Filling Potholes along the Knee Cartilage Highway

Joint cartilage, the smooth lining that covers joints, doesn't register pain. But when cartilage in the knee joint is damaged, it can put painful pressure on the bone below (called subchondral bone). This can cause painful swelling.

It's not easy to repair joint cartilage. Patients often lose joint function. Osteoarthritis and disability can be the end result of this condition. New methods of regaining or restoring knee cartilage are being studied.

Doctors in Sweden and Norway combined efforts to describe damage to the knee joint. They did this by filling out a form after every surgery done with an arthroscope. The arthroscope is a slender device with a tiny TV camera on the end. It can be inserted into the joint so the doctor can look inside.

One thousand knees were examined this way. The location, size, and depth of the damage were recorded. Doctors also measured knee motion, swelling, and other areas of damage or disease. The hope is to find out which patients should have surgery to repair the damaged cartilage.

Defects in the joint knee cartilage are common. Some are caused by trauma and injury. Others occur after years of wear and tear. Younger patients tend to have moderate-sized areas of damage. Larger defects come from repeated minor injuries to the joint surface, along with the effects of aging.

Smaller areas of damage respond better to treatment. Patients younger than 45 years have the best results with surgery. The upper limit of age for a successful operation seems to be around 50 years. Results are best in all ages if the repair is made within three weeks of injury.



References: Karin Hjelle, MD, et al. Articular Cartilage Defects in 1,000 Knee Arthroscopies. In Arthroscopy. September 2002. Vol. 18. No. 7. Pp. 730-734.