A total knee replacement will follow the normal phases of wound healing. There is usually some overlap between phases, meaning that the one doesn’t stop completely when the next phase starts.
The first couple of days after your total knee replacement you will notice heat, swelling, redness and pain around your knee joint. Your pain will also be at its worst during this phase, so it’s important to use the medication as prescribed by your doctor. This phase usually peaks after 3 days.
Proliferation phase (+ 3 weeks)
The second phase of healing starts about 48 hours after your operation and lasts about 2-3 weeks. During this phase healing takes place, where scar tissue forms in and around your knee replacement. This may sound like a bad thing, but scar tissue is your body’s way of closing the wound and the start to regaining stability inside your knee joint.
Guidance from your physiotherapist is vital during this stage, because the healing tissue around your operation will still be quite fragile. The goal of the exercises and advice from your physiotherapist at this point after your knee replacement will be to support the healing process. Doing too much too soon can interfere with healing, but doing too little will result in stiffness and can interfere with how much movement you eventually regain in your knee joint. By now you should be able to walk, climb steps and get into/out of a chair with your crutches.
Remodelling phase (+ 6 weeks)
In the last phase of healing the scar tissue formed during the proliferation phase matures. This means that it isn’t as fragile and can tolerate more than during the early phases of healing. If you were seeing your physiotherapist regularly up to this point and completed your exercises, by now the muscles around your knee should already be strong enough to support your total knee replacement during everyday activities.
The process described above takes about 6 weeks, but there will be overlap from one phase to the next. During the first 6 weeks after your total knee replacement you will be seeing your physio about twice a week. By then you should have enough movement and strength in your knee that your exercises will maintain the improvement between sessions. This means that your physiotherapist will start seeing you once every week or two and, as you get stronger, once a month.
At the end of 6 weeks you should be able to start walking without crutches and put your full weight on your affected knee. Getting into and out of a car will still be slow, but you should be able to do this without help from someone else. Your knee might still be swollen at times, but this is normal and can still happen up to 6 months after your operation. You should be able to start driving at this stage, but that will depend on when your doctor gives you the go ahead.
At 12 weeks
Throughout your rehabilitation e will check on your progress, make sure that you don’t develop any muscle imbalances and clear your knee joint when you have completed rehabilitation. This means that you should have full extension (straightening) and almost full flexion (bending) of your knee. You should also be able to stand on the operated leg with your full weight without pain. After a total knee replacement this is generally at 12 weeks after your operation.
If you followed the guidance of your physiotherapist and did your part by sticking to your home exercises, your knee should be strong and flexible enough to do most of your normal day to day activities. This should include brisk walking, climbing stairs, getting up from a chair and strolling around in a shopping center. Even picking up a shoe or dropped pen should be possible. You should be able to do all of this without using a crutch or walking stick.
What about 6 months and onwards after the operation?
As time goes on your knee will keep getting stronger and you will get more confident in your activities. By the time you reach 6 months post-operatively you should be able to drive your car around town comfortably, climb stairs without hesitation and climb up and down a ladder.
At the one year mark you should be able to do things like drive longer distances, kneel in the garden, sit on the floor with your legs crossed and get up again without difficulty.
Full recovery after a total knee replacement can take up to two years after surgery. How long your recovery takes will depend on many different factors including the extent of the damage to your knee, how long you had the problem and how strong you were before the operation. After 18 months you should be back on the tennis court of golf course, hopping off the sidewalk and almost able to forget which knee gave you trouble in the first place.