Unhappy triad posterior translation of the tibia on the femur. The classic O'Donoghue triad is characterized by an injury to three knee structures (in order): The anterior cruciate ligament is one of the four crucial ligaments in the knee. It originates from the lateral condyle of the femur and goes to the intercondyloid eminence of the tibia. Its function is to provide stability in the knee and minimize stress across the knee joint. It also restrains excessive forward movement in the leg and limits rotational movements in the knee. Injury An anterior cruciate ligament injury results from excess tension on the ligament.
Triple tibial osteotomy tibia with respect to the femur, hyperextension of the stifle joint and internal rotation of the tibia. The cranial cruciate ligament is thought to be able to resist a force equivalent to four times the weight of the dog before it ruptures, but often the ligament is weakened by arthritis that is present in the joint. Arthritis infers inflammation of the joint; in this condition there is the production of a joint fluid that is less viscous and therefore less able to absorb shock than normal fluid. Joint fluid's other role is to provide nutrition to the cartilage and the