Showing chondromalacia

Although symptoms may not appear until later in life, articular cartilage problems are very common. Painful osteoarthritis develops when this smooth, gliding surface on the end of the bone has lost its cushioning, deformity develops, and bone rubs on bone. Damage may occur as the result of a sudden injury or wear and tear over many years. There are some people with damaged articular cartilage who display few symptoms and may not develop osteoarthritis until they are elderly.

The development of ostearthritis depends on several factors:

• The patient's age when the degeneration starts
• The patient's activity level and weight
• The presence of ligament damage

Articular cartilage problems can be particularly difficult to treat because the onset, while occasionally sudden, often occurs gradually and thus is not immediately detected.

What is articular cartilage and what does it do?

There are two types of cartilage in the human knee:

• Meniscus cartilage - This is the cartilage most commonly referred to when the term "torn cartilage" is used. These two rubbery shock absorbers sit between the upper bone of the thigh (femur) and the large bone in the lower leg (tibia).
• Articular cartilage - This cartilage is the shiny, white surface that covers the ends of most bones. Articular cartilage protects the ends of bones and allows the joints to glide smoothly with less friction. It also helps to spread the loads applied to a joint. This covering is only a few millimeters thick and it has no blood supply to facilitate the healing process. Therefore, if it gets damaged, there is very little capacity for healing.

What is an articular cartilage injury?

An articular cartilage injury, or chondral injury, may occur as a result of a pivot or twist on a bent knee, similar to the motion that can cause a meniscus tear. Damage may also be the result of a direct blow to the knee. Chondral injuries may accompany an injury to a ligament, such as the anterior cruciate ligament. Small pieces of the articular cartilage can actually break off and float around in the knee as loose bodies, causing locking, catching, and/or swelling. More often, there is no clear history of a single injury. The patient's condition may, in fact, result from a series of minor injuries that have occurred over time. Articular cartilage also wears down as a person ages.

• Grade I - The cartilage "blisters" and becomes soft in the earliest form of damage.
• Grade II and III - As the condition worsens, the cartilage may become fibrillated (it has a shredded appearance). The grade of injury depends on the size of the involved area and how much of the cartilage thickness is worn down. Noise as the knee bends, called crepitus, may be present.
• Grade IV - The cartilage may wear away completely, leaving the underlying bone exposed in small or widespread areas. When the involved areas are large, pain usually becomes more severe, causing a limitation in activity.