Prehab before knee replacement, what it can and can't do
The weeks between booking a knee replacement and the day of surgery are often a waiting game. Prehabilitation, a structured exercise program before surgery, aims to turn that waiting time into preparation. But what does it actually change?
What the latest evidence shows
A 2025 meta analysis pooled 21 randomised trials with 2,150 people having knee replacement for osteoarthritis (Zhang et al., Frontiers in Medicine, 2025). Compared with usual care, prehab:
Reduced pain after surgery at one, three and six months, by roughly 1 to 1.4 points on a 10 point scale.
Slightly improved knee flexion at three months, by about 2.5 degrees.
Did not shorten hospital stays, and made little difference to early knee movement.
The authors concluded prehab effectively relieves postoperative pain and partly improves early function, but does not significantly affect length of stay.
Reading the results sensibly
A one point drop in pain for months after surgery matters to patients, and prehab is low risk and low cost. Its benefits are real, but modest. It is best seen as part of a well planned pathway rather than a single fix.
Prehab also has value the trials don't always measure. It gives patients a chance to learn their exercises before surgery, when they are not in pain or on strong medication, and it builds the habit of doing a home program.
Making prehab count
Start early. Use the waiting list period, not just the last fortnight.
Teach the post op program now. Patients who already know the exercises start rehab with confidence.
Keep it simple and home based. Strengthening, range of motion and walking suit most patients.
Track it. Adherence before surgery is a useful early sign of how a patient will manage after it.
BIBO supports the whole pathway, from prehab through to full recovery, so the program a patient starts before surgery carries on seamlessly after it.
This article is general information for health professionals and is not clinical advice.
