Leg joints crunching when you move may be related to physiological factors, osteoarthritis of the knee, ligament damage, meniscus injury and other reasons. 1. Physiological factors: if the leg joints crunch when you move without any pain, it is mostly considered as physiological popping, which may be related to the gas extrusion in the joints, and it will not affect your health, so no special intervention is needed. 2. Osteoarthritis of the knee: it is usually caused by bone proliferation and degeneration in the joints of the leg, and is mostly seen in the elderly. Osteoarthritis can lead to narrowing of the joint space. When these patients move their joints, the cartilage rubs against each other, causing the leg joints to creak when they move. 3. Ligament and meniscus injuries: When the patient suffers trauma to the leg joints, if it leads to joint ligament and meniscus injuries, the ligament rupture causes abnormal structural position, abnormal friction or meniscus friction, which leads to leg joints rattling when moving. If accompanied by other discomforts, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give standardized treatment.