The ringing in the knee when bending the leg may be related to acute hip dislocation, meniscus injury, bone spurs and other diseases, which can be relieved by medication and surgical treatment. 1. Acute hip dislocation: If acute hip dislocation causes knee ringing when bending the leg, the patient can take celecoxib, ibuprofen and other non-steroidal anti-inflammatory drugs as prescribed by the doctor, which can have the effect of anti-inflammatory and pain relief. Then take manipulation reset, for repeated hip dislocation, patients can be treated by tendon transposition, which can improve muscle function to stabilize the hip bone. 2. Meniscus injury: Meniscus injury may also cause knee ringing when bending the leg, patients can take acetaminophen, aspirin and other painkillers as prescribed by the doctor. For patients with good knee cartilage and high activity level, meniscus replacement can be performed. 3. Bone spurs: knee rattling when bending the leg may also be related to bone spurs, patients can follow the doctor’s instructions for external use of flurbiprofen gel paste and other non-steroidal anti-inflammatory drugs. For patients with significant pain, bone spurs can be removed through minimally invasive arthroscopic surgery. There are many reasons for the ringing in the knee when bending the leg, so it is recommended to go to a regular hospital and cooperate with the doctor for standardized treatment.