Knee Replacement Exercises
Knee replacement is a very successful operation for knee pain and disability, with the damaged, worn or diseased joint surfaces being replaced with metal and plastic components. It has some of the greatest improvements in quality of life of all medical interventions.
Knee replacement cost is higher than hip replacement and the numbers of people having knee replacements may be higher now, making this a major medical expenditure, with over 70,000 people having their knee replaced in England and Wales every year. Knee replacement complications can also be expensive, with longer periods of hospitalisation, repeat operations and an extended knee replacement recovery with longer term physiotherapy.
Knee replacement needs the patient to participate fully in the rehabilitation process. Once the knee surgery has been done the work has only just begun. Partial knee replacement may be offered if only one side of the knee, or compartment, is affected by the arthritis and is less costly with patients recovering more quickly and suffering less pain overall. A knee replacement surgery video can be very useful, if you can cope with the blood and carpentry, to understand what has been done and why you need to work hard after the operation to regain range of movement and strength.
Other sites with further information on knee replacement exercises are at eHealthMD and the American Association of Orthopedic Surgeons. Modern developments include more bespoke systems to match the size and shape of the patient's bones and joint to the replaced parts rather than use an off the shelf sizing system. The Signature knee replacement uses bespoke surgical guides manufactured from the data from a person's MRI scan of their knee.
Exercising the main muscle groups around the knee is very important both before and after having a total knee replacement. Work closely with your physiotherapist to set your exercise programme before you leave hospital.
Exercise regularly, for instance for 10 minutes 6-8 times a day. Do not spend all of your time exercising or your knee may become inflamed, swollen and painful.
It needs a mixture of rest and regular exercise, which will be uncomfortable. These exercises are for the initial period immediately after the operation and many more exercises could be appropriate later.
Exercise 1 for Total Knee Replacement
Static quadriceps exercise
To perform have your knee straight and tense up the front muscles of the thigh as if you are trying to straighten the knee and lift the heel. Hold for a few seconds then relax. Try not to tense up the buttock muscles or to try too hard. Sometimes doing the exercise with both legs at the same time will give the affected knee the right idea.
Inner range quads
This is an exercise I really like, as the correct muscles have got to be working.
Sit with your knee bent over a rolled up towel, high enough to be able to lift the heel off the ground. Tighten up the knee muscles and lift your heel off the ground. Try and get the knee completely straight when you do this. If you can’t do this fully it’s called an extensor lag.
Straight leg raise
Sit or lie with the leg out straight. Tighten the thigh muscles, straighten the knee and lift the whole leg six inches (15cm) up off the bed or floor. It’s important to keep the knee completely straight during this procedure. Hold for three seconds then lower slowly.
DO NOT do this if you have a total hip replacement on the same side. It puts too much force through the artificial joint.
Passive knee stretches/Knee hangs
Sit or lie with your leg out in front of you. Put the heel up on a block or pillow so that the the knee hangs in mid air. Let the knee stretch for five minutes, or less if it is too painful.
It’s common for the knee not to go completely straight after knee replacement. This is called a flexion deformity when it is due to a tight joint. It’s important to get the knee straight again as this allows the joint to function normally and reduces the chances of certain complications.
Knee bends on the bed
When you are on the bed you can practise this regularly, although some people find it difficult and much prefer the exercise below, either on a chair or edge of bed.
You can use a board for this exercise, and at home you can use a tray. Keep the heel down on the board and slide the foot towards you, bending the knee. Hold it at the full bend for three seconds then release.
Knee bends in the chair
Sit in a chair with your foot on the ground. Slide the foot firmly towards you and then release. Hold for three seconds each time in the fully bent position. Do not allow your hips to move, just the foot.
If this is difficult you can put a tray under your foot and use talcum powder or a wool sock on your foot to draw it backwards and forwards with less friction.