M22.4: Chondromalacia patellae
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.
The kneecap is embedded in a tendon of a muscle. This muscle pulls from the thighbone and from the hip to the shinbone and extends the knee. The kneecap helps this muscle to transfer force more effectively. The kneecap also reduces the friction between the tendon and the thighbone.
The cartilage on the kneecap can be damaged if the kneecap comes under too much strain. The cartilage may also get damaged if the position of the kneecap in the groove of the bone changes.
The cartilage damage can cause pain in the knee, for example when you straighten up from squatting. The knee may also be swollen.
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For a complete understanding of your condition and what the diagnosis means for you, please speak directly with your doctor.