Knee injuries

These two terms are frequently misunderstood and used incorrectly and so I thought I would clarify things.

A knee replacement is when the actual knee is replaced with a prosthetic knee (made of metal and plastic) due to severe damage, commonly caused by arthritis. The most common type we see is a total knee replacement but nowadays there are more and more partial knee (half knee) replacements. Most often the person retains their kneecap (patella) but sometimes this is also replaced.
A knee reconstruction is when the knee is repaired. The most common we see is an anterior cruciate ligament (ACL) reconstruction. This is the most famous one that we hear about during the footy season. The injury involves a complete rupture of the ACL, which is a ligament that is required for stability of the knee. The ligament is replaced with another ligament either made from the hamstring tendon or the patella tendon or a synthetic tendon may be used (LARS ligament).

After both procedures, intensive rehabilitation is required. Initially rehabilitation is focused on increasing the movement of the knee. This is followed by improving muscle strength around the knee. Finally, rehabilitation focuses on returning to preoperative activities, whether this is elite sport, fun sport or daily activities.

Did You Know

  • The stronger your thigh muscles are preoperatively the quicker and better your recovery will be.
  • The load distributed over the kneecap can be up to 5 times your body weight, particularly when squatting.
  • There are four bones in the knee, the femur, the tibia, the fibula and the patella.

Cartilage injuries

A common knee injury is a meniscal tear. The meniscus is the cartilage that is situated in the knee joint. Its purpose is to deepen the knee joint, allowing the femur (thigh bone) to sit more securely with the tibia (shin bone) which improves stability of the knee. We have a medial meniscus (inner side of knee) and a lateral meniscus (outer side of the knee).

A common mechanism of hurting the cartilage is twisting your knee, that is keeping your foot planted and twisting your body around. If you have torn the cartilage, there is often a lot of pain and swelling around the knee. Initial treatment should be RICE (rest, ice compression, elevation). Physiotherapy involves mobilising the joint, ensuring full range of movement and most importantly strengthening the muscles around the knee. In most cases cartilage injuries resolve in about 6 weeks. If symptoms persist and there is a significant reduction in the range of movement of the knee imaging may be required and possible surgery.


Osteoarthritis is a progressive joint disorder that causes wear and tear of the cartilage and bone of the joint. This often leads to bony spurs and changes in the joint surfaces.

These changes may cause significant pain and reduction in range of movement or may have no overt symptoms. Often changes seen on imaging such as, X-rays or MRIs do not correlate to symptoms people have. This has been shown in many research studies. Therefore, it is more important to concentrate on symptoms people have rather than what X-rays or MRIs show.

People often say to me, I have osteoarthritis in my knee and there’s nothing you can do for arthritis. Yes and no. No there is no cure for arthritis but there is lots that can be done for arthritis. Often with arthritis there is pain and when there is pain there is often muscle weakness. This leads to greater instability around the joint causing greater pain. Often there is joint stiffness due to the inflammation and swelling. These can be addressed by moving and stretching the joint or mobilising the joint which often relieves the pain. Specific exercises that address the muscle weakness can also be done. Both of these techniques have been found to reduce pain, improve joint mobility strengthen the muscles around the joint allowing for greater activity to be done.

All of these exercises concentrate on strengthening the thigh muscles (quadriceps). They vary in degree of difficulty. None of the exercises should cause and long-lasting pain. If you have any questions about your knee pain and/or these exercises, make an appointment with our physios and let them have a look.

Posted in

Lena Juross

Leave a Comment