How it works - The Knee

Anatomy

The knee joint is made up of three bones and is the articulation of the tibia, femur and patella. Probably the most fascinating part of the knee joint is the patella, the largest sesamoid bone in the body. A sesamoid bone is a bone which has a tendon embedded or pass through it. In the Patella’s case, the patella tendon does pass through this bone, providing muscular attachment of the quadriceps muscles to the shin bone

Structurally the knee is supported by four ligaments. On the medial (inside) of the knee is the Medial Collateral ligament and conversely on the lateral (outside) of the knee is the Lateral Collateral ligament. These two ligament provide support for stress through the medial and lateral joint lines. Inside the knee joint lie the two cruciate ligaments. The Anterior Cruciate Ligament prevents the tibia coming forward on the femur whilst the Posterior Cruciate Ligament prevents the tibia sliding backwards on the femur.

Function

Unlike the complexity of the ankle, the knee joint is a fairly straight forward hinge joint. This means that the motions of the knee are flexion (bending) and extension (straightening).

The knee, like the ankle is a critical element of the gait cycle. It bends during the swing phase to allow the foot to clear the ground and therefore not drag on the ground. After the swing phase the leg extends to support the weight of the body in the stance phase. As well as its functions in gait, the knee is a powerful lever for activity of the quads.

Common injuries

In terms of injuries at the knee, there are a lot of different mechanisms and modes of injury. For the purpose of this introduction to the knee we will break these into overuse and acute/traumatic injuries. Overuse injuries are those that happen over time with no specific cause. These are generally due to poor biomechanics or control around the hip as well as excessive loading with insufficient rest. Examples of these injuries are patella tendinitis, patellofemoral tracking problems and fat pad impingement of the knee. These non-traumatic normally require some rest or load modification and respond really well to hands on Physiotherapy and guided exercise rehabilitation.

On the other hand, the traumatic injuries obviously occur with a clear mechanical incident. In the majority of these cases surgery or a period of immobilisation is required, depending on the type and extent of the injury. The key component of our diagnosis of these traumatic injuries is understanding the exact mechanism of the injury. Our Physiotherapists are experts in clinical reasoning and fully understand when we need to refer on for medical imaging as well as orthopaedic specialists.

If you have any knee complaints that aren’t listed in this article, why not come in and see one of our Friendly Physiotherapist’s today. We think you kneed too