Knee pain in the leg after a car accident injury may be related to soft tissue injuries, fractures, and structural damage to the knee ligaments and meniscus. 1. After the car accident leg knee landing, if the injury external force is light, will cause local soft tissue strains, skin abrasions will cause pain, general pain is relatively light. 2. If the external force is large, it may cause bone structure injury, such as patella fracture, tibial plateau fracture, femur condylar fracture, etc., after the fracture, it will cause severe pain in the knee joint and activity limitation. 3. Car accident injuries may also cause knee ligament strain or even complete rupture, such as the medial and lateral collateral ligaments, knee cruciate ligament rupture, and meniscus injuries can also cause knee pain. If knee pain is caused by a car accident, it is recommended that the patient go to the hospital to improve the examination, clarify the cause of the disease and receive regular treatment.