Rattling sound when bending and straightening the knee may be caused by physiological popping, chondromalacia patellae, calcification of knee ligament, etc.
1. Physiological popping: If there is a popping sound when the knee joint is moving but there is no pain or discomfort, it is a normal phenomenon, which is caused by the rupture of air bubbles inside the joint when it is moving. Generally no treatment is needed.
2. Chondromalacia patella: In patients with chondromalacia patella, the joint surface of the patella is uneven. When the knee joint moves, the patella does not slide well and it will make a popping sound. Reduce knee activities, it is recommended to wear knee pads to fix the patella during activities.
3. Calcification of knee ligaments: Calcification of knee ligaments after damage will lead to poor joint movement, and the ligaments will rub against the joints and produce rattles.
In addition, knee bending and straightening sound may also be caused by meniscus injury, osteoarthritis and so on. If accompanied by pain, knee flexion and extension is unfavorable, it is recommended that the patient go to the hospital in time, by the doctor for targeted treatment.