Loose Bodies in the Knee
What are loose bodies in the knee?
A loose body is a fragment of cartilage or bone that has broken away from a surface of bone in the knee. Loose bodies may be stable (in situ) and remain in place or unstable “loose” and float freely in the thick synovial fluid that protects and lubricates our joints. They can cause pain, swelling, and inflammation and make it difficult to move the knee. A loose body may also cause damage to the inside of the knee joint and the articular cartilage leading to the development of early osteoarthritis.
What causes loose bodies in the knee?
There are a few things that can cause loose bodies in the knee:
- Trauma: A direct impact to the knee that causes a cartilage defect can create loose bodies.
- Patellar instability: This is a condition caused by dislocation of the kneecap or patella. It is caused by trauma and damages the articular cartilage producing loose bodies.
- Degenerative joint disease (Osteoarthritis): This is a condition that occurs when the cartilage in the joints breaks down from wear and tear. It can cause small pieces of cartilage to break off and float around in the joint space.
- Osteochondritis dissecans: This is a condition that affects the bone and cartilage. It can cause small pieces of cartilage or bone to break off and float around in the joint space.
What are the symptoms of loose bodies?
Stable loose bodies are in a fixed position and may not cause symptoms. Unstable loose bodies get trapped in the joint and cause pain, clicking and sporadic knee locking, swelling, and stiffness. Loose bodies can be microscopic but can get bigger as new cells develop on the fragment surface, or if it calcifies or ossifies. They can grow quite substantially, even up to the size of a golf ball.
How are loose bodies in the knee diagnosed?
Dr. Harrison will ask about your symptoms, knee injuries, and medical history. He will also perform a physical exam testing range of motion and knee stability. He may order imaging studies, such as an X-ray, CT scan, or MRI to evaluate the bones and soft tissues. These tests can help Dr. Harrison see the loose bodies, rule out other medical conditions and identify the cause of the loose bodies.
How are loose bodies in the knee treated?
Loose bodies in the knee usually aren’t a problem until they start causing irritating symptoms. The most obvious symptom is pain but the knee may swell or have inflammation. If you do have symptoms, treatment options include:
- Nonoperative treatment: Physical therapy, steroid injections, hyaluronic acid injections, anti-inflammatory medications, activity modification and weight loss can help to treat pain and swelling when the loose bodies are not cause mechanical locking.
- Surgery: Minimally invasive arthroscopic debridement is the standard surgical procedure to remove loose bodies in the knee. The advantages are minimal incisions, less scarring and fewer complications than open procedures. It is especially helpful to treat loose bodies from arthritis of the knee that are causing pain and impairing function.
Call Dr. Harrison to schedule a knee consultation.
Dr. Harrison is a board-certified fellowship trained orthopedic and sports medicine surgeon who specializes in arthroscopic knee and shoulder surgery. He is the Head Team Physician for the United States Alpine Ski Team and the Head Team Physician for Weber State University for over 20 years. Dr. Harrison completed his undergraduate degree at Baylor University and received his medical degree from the University of Arizona College of Medicine. He completed his orthopedic residency at the University of Utah followed by a fellowship in sports medicine at the Cincinnati Sports Medicine and Orthopedic Center. He finished his formal training with an additional AO Trauma Fellowship in Bern, Switzerland.
At a Glance
Dr. Jeffrey Harrison
- Board-Certified, Fellowship-Trained Orthopedic Surgeon
- Head Team Physician US Women's Alpine Team and Weber State University
- Performs over 800 surgeries per year
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