When the cartilage that typically covers the bone ends in the joint can no longer protect the bones, they can rub together, causing pain. While most common in the knee (see chondromalacia patella), chondromalacia can occur in any joint. Chondromalacia often begins as a soft spot in the cartilage, but the cartilage continues to soften until it becomes cracked or shredded–or in severe cases, worn away completely. Pieces of the worn cartilage can float within the joint causing irritation in the joint lining. This irritation can cause the cells within the joint to produce fluid, known as joint effusion. There are many situations and conditions that can lead to chondromalacia, including overuse, muscle imbalance, rheumatoid arthritis, osteoarthritis, repeated episodes of bleeding in the joint, and repeated steroid injections into the joint. Because the type of cartilage that protects the joints (articular cartilage) heals poorly, chondromalacia can be a permanent condition. There are non-surgical treatment options, though, that can alleviate pain within a few months. These treatments include applying ice; taking a nonsteroidal anti-inflammatory and pain-relieving medication (e.g., ibuprofen); starting a low-impact exercise program to strengthen the muscles around the joint; and wearing a brace or using tape to keep the joint aligned. If non-surgical treatments are not effective, surgery to remove the damaged cartilage may be necessary.