5-804.1:

You have had an operation on one or more of the knee ligaments that are meant to hold your kneecap in the right position.

The knee joint connects the thigh to the lower leg. The knee joint is made up of 3 bones. These bones are the thighbone (femur), the shinbone (tibia) and the kneecap. The kneecap sits in a groove at the front of the thighbone. Tendons are made up of very firm connective tissue. Tendons attach muscles to bones.

There is a large muscle at the front of the thigh. There are different parts to the muscle, including a part on the inside of the leg and one on the outside of the leg. The inside of the leg is the side that points towards the other leg. The tendons from the different parts of the muscle are principally attached to the kneecap. The patellar tendon then runs from the kneecap to the tibia.

Various ligaments made out of connective tissue help to keep the kneecap in the right position centrally at the front of the femur. There is a retinaculum running on each side of the leg, inside and out, from the kneecap to the shinbone. The retinacula consist of various connective tissue fibers, such as tendon fibers in muscles.

The retinaculum of your kneecap on the outside of your leg has been severed. The operation can involve gathering the retinaculum on the inside of the leg, or connecting it to the one on the outside.

You also had surgery on a tendon in the large muscle in your thigh. The surgery was carried out on the part of the muscle that is on the inside of the leg. Some of your tendon fibers are usually attached at the top of the inside of your knee. The operation involved cutting through these tendon fibers and attaching them further down and more to the outside of your kneecap.

The operation should result in your kneecap sitting in the middle at the front of your femur.