Foot joint crunching may be caused by physiologic popping, osteoarthritis, ankle injury and other factors. 1. Physiological rattling: when normal joints are in motion, the cartilage pads and joint surfaces will rub against each other, resulting in physiological rattling, which is a normal phenomenon and is usually not accompanied by other discomforts. 2. Osteoarthritis: the cause of osteoarthritis is related to age, obesity, inflammation, trauma and other factors. Inflammation can cause damage to the articular cartilage, the joint surface is uneven, so the joints will be rubbed when the joints are moving, and the symptom of crunching occurs. 3. Ankle joint injury: due to trauma, chronic strain and other reasons can cause joint ligament, cartilage and even bone damage, resulting in the destruction of the ankle joint and instability, in the activities, the joint friction, thus appearing foot joints crunching, accompanied by local pain. For normal physiological phenomena do not need special treatment, if accompanied by symptoms of discomfort, should promptly consult a doctor for examination, to clarify the cause of the disease for targeted treatment.