Anatomy of the knee joint

The largest joint in the body – the knee – is the connection between the lower and upper thigh. It is composed of the lower end of the femur (thigh bone), the upper end of the tibia (shin bone) and the patella (kneecap). It is therefore an interaction of several partial joints.

Since the bone structures do not fit exactly into each other in terms of their shape, there are some auxiliary devices: e.g. the flat tibia plateau (upper end of the tibia). The round condyles of the thigh bone move on this plateau in a roll-slide motion. A common syndrome in runners that affects precisely these structures is patellar tip syndrome, also known as jumpers-knee.

On the back of the knee, in the hollow of the knee, the tendons of the rear thigh muscles, the so-called ischiocrural muscles or hamstrings, run from above, and the insertions of the calf muscles run from below. In order to prevent great friction between bones and tendons, various bursae are temporarily stored in these structures. Ligaments and joint capsules are responsible for the so-called passive stability in the knee joint.

In order to adapt the two shapes for optimal movement and to distribute loads evenly over the entire joint, there are two menisci in the knee joint.
To ensure stability, the anterior and posterior cruciate ligaments run through the middle of the knee. The names of these ligaments are derived from the fact that, when viewed from the front, they cross in the middle of the knee. They hold the two articulating bones together and prevent them from slipping forward or backward.
From the sides, the knee is held together by the collateral ligaments (collateral ligaments), which pull once each right and left across the joint gap.
The largest and strongest ligament (thigh tendon and patella tendon) runs flat over the kneecap at the front. Coming from the strong quadriceps femoris muscle, it fixes the kneecap to the anterior knee joint, presses it against the thigh and then attaches to the tibia below the knee joint.