Injuries and Displacements of the Semilunar Cartilages.

Rotation strain, caused by twisting of the knee. If weight is being borne on the flexed knee with the foot firmly anchored to the ground, the force of the injury in addition to stretching or tearing the coronary ligaments may cause a split or fracture of the semilunar cartilage. When no weight is borne, or if the foot be not held, the semilunar may escape. The modern football boot, with good studs to prevent slipping, often gives just that fixation which causes damage to the cartilages, whereas a rotation sprain whilst on a pair of skis, by allowing the foot to slip, more often causes tearing of the ligaments and allows the cartilage to escape.