Effectiveness and cost-effectiveness of cemented, uncemented and hybrid hip implant prostheses in the younger total hip replacement patient: a randomised controlled trial
Osteoarthritis
This study is a multi-centre, three-group, superiority randomised controlled trial with patient-level randomisation, internal pilot, embedded qualitative research and health economic analysis in patients under 70 years undergoing primary elective total hip replacement surgery. The study participants will be randomised using a web-based randomisation system (sealedenvelope). Patients undergoing primary elective total hip replacement surgery will be randomised to receive either a cemented (reference), uncemented or hybrid hip implant prosthesis. Cemented - both the femoral and the acetabular components are attached to the bone with cement. Polymethylmethacrylate or bone cement is used to fix the stem and the cup in position. Surgeons can use any brand and type of cement. Uncemented - The femoral and acetabular components attach to the bone by osseo-integration (bonding at a molecular level directly between bone and implant). They are usually press-fit and rely initially on a tight fit of the implants within the bone. Hybrid - the femoral component is cemented, and the acetabular component is uncemented. It allows for a variety of uncemented acetabular bearing surfaces including ceramics but paired with a cemented stem.
1. Between 18 and 69 years of age (inclusive) at the time of screening 2. Undergoing primary elective THR due to osteoarthritis (patients may also have other indications for THR in addition to osteoarthritis)
Current key exclusion criteria as of 11/05/2026: 1. Receiving primary THR for reasons other than osteoarthritis (e.g., rheumatoid arthritis, etc.) 2. Patients requiring custom-made implants 3. Non-elective patients 4. Patients who lack capacity 5. Patients paying privately for their surgery 6. Prisoner 7. Patients undergoing 2-stage THR 8. Patients who have previously been randomised to the HIPPY trial _____ Previous key exclusion criteria as of 21/10/2025: 1. Not willing to consent 2. Receiving primary THR exclusively for reasons other than osteoarthritis (e.g., rheumatoid arthritis, etc.), 3. Patients requiring custom-made implants, 4. Non-elective patients 5. Patients who lack capacity 6. Patients paying privately for their surgery (including patients using health insurance) 7. Prisoner 8. Patients who have previously been randomised to the HIPPY trial _____ Previous key exclusion criteria: 1. Not willing to consent 2. Receiving primary THR exclusively for reasons other than osteoarthritis (e.g., rheumatoid arthritis, etc.), 3. Patients with dysplastic osteoarthritis requiring custom-made uncemented implants, 4. Non-elective patients 5. Patients who lack capacity 6. Patients paying privately for their surgery (including patients using health insurance) 7. Prisoner