Patient: Patient is male, 23 years old, previously in good physical condition. This time: left knee joint can’t make strength; no pain when walking, everything is normal; pain when squatting, slight pain when going up stairs and riding bicycle, symptoms have appeared for 4 months. MR scan results: the bones of the left knee joint were well combined, and a faint lamellar long T2 signal shadow was seen in the left patella, the border was not clear, and the local bone cortex was still continuous; the rest of the bones of the left knee joint were continuous, the edges were bright, and no abnormal signal shadow was seen in all sequences; the morphology of the left knee medial and lateral meniscus was as normal; the anterior and posterior cruciate ligaments, medial and lateral collateral ligaments and patellar ligaments of the left knee were continuous, and no abnormal signal was seen in all sequences. A small amount of fluid was seen in the left knee joint cavity and synovial bursa. Diagnosis and recommendation: left patellar lamellar long T2 signal, suggesting bone injury; small amount of effusion in the left knee joint cavity and synovial bursa. I have never been treated, but my doctor recommends daily care. How should I treat or care for it? Yuan Yi, Department of Orthopedics, Ningbo Second Hospital: The symptoms described suggest that the injury is in the patellofemoral joint, so the pain is worse when going up and down stairs, riding a bicycle and squatting, but there is no significant discomfort when walking normally. The imaging data is consistent with the above symptoms. A small amount of effusion should be reactive. The long T2 signal is mostly water signal. Therefore, the injury can be determined. No other structures were found to be significantly abnormal. In combination with the age, we consider conservative treatment with chondroitin sulfate and glucosamine drugs, which have the ability to promote cartilage repair. Daily life to reduce semi-squatting and weight-bearing knee flexion and other movements, can do quadriceps training.