1.An 18-year-old boy was hit down by car while walking on the road and sustained injury to his right knee joint. He visited to orthopaedic clinic with complaints of pain, swelling and while walking his right knee is giving out (instability). On examination, soft tissue swelling and tenderness present around right knee joint. Lachman test was performed and shows abnormal forward & backward movement of right tibia. With your anatomical knowledge answer the following questions related to knee joint. Describe the articular surfaces of knee joint. Describe the ligaments of knee joint. Name the structure(s) that maintain the anteroposterior stability of knee joint. What is locking and unlocking of knee joint. Nerves that supply knee joint