Study to Prevent Cartilage Damage Following Acute Knee Injury.

Individuals who have had a severe knee injury have an increased risk of developing arthritis of the knee and at a much earlier age than would otherwise be expected. The swelling and inflammation that occur after injury are believed to be responsible for this cartilage damage. The cartilage (material that provides a cushion in the knee) is the primary protection from what is called degenerative arthritis or osteoarthritis. We hope to reduce this swelling and prevent the damage to cartilage that occurs after injury by injecting a medication that blocks one of the proteins responsible for inflammation and cartilage breakdown. This protein is called interleukin-1 and can be inhibited by an interleukin-1 receptor antagonist called anakinra. Anakinra will be injected directly into the injured knee and response to the injection will be measured by symptoms and analysis of cartilage breakdown in the knee fluid and blood.