Osteoarthritis affected 2.2 million Australians during 2017-18 and is the most common form of arthritis found today. This prevalence increases with age; found within 1 in 5 over 45 years old, and 1 in 3 over 75 years old (AIHW, 2023).
In fact, Australia spends more than $1.4 billion per year on knee replacements for osteoarthritis patients (Arthritis Australia, 2022). But despite all this, knee osteoarthritis does not have to be the massive burden it’s made out to be.
The knee joint & it’s cartilage:
The knee is made up of two bones: the femur (thigh bone) and the tibia (shin bone) and it is primarily moved by two main muscle groups in your thigh – the quadriceps on top of your thigh work to straighten the knee, while the hamstrings on the back of your thigh work to bend your knee. Inside the knee joint itself, you have several ligaments that aim to connect all the bone together and make sure the knee doesn’t give way when you’re moving. Sitting atop the bone itself lies the cartilage which lines the heads of the two bones. This articular cartilage aims to protect the bones when they rub against each other during movement, ensuring that the movement is smooth, frictionless, and gentle.
What happens to the cartilage in OA?
During OA the cartilage which lines your knees begins to degrade, where the regeneration of cartilage does not balance the degeneration, reducing the ability of the cartilage to provide that smooth cushioned surface. This can lead to painful, stiff movements as well as swelling within the knee. Due to the chronic inflammatory nature of OA, it’s unlikely that cartilage in the knee will heal itself and thus most changes will be permanent.
OA is a disease that affects the whole joint not just the cartilage.
What we do however know is that there are several risk factors for cartilage degradation which include:
· Traumatic injury to the knee
· Long term knee overuse
· Obesity
· Poor activity levels
Research has also suggested the following:
· Age: OA risk increases with age
· Sex: Women are more likely to be diagnosed
· Genetics: Family history of OA or OA in another body part increases risk of knee OA
What does having OA feel like?
Symptoms develop slowly and vary;
pain on weight bearing
stiffness with prolonged rest
activity limitations
reduced participation in activities
How can we treat this?
When approaching management of knee OA – it’s important to first address some common views on the condition. Firstly, it’s important to note that whilst many people may have OA-related changes in their knees – only some will exhibit pain. This suggests that OA related changes in the knee may not be a source of pain, but a source of changing sensitivity to pain in the knee.
It is also important to note that pain does also not mean that you doing more damage.
The first line of treatment for knee OA is education , exercise and weight control. Our physiotherapists will work with you to design an evidenced based treatment program that includes a strengthening program for the muscles that support the knee, stretches to help improve range of motion and advice on how to lose weight and stay healthier.
In some cases, the degradation in the joint becomes too much and pain and function are unable to be adequately controlled by conservative therapy. At this point, knee joint replacement surgery is considered the likely treatment option. During this, the joint surfaces of the femur and the tibia are replaced and a spacer placed between them. As the new components replace the degenerative joint, the surgery can provide significant relief and can often last for a period of 15-20 years.
Comments