Who we are  

We are a group of clinicians, researchers, and patients, working collaboratively to understand how the decisions around choosing implants for people undergoing hip replacement are made and find out which implants are best for those under 70 years of age. 

HIPPY is a study funded by the National Institute for Health and Care Research under their Programme Grant for Applied Research funding stream. It started on 1st July 2023 with circa £3 million allocated to this programme. It is sponsored by North Bristol NHS Trust and led by Elsa Marques (University of Bristol) and Professor Ashley Blom (Vice President of the University of Sheffield) in collaboration with Sheffield, Exeter, Northumbria, and the Southwest London Elective Orthopaedic Centre. It includes the world’s largest trial in orthopaedic implants in which close to 8,000 patients will be randomised, supported by the Bristol Trials Centre. 

Why is this research important 

Total hip replacement is clinically cost-effective for the treatment of osteoarthritis. More than 100,000 primary hip replacements were performed in the UK pre-pandemic and the NHS is expected to surpass these soon. Three quarters of hip replacements last 15-20 years; nearly 60% of hip replacements last 25 years. When an implant fails, it often requires revision surgery which seriously affects patients function and quality-of-life. In the next decade, the NHS will spend over £6 billion on primary hip replacements, including £1.2 billion on implants, and £900 million on revision surgery. 

Primary hip replacement involves replacing a damaged hip joint with an artificial implant that has two main parts. One part goes into the thigh bone (femur) and ends in a ball which fits into a socket or cup attached to the pelvis, making a ball-and-socket joint. Implants can be fixed to bone with cement (cemented), without cement (uncemented), when the implant in the thigh is fixed with cement and the socket or cup is uncemented, this is called a hybrid hip replacement. Cemented hip implants are safe, inexpensive, have a long track-record, and offer the best value-for-money for men aged over 75 and women aged over 65 years. There is no high-quality evidence from a trial to suggest uncemented or hybrid implants are better than cemented implants for younger patients, and these are often more expensive. Yet three quarters of NHS patients aged under 70 years receive uncemented or hybrid implants.  

What we are doing 

We will undertake several studies over 5 work packages:  

A national survey of orthopaedic surgeons and hospitals and we will talk to surgeons, hospital managers, and patients to understand:  

Would you like to get involved? 

We would love to hear from you! If you are: 

• a hip surgeon who would like more details and how to take part in the studies
• a hospital and would like your centre to take part
• responsible for procuring hip implants at your hospital and would like to talk to us 

There are many ways in which you can contribute and take part in our research. Please contact our research team at: hippy-programme@bristol.ac.uk

HIPPY Research Studies

‌Understanding how choices of implants are made by surgeons, hospitals, and patients