The best way to prepare for a knee replacement is to use the weeks before surgery for three jobs: get your leg STRONGER, get your home ready, and get your health in the best shape you can.
Exercise before surgery (often called prehab) gives modest gains, mainly in the first few months after the operation. Stopping smoking and getting blood sugar under control lower the risk of wound problems and infection. A ready home makes the first two weeks safer and calmer.
Your hospital may give you its own list. Follow theirs where it differs.
Prehab exercises
Aim for most days, with mild discomfort that settles within a day being acceptable. Stop anything that makes the knee much worse.
- Thigh squeezes: leg straight, tighten the front of the thigh and press the back of the knee down. Hold 5 seconds, 10 times
- Straight leg raises: lying down, tighten the thigh and lift the straight leg a hand’s height. 10 times
- Sit to stand: stand up from a chair without using your hands if you can, then sit down slowly. 10 times
- Heel slides: lying down, slide your heel toward you to bend the knee, then straighten fully. 10 times
- Stationary bike or walking: 10 to 20 minutes if the knee tolerates it, to keep your heart and lungs fit
- Practice with walking aids: if you’ve been given crutches or a walker, learn to use them on the flat and on stairs now, while you’re not sore
A knee that straightens fully and a strong thigh before surgery make the early weeks easier. You’ll do many of the same exercises afterward. See knee replacement recovery week by week and stiff knee after knee replacement.
Health steps that lower your risk
- Stop smoking: smokers have more wound problems and infections after joint replacement. Stopping at least 4 to 6 weeks before surgery, and staying stopped while you heal, helps most. Ask your doctor for support
- Control your blood sugar: if you have diabetes, your team may check your HbA1c, a blood test showing your average blood sugar over the past three months. If it’s high, surgery may be delayed until it’s better
- Weight: carrying a lot of extra weight raises the risk of wound and infection problems. Some surgeons ask for weight loss before operating. Any loss also eases the load on the new knee
- Teeth and skin: get dental problems sorted beforehand. Report any cuts, sores or rashes on the leg, as broken skin can delay surgery
- Medicines: take a full list, including supplements, to your pre-op appointment. Some blood thinners and other drugs need stopping before surgery. Only stop what your team tells you to
- Alcohol: cutting back in the weeks before helps healing and lowers the risk of falls
You can’t choose how your surgery goes. You can choose how strong, healthy and ready you are when you arrive.
Set up your home
- Clear the floor: remove loose rugs, cables and clutter between the bed, bathroom and kitchen
- Move things to waist height: put everyday items where you won’t need to bend low or reach high
- Pick your chair: a firm chair with arms, high enough that your hips sit above your knees
- Sleep downstairs if stairs are hard: at least for the first week or two
- Light the way: night lights between the bedroom and bathroom
- Stock up: ready meals in the freezer, basic groceries, and your usual medicines
Equipment
Many hospitals arrange an occupational or physical therapy check before surgery to tell you what you need. Common items:
- Walker or crutches: usually provided or advised by the hospital
- Raised toilet seat or toilet frame: makes sitting and standing easier
- Shower chair and grab bars: for safe washing
- Long-handled reacher and sock aid: for picking things up and dressing
- Ice pack or cold wrap: for swelling, always with a cloth between it and your skin
What to arrange
- Help at home: someone with you for at least the first few days, and help with shopping, cooking and pets for the first couple of weeks
- Transport: you won’t be able to drive for several weeks. Line up rides home from hospital and to physical therapy and follow-up appointments
- Physical therapy: book or confirm your sessions before surgery so there’s no gap
- Work: talk to your employer about time off and a plan for returning
What to bring to hospital
- Loose clothes: shorts or wide-leg pants that fit over a bandaged knee
- Supportive shoes: closed-back, non-slip, easy to get on, not flip-flops
- Your medicine list and medicines: in their original containers
- Glasses, hearing aids, phone and a long charger cable
- Your walking aid: if you’ve been given one already
- Your exercise sheet: and any paperwork from your pre-op visit
Still deciding whether now is right? See when is it time for a knee replacement and questions to ask before orthopedic surgery. The NHS also has a clear guide to preparing for knee replacement.
Call your surgeon’s team before surgery if
- You get a cold, flu, fever, chest or urine infection in the days before
- You have a cut, sore, rash or insect bite on the leg
- You’ve started any new medicine, especially a blood thinner
- Your knee suddenly becomes hot, red and swollen
Mention it at your pre-op visit if
- You live alone or care for someone else
- You’ve had a blood clot, or reactions to anesthesia, before
- You’re worried about managing pain, stairs or getting home
The operation takes an hour or two. The preparation shapes the months after it.