Within 7 to 10 days after your knee replacement, you should be able to get your knee entirely straight/full extension (Fig. 1) (no space between the back of your knee and the table) and you should be able to bend/flex your knee to at least 90 degrees (Fig. 2). 90 degrees is the same thing as a right angle.
The typical recovery trajectory demonstrates flexion AROM between 70 and 90 degrees (interquartile range) immediately following surgery, 95–115 degrees 1 month following surgery, and 109–122 degrees 3 months following surgery.
On average, most individuals have around 0 degrees of knee extension (a fully straightened knee) and 135 degrees of knee flexion. This can vary based on how tall you are and how big your muscles surrounding your knee are.
One to three weeks after surgery
Typically, you'll be able to bend your knees at a 90 degree angle, fully straighten your knee, and walk for at least 10 consecutive minutes during this stage of physical therapy.
Much of the lack of knee flexion immediately after surgery is not only due to pain, but also knee swelling or edema in response to the surgery. Inside of your knee is a joint capsule that surrounds the entire joint, imagine this joint capsule is shaped like a balloon.
This is normal during the early stages of recovery, as the knee experiences swelling which causes temporary stiffness. This should begin to subside within the first month or so after the operation; if it continues to feel stiff or if the stiffness gets worse, contact your surgeon.
Although exercise is the key to healing, you could be backpedaling progress by overworking your knee. Signs of over-exercising include swelling of the entire leg and lingering pain that stretches into the evening or into the next day.
The best sleeping position when recovering from knee surgery is on your back with your leg supported by a pillow. If you prefer side sleeping, prop up the recovering knee with a body pillow between the legs. Avoid putting the leg in a position where the knee is bent or hyperextended.
Within 7 to 10 days after your knee replacement, you should be able to get your knee entirely straight/full extension (Fig. 1) (no space between the back of your knee and the table) and you should be able to bend/flex your knee to at least 90 degrees (Fig. 2). 90 degrees is the same thing as a right angle.
Walking. Proper walking is the best way to help your knee recover. At first, you will walk with a walker or crutches. Your surgeon or therapist will tell you how much weight to put on your leg.
Activities during which the knee is flexed beyond 90 degrees are known to place a greater load across the whole knee joint and potentially cause more damage to the articular cartilage (4–6). Several studies have reported that the risk of knee OA is increased by work that involves prolonged bending of the knees (7–9).
4 – 6 weeks after surgery
You would be able to walk for 10 minutes without any assisted devices within 4 – 6 weeks of the procedure. You shouldn't need cane, crutches, walker, and other assistive devices. Your physical therapist will encourage you to walk without an assistive device for longer distances gradually.
Nerve pain – The surgical incision that is made through the skin and underlying layers to get into the knee joint also cuts through small nerves that pass through these tissues. Commonly this leaves the outer aspect of the knee feeling a bit numb or tingly after surgery, or a feeling of a “tight band” around the knee.
Can you sleep on your side after knee replacement surgery? You can, but it's wise not to do so until at least a few weeks after surgery, when you can start bending your knee. Make sure you lay on your non-operative side. Sleeping this way makes sure no pressure falls on the knee you had surgery on.
Sleeping on the side can be painful because the leg is not straight enough. However, gradually, you can start sleeping on your side as the knee heals. But avoid sleeping on the operative side at all costs, as it puts a lot of pressure on the surgery site.
Ibuprofen has been shown to have an irreversible effect on the healing of fractures. Also the inhibitory effect of these drugs on fracture healing is greater the longer the duration of use.
Within 2-3 weeks post surgery, you should be able to walk a short distance – or for around 10 minutes – without depending on a mobility aid. About 4-6 weeks after surgery, you'll likely be cleared to go back to work as normal, if you have a sedentary occupation.
Most patients can walk on their own roughly four to eight weeks after knee replacement.
In general, avoid sports that require jerking, twisting, pulling, or running. You should be able to do lower-impact activities, such as hiking, gardening, swimming, playing tennis, and golfing.