Intra-articular loose bodies can result from a variety of pathological processes.
Use of the term "loose" is frowned upon by some because the fragments do not necessarily move around in the joint - the term intra-articular body or fragment is a safer alternative.
Patients may be entirely asymptomatic or complain of pain, clicking and locking, depending on the location and mobility of the fragment as well as any associated secondary degenerative disease, and symptoms from the underlying cause.
Intra-articular bodies are composed of cartilage or cartilage and bone and result from any process that leads to disruption of the articular surface. They derive nutrition from synovial fluid and contain any of the cells of bone or cartilage. The surface cells form more cartilaginous layers, so enlarging the body over time. Deeper cells receive less nutrition resulting in cell death and calcification 2.
A wide range of conditions can lead to the development of intra-articular loose bodies:
- 1. Resnick D, Kransdorf MJ. Bone and joint imaging. W B Saunders Co. (2005) ISBN:0721602703. Read it at Google Books - Find it at Amazon
- 2. Milgram, James W; Gilden, Jerome J; Gilula, Louis A. Multiple Loose Bodies: Formation, Revascularization, and Resorption A 29-Year Followup Study.[Article] Source Clinical Orthopaedics & Related Research. 322:152-157, January 1996.
- 3. Dähnert W. Radiology Review Manual. LWW. (2011) ISBN:1609139437. Read it at Google Books - Find it at Amazon
- 4. Bianchi S, Martinoli C. Detection of loose bodies in joints. (1999) Radiologic clinics of North America. 37 (4): 679-90. Pubmed