Symptoms of patellofemoral osteoarthritis mainly manifest as pain, morning stiffness, bone friction sound and so on. 1. Pain: at the early stage of the disease, the pain is mild and dull, generally aggravated after activity and alleviated after rest. The degree of pain is related to the degree of exertion, weather changes, cold and dampness and other factors. After the joints are damaged, it may also show as resting pain, which will be relieved after activities. 2. Morning stiffness: mostly manifested as stiffness in the joints when waking up in the morning, which is relieved after activities and usually lasts for less than half an hour. 3. Bone friction sound: generally appear in the late stage of patellofemoral arthritis, the patella joint surface is not flat, so the joint activities will appear bone friction sound. If you suspect patellofemoral osteoarthritis, you should consult a doctor in time and follow the doctor’s requirements for treatment.