Chondromalacia patellae is damage to the patella cartilage. It is like a softening or wear and tear of the cartilage.The roughening or damage can range from slight to severe.
Chondromalacia patellae occurs most often in young adults and teenagers. It is more common in women. The reason why damage occurs to the cartilage is not clear. It is thought that the patella may rub against the lower part of the thigh bone (femur) instead of gliding smoothly over it. This may damage the patellar cartilage. Situations where this is more likely include the following:
• Overuse of the knee, such as in certain sports.
• Some people may have a slight problem in the alignment of the knee. This may cause the patella to rub on, rather than glide over, the lower femur. It may be due to the way the knee has developed. Or, it may be due to an imbalance in the muscles around the knee – for example, the large quadriceps muscle above the knee. If one side of the quadriceps muscles pulls harder than the other side, then the patella may not glide true and may rub on one side.
• A combination of an alignment problem (as above) and overuse with sports, may be the most common reason for getting chondromalacia patellae.
• Injury to the knee may contribute – perhaps repeated small injuries or stresses due to sports, or due to slack ligaments (hypermobile joints).
• In older people it may develop as part of the ageing process where there is wear and tear of cartilage in many joints.
Patients who suffer from this condition will suffer from the following symptoms:
• Pain around the knee. The pain is usually located at the front of the knee, around or behind the kneecap. The pain is typically worse when going up or down stairs. It may be brought on by sitting (with the knees bent) for long periods.
• A grating or grinding feeling or noise when the knee moves (crepitus).
• Rarely, some fluid swelling (effusion) of the knee joint.
• Avoid strenuous use of the knee – until the pain eases. Symptoms usually improve in time if the knee is not overused.
• Painkillers – paracetamol or anti-inflammatory painkillers such as ibuprofen may be advised to ease the pain.
• Physiotherapy – improving the strength of the muscles around the knee will ease the stress on the knee. Also, specific exercises may help to correct problems with alignment and muscle balance around the knee. For example, you may be taught to do exercises which strengthen the inner side of the quadriceps muscle.
• Taping of the patella – is a possible treatment which can reduce pain. Adhesive tape is applied over the patella, to alter the alignment or the way the patella moves. Some people find this helpful. Some physiotherapists can offer patellar taping treatment.
Surgery is not usually necessary, but may be advised if the above treatments have not helped. Arthroscopic surgery is the usual operation. A tiny flexible camera is inserted into the knee. The surgeon sees the inside of the knee joint and the cartilage, and may then operate through the camera tube, using very fine instruments. Possible surgical treatments are as follows:
• Tight ligaments on the side of the patella may be cut to allow the patella to align better and move more smoothly.
• Smoothing or shaving the cartilage behind the patella.
• Rarely, if all other options do not help, the patella can be removed (the knee can still function without it).