Effect of excision of the fat pad in total knee replacement surgery.
Research type
Research Study
Full title
Effect of excision of the fat pad in total knee replacement surgery. A randomised controlled trial.
IRAS ID
100327
Contact name
Joanne Banks
Contact email
Sponsor organisation
R&D Department, Royal Liverpool Hospital
Research summary
The infrapatellar fat pad is a structure that is located within the knee. It sits at the front of the joint, just deep to the patella ligament. The function of the fat pad is not understood.
During knee replacement surgery, some surgeons prefer to remove the whole of the fat pad to improve exposure, whilst other surgeons would rather cut away the minimum amount and preserve the bulk of the structure. This surgical step of removing the fat pad is only a very minor part of a total knee replacement procedure.
There is no research on whether removing the fat pad or not has any effect on the knee replacement. Surgeons that remove the fat pad argue that it improves exposure of the knee joint and it may make the procedure more efficient. Surgeons that retain the fat pad argue that it may decrease the level of postoperative pain and prevent patella baja (shortening of the patella ligament), which may be a cause of post operative pain.
Lay summary of study results: When people have a knee replacement, surgeons must decide whether to remove or keep a structure inside the knee called the infrapatellar fat pad (sometimes known as Hoffa’s fat pad). This small, fatty cushion sits just below the kneecap and is often removed to make surgery easier. However, some doctors worry that taking it out might lead to more pain or stiffness after surgery. Until now, studies have not been large enough or long enough to give a clear answer.
In this study, we compared two groups of patients having routine knee replacements: one group had the fat pad removed, and the other group kept it. All patients received the same type of knee implants and recovery support. We followed them for two years after surgery and asked them to fill out questionnaires about their knee pain, symptoms, and ability to carry out daily activities. These included well-known tools like the KOOS and Oxford Knee Score.
We found that both groups improved a lot after surgery, with less pain and better movement. Importantly, there was no significant difference between those who had the fat pad removed and those who did not. This means that either option is safe and reasonable, and the decision can be based on the surgeon’s preference or the needs of the operation. Patients can be reassured that whether or not the fat pad is removed is unlikely to affect their long-term recovery.
REC name
North West - Liverpool Central Research Ethics Committee
REC reference
13/NW/0368
Date of REC Opinion
7 Aug 2013
REC opinion
Further Information Favourable Opinion