With the knee comprising of two of the longest bones in the body, it is therefore the furthest joint away from any other joint in the body. It could be then argued that it is the most vulnerable joint in the body. That certainly runs true with the majority of people seen in clinic. The knee joint is completely reliant on the hip and ankle's ability to their job well. If there is a problem in either of these two areas, it is highly likely the knee will be subjected to more stress than it would like. The majority of knee pain we see here is because of this reason. Therefore, most people don't have an actual injury or a history of trauma, they just report pain. Once we work out why the knee is suffering, then we can direct treatment to the most appropriate place.
Now not all knee pain is due to biomechanical factors, and we do see actual knee injuries. Outlined below are some of the more common ones we see.
Ligament sprains / cartilage tears
There are several ligaments that are integral to the knee joint. The more common ones to injure are the medial collateral ligament (MCL) or the anterior cruciate ligament (ACL). The MCL is found on the inside of the joint and the ACL is located deep within it. Both can be injured due to force being applied to the outside of the knee, excessive twisting/rotational movements, landing from a jump or as a result of a sudden change in direction.
The thick cartilage found in the knee is known as the meniscus. Injuries to the meniscus also commonly occur with the movements describe above. There is often swelling, locking of the knee, pain in the knee when going up or down stairs and also pain with walking.
Most MCL ligament sprains respond extremely well with physical therapy treatment. Tears to the meniscus, and or ACL, often require surgery to repair them. A thorough assessment will reveal which structures are damaged and then the appropriate route can be decided.
With any knee injury, it is important to assess how the joints above and below are moving. Even if surgery is required, it is important that the knee be fully taught how to move again properly. It needs to be able to not only move on it's own, but in harmony with the foot, hip, pelvis and even the other leg and rest of the body.