Meniscal ossicle.

Meniscal ossicles are rare and may cause diagnostic difficulty on plain radiograph at presentation. Magnetic resonance imaging is useful in detecting meniscal ossicles because their characteristic appearance on MRI can differentiate them from other disease. Arthroscopy can also diagnose the meniscal ossicle, which in our patient appeared as a swelling in the meniscus. If the patient is asymptomatic before the time of diagnosis, removal of the ossicle may not be indicated and, as with our patient, normal function is possible with the ossicle retained.