If the knee joint feels like something is stuck, there may be a free body in the knee joint or a meniscus injury with strangulation. You can go to the orthopedic department to see a doctor, who will make a preliminary judgment based on the physical examination, and can improve the X-ray examination of the knee joint to understand whether there is any obvious free body in the knee joint. If a meniscal injury is considered after the examination, an MRI of the knee joint can be done to help determine the exact diagnosis, and the corresponding treatment can be done according to the results of the examination. If the meniscus injury is not serious, you can try conservative treatment first. Pay attention to rest and avoid excessive knee flexion, in addition, you can spray local aerosol for swelling and pain. For more serious meniscus injury or free body, arthroscopic surgery can be performed.