The bone that protrudes from the front of the knee is called the patella and is an important part of the knee joint and an important structure of the knee. The patella is very important for the knee joint and can strengthen the quadriceps muscle, which can protect the knee joint. Diseases that cause patellar injury in the clinic are usually patellar fracture, patellar dislocation and chondromalacia patella, all of which can lead to physiological changes in the patella, causing traumatic arthritis and osteoarthritis. Patellar fracture is a more common disease, patellar fracture needs to be given timely treatment, and in a period of time to make the fracture to achieve anatomical restoration, to prevent the occurrence of later osteoarthritis. After the patella fracture, we should actively carry out functional exercise to prevent muscle atrophy and joint ankylosis.