12.膝關節受傷扯斷脛側副韌帶（tibial collateral ligament），下列何者最可能同時受損？
(A)髕骨（patella）
(B)腓骨（fibula）
(C)內側關節盤（medial meniscus）
(D)外側關節盤（lateral meniscus）

The unhappy triad occurs due to a lateral blow to the knee causing a rupture in the anterior cruciate ligament, medial collateral ligament, and meniscus. Injury is most often sustained when a lateral (from the outside) force impacts the knee while the foot is fixed on the ground. The strong valgus or rotary force to the knee tears the ACL, MCL, and medial meniscus all together. This type of injury occurs often in contact sports such as football, rugby, or motocross. During the injury, the leg is laterally rotated and over-abducted. In about 10% of cases, the force is applied to the opposite side of the knee, and the lateral and posterolateral ligaments are torn. (WIKIPEDIA)