Knee Replacement Surgery

Knee replacement, or knee arthroplasty, is a surgical procedure to replace the weight-bearing surfaces of the knee joint to relieve pain and disability. It is most commonly performed for osteoarthritis, and also for other knee diseases such as rheumatoid arthritis and psoriatic arthritis.  Knee replacement surgery can be performed as a partial or a total knee replacement. In general, the surgery consists of replacing the diseased or damaged joint surfaces of the knee with metal and plastic components shaped to allow continued motion of the knee. 

Causes Knee Joint Deterioration

Knee arthritis (inflammation of your knee joint) is a major cause of knee joint deterioration. The most common arthritis is osteoarthritis, which is inflammation related to wear and tear of the knee joint. Wearing of your knee joint is a common problem with ageing. However, certain conditions can accelerate the process of wear. Injury to your knee joint, surgical procedures, muscle weakness or increased body weight all accelerate the load and hence the wear and tear of the knee joint. Rheumatoid disease, gout or infection can also increase your joint wear and tear.

Symptoms of Knee Joint Arthritis

The obvious sign of wear and tear of the knee joint is pain. Knee pain can be achy or sharp and may be accompanied by swelling. Because your knees do not wear equally across the joint surface, a deformity may begin to appear over time. This can be both knock kneed or bow legged in appearance, or windswept knees (one of each). You may also find one or both knees lacking full movement, especially extension.

Knee Arthritis Diagnosed

Your physiotherapist or doctor will look for signs of limited knee movement and deformity, swelling and, importantly, knee pain. In most cases an X-ray will be sufficient to show the degree of wear and tear. An MRI may also be used to to exclude soft tissue pathology.

Treatment for Total Knee Replacement:

Pre Operative Physiotherapy:-

Pre-operatively you may be prescribed a course of physiotherapy to better prepare your knee and its surrounding muscles for the upcoming surgery. 

Post Operative Physiotherapy:-

Some patients who have a Total Knee Replacement (TKR) start to feel better within a few weeks of the surgery. Post-operative physiotherapy is important to regain full knee motion, strength and day to day function.

Your post-operative physiotherapy treatment will aim to:

1 Reduce knee pain and inflammation.

2 Normalise knee joint range of motion.

3 Strengthen your knee muscles: quadriceps (esp VMO) and hamstrings.

4 Strengthen your lower limb: calves, hip and pelvis muscles.

5 Improve patellofemoral (knee cap) alignment

6 Normalise your muscle lengths

7 Improve your proprioception, agility and balance

8 Improve your technique and function eg walking, stair climbing, squatting and bending

9 Minimise your chance of re-injury.

Risks of Knee Replacement Surgery:-

infection, persistent instability and knee pain, knee stiffness, and difficulty returning to your previous level of activity. 


1. Quadriceps Sets:-

*Tighten your thigh muscle. Try to straighten your knee. Hold for 5 to 10 seconds.

*Repeat this exercise approximately 10 times during a two-minute period, rest one minute, and then repeat. Continue until your thigh feels fatigued.

2.  Straight Leg Raises:-

*Tighten your thigh muscle with your knee fully straightened on the bed, as with the quadriceps set above. Lift your leg several inches. Hold for 5 to 10 seconds. Slowly lower.

*Repeat until your thigh feels fatigued.

*You also can do leg raises while sitting. Tighten your thigh muscle and hold your knee fully straightened with your leg unsupported. Repeat as above.

*Continue these exercises periodically until full strength returns to your thigh.

3. Ankle Pumps:-

*Move your foot up and down rhythmically by contracting your calf and shin muscles. Perform this exercise for 2 to 3 minutes, 2 or 3 times an hour in the recovery room.

*Continue this exercise until you are fully recovered and all ankle and lower-leg swelling has subsided.

4. Knee Straightening Exercises:-

*Place a small rolled towel just above your heel so that your heel is not touching the bed. Tighten your thigh. Try to fully straighten your knee and to touch the back of your knee to the bed. Hold fully straightened for 5 to 10 seconds.

*Repeat until your thigh feels fatigued.