Jacky Peter Physiotherapy - Physio FAQ's (Knee)

I have pain behind my knee cap, what is this? >>back to top: The most common cause of pain behind the knee cap is a because the knee cap (patella) is not 'tracking' properly. It most often is being pulled to the outside of the leg by tightness in the outer thigh muscles. The inner thigh muscle (vastus medialis) is weak while the outer one is too strong. This causes pain in the knee as the cartilage gets worn out unevenly. Relief is most often easily achieved by releasing/stretching the outer thigh muscles and strengthening the inner ones.
I have damaged my cartilage, what is this and can physio help? >>back to top: Cartilage is what lines the surfaces of a joint. It is often smooth to assist the joints to glide easily during movements. Sometimes it is rough to assist in making a joint more stable (like the pelvis).

In the knee, cartilage lines the femur (thigh bone), tibia (shin bone) and patella (knee cap). Therefore cartilage damage can happen in any one of these areas, often due to uneven wear and tear, and a sports injury.
Damaged cartilage does not regenerate/heal itself very well however, physiotherapy is crucial to correct the reasons for the damage being caused in the first place. For example, a muscle imbalance around the knee cap will cause the cartilage of the knee cap to wear out more on the one side than the other. Correcting the muscle imbalance will cause normal distribution of forces on the cartilage and can take the pressure off of the damaged area.
Just how crucial are the "cruciate" ligaments to the knee? >>back to top: These ligaments are vital to the stability of the knee! The ACL (anterior cruciate ligament) and PCL (posterior cruciate ligament) prevent too much movement of the tibia (shin bone) on the femur (thigh bone). This movement occurs with normal walking, but more so with sporting activities (especially ones where you pivot on the leg like netball, hockey, squash, soccer). Damage to these ligaments will result in excessive movement in the joint which will also put stress on the cartilage, meniscus and medial/lateral collateral ligaments of the knee.
Which sports are considered knee friendly? >>back to top: Swimming and cycling the the best as there is less pressure on the knees.
Squash, hockey and running are considered high risk for knee injuries.

However, not everyone fits into little boxes. For example, someone who has an injury to their ACL (anterior cruciate ligament) of the knee should not do sports that cause rotation at the knee like hockey/squash. However, running is much less rotational stress on the knee and may be OK, depending on how badly the ligament is damaged etc.
Will a brace or knee guard help/protect my knee completely? >>back to top: No, a knee guard will not be enough to protect or support your knee. Most guards that you can get from the shops will only give you awareness of what your knee is doing (called proprioception). This is good though, because it is important for your knee to get that type of input to prevent an awkward movement. However, it will not really offer much support to the ligaments because a piece of material is by no means strong enough to shield forces transmitted to the knee.
Although these guards are not all you need to protect/support your knee, they are very helpful as an addition to your rehabilitation!

A brace is a much stronger type of support than a knee guard. Thin pieces of metal in strategic points help prevent a ligament from overstretching/tearing. These are often custom made for a person's specific type of injury and body shape. Similarly though, this is not the be all of your rehabilitation! Specific muscles still need to be strengthened, mechanics of movement corrected, balance and core need to be retrained etc.
My child has knee pain, what could this be? >>back to top: Children under 15 years may develop knee pain for various reasons. One common reason is: The front thigh muscle called 'quadriceps' attaches to the kneecap, which attaches to the top of the shinbone. During childhood, the growth plates (which are at the end of a bone) have not yet fully closed and are at risk of injury. So the thigh muscle pulls on the bone where the bone is still growing and causes pain and swelling at the bottom of the kneecap.

This is more common in boys than girls. This injury is initially treated with rest (no excessive sports) and ice. When the pain becomes less, the thigh muscle needs to be stretched to take the pressure off the kneecap and bone.