If patients have frequent leg pain, it may be due to the presence of old injury, joint inflammation, and osteoporosis in the lower limbs, as follows: First, old injury: some patients may have such symptoms secondary to old injury in the lower limbs. If the patient has a previous comminuted fracture in the lower extremity, and after recovery does not get a good healing, it may lead to the local legacy of sterile inflammation, followed by long-term pain at the injury. Second, joint inflammation: Some patients may suffer from joint inflammation of the lower extremity, which may lead to such symptoms. After the patient develops osteoarthritis of the knee joint, there may be a continuous progression of the disease, which then leads to prolonged pain in the lower extremity. Third, osteoporosis: Some patients may also experience a decrease in bone density in the lower extremities due to osteoporosis, which may lead to these symptoms.