Meniscal ossicle: posttraumatic origin and association with posterior meniscal root tears.

Objective: The purpose of this study was to characterize meniscal ossicles and their association with meniscal root tears.

Materials And Methods: A two-center retrospective assessment of 65 knee MRI studies with meniscal ossicles was performed. The relationship of the ossicle to the meniscal root and horn was assessed along with other findings of internal derangement of the knee.

Results: Meniscal ossicles were identified in patients ranging from 23 to 80 years old. The ossicles were located within the posterior horn and root of the medial meniscus in 57 of 65 (88%) examinations. Associated meniscal tears were seen at the site or adjacent to the ossicle in all but one examination (98%). Meniscal extrusion was present in 52% (34/65) of examinations. Associated findings included articular cartilage loss, which was severe in 51% (33/65) of examinations. Anterior cruciate ligament injury or prior anterior cruciate ligament reconstruction surgery was also identified in 58% (38/65) of examinations.

Conclusion: Our findings show that the vast majority of meniscal ossicles are associated with posterior horn or meniscal root tears and a high incidence of focal articular cartilage loss as well as anterior cruciate ligament tears.