Fully Porous Acetabular Shell With XLPE Liner and/or Modular Shell Components Previously Implanted

Inclusion Criteria:

Subjects must meet all of the inclusion criteria to enroll in the study:

1. Subject was considered skeletally mature at the time of surgery and was at least 18years of age.

2. Subject has undergone hip arthroplasty with the REDAPT Fully Porous Acetabular Shellwith XLPE liner or REDAPT Modular Cup Components (with or without Staple, Slice andBlade Augments), and/or Monolithic Sleeveless Stem, and/or Monolithic Sleeved Stemand are at least 3 months post-implantation at this site.

3. Subject required surgery with REDAPT device chosen for one of the followingindications:

4. Advanced degeneration of the hip joint as result of osteoarthritis, avascularnecrosis, posttraumatic arthritis, rheumatoid arthritis, or dysplasia (or anyof the composites of these conditions).

5. Fracture-dislocation of the hip, femoral neck fracture or trochantericfractures of the proximal femur with head involvement that are unmanageableusing other techniques.

6. Revision THA

7. Subject is willing to consent to and to follow the study visit schedule (as definedin the study protocol and ICF), by signing the IRB/IEC approved ICF.

8. Subject is willing and able to participate in required follow-up visits at theinvestigational site and to complete study procedures.

Exclusion Criteria:

Subjects meeting any of the following exclusion criteria will be excluded from study participation:

1. Subject had an active infection - systemic or at the site of surgery.

2. Subject, in the opinion of the PI, has an emotional or neurological condition thatwould pre-empt their ability or willingness to participate in the study includingmental illness, mental retardation, drug or alcohol abuse.

3. Subject is known to be at risk for loss to follow-up or failure to return forscheduled visits.

4. Subject is incarcerated or is pending incarceration.

5. Subject is enrolled in another clinical study that would affect the endpoints of thestudy.