loosebody

A loose body is a free fragment found within a joint or another body cavity, not attached to surrounding tissue. In musculoskeletal contexts, loose bodies are usually composed of cartilage, bone, or degenerative material and can arise from trauma, degenerative joint disease, or displacing osteochondral fragments. They may also result from conditions such as synovial chondromatosis, where multiple cartilaginous nodules become loose, or from osteochondritis dissecans, when a fragment of bone and cartilage detaches.

In joints, the knee is the most commonly affected site, but loose bodies can occur in the hip, ankle, elbow, or shoulder. Symptoms vary and often include mechanical complaints such as locking, catching, grinding, or intermittent joint swelling. Pain and reduced range of motion may accompany these signs, though some loose bodies are asymptomatic and discovered incidentally on imaging.

Diagnosis typically begins with a clinical assessment followed by imaging. Plain radiographs can reveal calcified fragments, while computed tomography provides detailed visualization of bony components. Magnetic resonance imaging is useful for assessing noncalcified or cartilaginous fragments and associated soft-tissue pathology. In some cases, arthroscopy or diagnostic joint aspiration aids both diagnosis and treatment planning.

Management is guided by symptoms and underlying pathology. Asymptomatic loose bodies may be observed, while symptomatic or mechanically obstructive fragments are often removed surgically, commonly via arthroscopy. Addressing the underlying condition, such as osteoarthritis, meniscal tears, or synovial chondromatosis, is important to prevent recurrence or continued fragment formation. Prognosis after removal is generally favorable, though recurrence can occur if the source condition persists.