Joint PREP study

Hip and knee replacements are common operations for patients with osteoarthritis. It is a major operation with a long recovery period. One-third to one-half of people waiting for hip or knee replacements are frail (physical vulnerable e.g., lower strength and less mobile) and may experience more complications and longer hospital stays.

Evidence suggests that an improved diet with extra protein and pre-operative exercise may lead to fewer post-operative complications and faster recovery. However, no studies have looked at pre-operative protein and exercise in frail individuals undergoing hip or knee replacement in the NHS. ‌

Project aims

During this project we wanted to understand whether it would be feasible to use a randomised controlled trial to evaluate a prehabilitation programme for frail adults undergoing hip or knee replacement.

A randomised controlled trial is a study during which different treatments are tried out on a group of participants. A prehabilitation programme is aimed at getting a patient ready for surgery by improving their fitness and overall health.

What we did

We wanted to see if the intervention we were trialing could improve recovery from surgery in frail older people having hip or knee replacement. We provided patients with a personalised home exercise programme and daily protein supplements. We asked them to carry out these exercises and take their supplements for 12 weeks before their joint replacement surgery.

To understand if our approach would work, we first needed to see if people would be willing to take the supplements and carry out the exercises we suggested. We did this by running a small study, called a ‘feasibility study’.

What we found and what this means

Study participants found our programme acceptable. This means that evaluating it with the help of a larger trial could be possible.

More importantly, we identified some adjustments that would need to be made to optimise how this potential future trial would be designed.

For example, we found that the exercises given to patients were too challenging for some of them. This means a future trial would have to include easier exercise options and make sure the work is tailored to individuals’ abilities.

Our findings also suggested that participants could potentially be more likely to keep taking their protein supplements if we provided them with additional suggestions on how to make them taste better.