Medical Q&As

Chondromalacia patellae - what is it?

What is chondromalacia patellae?

The term chondromalacia means softening of cartilage and patellae refers to the knee cap. The back of the knee cap is covered with smooth shiny cartilage that glides over the lower end of the femur or thigh bone when the knee joint is being flexed or extended. If the cartilage softens it can fragment giving rise to inflammation at the back of the knee cap, which results in pain and reduction in the degree of movement in the knee joint. In severe cases the person may walk with a limp. It can affect middle-aged people where the fragmentation of the cartilage is simply part of a wear and tear process. However, it more commonly occurs in teenagers with females being more frequently affected. It is associated in this age group with excessive growth spurts and muscle imbalance around the knee. A teenage girl is more likely to develop the condition if she is tall or has a degree of knock-knee. Also, if she has tightness of the lateral muscles or muscles to the outside of the knee, she may be more prone to developing this problem. It is most frequently seen in those that are active in sports. The best way of preventing this condition is to warm up and perform stretching exercises before engaging in sports. It is also helpful if the person varies their sport. For example it is helpful to alternate running with swimming. If the condition has flared up it is best to avoid squatting, kneeling or running on uneven ground because these activities cause impact between the fragmented cartilage and the lower end of the femur. Antinflammatory medication can be helpful to relieve the pain and counteract the inflammation. Physiotherapy can also be helpful particularly with regard to advice and instruction about exercises that strengthen the muscles around the knee. It is necessary to be patient with this condition because it can take up to six weeks for it to subside. Chondromalacia patellae can recur and in that circumstance the relapse is likely to be due to lack of attention to warm up exercises and persistent tightness in the lateral muscles. In severe persistent cases it can progress on to the development of arthritis at the junction between the back of the knee cap and lower surface of the femur.