Knee replacement recovery timeline: stages, milestones and warning signs

The NHS says it may take several months or longer to fully recover from a knee replacement and that this varies with age and general health. It also says recovery from a partial knee replacement should be shorter than from a total one. Partial replacement is used when arthritis affects one half of the knee, and the NHS says the cut is smaller and recovery quicker.

Arthritis UK explains that your new knee will continue to improve for as much as two years after the operation as scar tissue heals and the muscles are exercised. The early weeks are therefore about safe movement and pain control, and the later months about strength and confidence.

After surgery you spend time in a recovery room, where you may be given fluids and painkillers. Arthritis UK says pain is usually worst on the second or third day, when the anaesthetic and strong medicines wear off, and that without painkillers it is hard to do the exercises needed to rebuild strength and movement.

Nurses and physiotherapists help you start walking, with crutches or a frame at first. On an enhanced recovery programme the aim is to get you moving within 12 to 18 hours and home within four days, and Arthritis UK says if you have had minimally invasive surgery or are on that programme, this may be on the day of the operation. If you have had a spinal anaesthetic or nerve block, take care because feeling in the leg is reduced for a day or two.

Before you go, a physiotherapist or occupational therapist talks through dressing, showering, moving about and equipment. The NHS says compression stockings are usually given to wear to prevent blood clots.

The NHS says a nurse takes out stitches or clips after about 10 days and that there is a follow-up appointment about 6 weeks after the operation. Most people wear compression stockings for at least 6 weeks and take them off only to wash them.

For walking, the NHS advises using crutches or walking sticks at first, going down to one crutch and then a stick when you feel confident, and trying walking without an aid after about 6 weeks if you feel ready. Arthritis UK says the thigh muscles are weak after the operation, so falling could damage the joint, and says you should be able to walk outside within three weeks if you wear supportive shoes.

Day-to-day limits are set out by both sources. Do not sit with your legs crossed for the first 6 weeks, do not sleep with a pillow under the knee, avoid twisting, avoid heavy household jobs such as vacuuming or carrying shopping for the first 3 months, and keep the leg raised to reduce swelling. Arthritis UK suggests trying to kneel on a soft surface after three months, noting kneeling may never be completely comfortable.

Arthritis UK describes what is normal. Pain from bruising is expected in the first two months, and many people still need painkillers at six weeks to sleep through the night. Some pain may last as long as six months, and if it persists after that you should speak to your physiotherapist or GP.

Swelling is very common after knee replacement, especially around the ankle and foot, and may last for up to three months or so. Ice for up to 20 minutes at a time, with skin protected from direct contact, and raising the foot can help, but Arthritis UK stresses getting up to walk around for at least five minutes every hour to reduce clot risk.

Stiffness can develop for no obvious reason in the weeks after surgery. Continuing the exercises matters, and if stiffness has not improved after about six weeks the surgeon may need to manipulate the knee under anaesthetic.

The NHS says to ask for an urgent GP appointment or call NHS 111 if you have recently had a knee replacement and develop throbbing or cramping leg pain, a high temperature or feeling hot, cold or shivery, oozing or pus from the wound, or redness, tenderness, swelling or pain in the knee that is not getting better or is getting worse. These could be signs of infection or a blood clot.

Call 999 or go to A&E if you have pain and swelling in the leg together with difficulty breathing or chest pains, as this could be a clot in the lungs. Do not drive yourself.

Arthritis UK also advises looking after your feet, and seeing a doctor or podiatrist for problems such as ingrown toenails that could become infected.

The NHS says most people find daily life improves, though some have ongoing issues such as problems bending the knee, ongoing pain and stiffness, or instability, and that physiotherapy and certain exercises may help. It says most knee replacements last about 25 years and that another replacement later in life is not common.

Arthritis UK mentions a research study looking at targeted physiotherapy for people who are struggling six weeks after surgery, which is a reminder that if progress stalls, you should tell your physiotherapist or surgeon rather than waiting.