Patellofemoral arthritis is generally characterized by pain at the articular surface of the patella, limitation of movement, and changes in the synovial fluid inside the joint. Patellofemoral arthritis is a kind of arthritis formed between patella and femur, when the patella is tilted laterally or semi-dislocated, resulting in the lateral condyle of femur sliding car being affected, excessive wear and tear of cartilage in the lateral joint space, which in turn produces a series of lesions of narrowing of the joint space, which is most often caused by the bones of the knee joint experiencing aging, degeneration, and hyperplasia. Clinical manifestations of patellofemoral arthritis are generally pain at the articular surface of the patella, which is usually aggravated when the patella is moved and alleviated after resting, and localized swelling as well as limitation of activities may also occur. Pain around the knee joint and changes in synovial fluid within the joint may also be present. Most patients may have a decrease in synovial fluid, i.e., the joint space is concave, and there is obvious friction during movement, as well as obvious bulging of the joint space. Treatment is generally feasible by puncture of the joint cavity and injection of chondro-nutritive lubricant, such as sodium vitrate injection, or by patellar osteotomy as well as replacement surgery of the chondral surface of the patella. If there is any of the above manifestations, it should be taken seriously and timely medical treatment is recommended.