Figure 2.

Biomechanical function of the meniscus, where: (A) Axial compressive forces from the femur (F_femur) and tibia (F_tibia) during joint loading are converted into the circumferential “hoop” direction (F_circ) that are resisted by the tensile stiffness of the circumferential collagen fibers and are transferred into the horn attachments (F_att). (B) This load transfer reduces the axial forces on the underlying articular cartilage. (C) With a meniscus root avulsion or large-scale radial tear, the hoop stress is lost and the axial forces are applied directly to the cartilage, the clinical equivalent of a meniscectomy, and leads to cartilage osteoarthritis. (A) Courtesy from Dawn Elliott and Robert Mauck; (B) and (C): (Courtesy from Itthipanichpong et al. [18]).