Symptoms of advanced chondromalacia patella may include patellar rim pain, swelling, weakness and tenderness of both knees, and limitation of activities. 1. Patellofemoral rim pain: when the knee joint is active, squeezing or pushing the patella will have a friction feeling, accompanied by pain. Sitting for a long time will also cause pain in the knee, and the pain will be aggravated by going up and down stairs, kneeling or squatting, and often feel stiffness in the knee joint. 2. Swelling: in the advanced stage of chondromalacia patella, there are often symptoms of diffuse swelling around the joint. 3. Knee weakness: In the advanced stage of chondromalacia patella, the muscle strength decreases, resulting in knee weakness. Due to the pain caused by one side of the muscle wasting muscle atrophy, clearly seen on one side of the lower limb compared to the other side of the lower limb of the thin situation. 4. Restriction of activities: it is often manifested as weakness of legs, especially when going up and down the stairs, often due to the weakness of legs and suddenly fall down, so that the normal activities are restricted. When chondromalacia patella occurs, you should consult the doctor in time and follow the doctor’s instructions to avoid delaying the condition.