For leg pain and knee pain, it is necessary to first determine whether there is excessive exercise, i.e., whether there is a history of injury and trauma. First, if the leg pain and knee pain should be considered first, knee joint pathology. Knee pathology includes knee meniscal injury, synovitis, articular cartilage degeneration, osteoarthritis, etc. Secondly, it needs to be considered from above, which may be femoral head necrosis, ischemic necrosis, hip joint lesion. Femoral head necrosis can cause pain in the inner thigh and inner knee joint. Thirdly, then upward consideration is lumbar spine pathology, such as lumbar disc herniation, lumbar degeneration, etc., causing pressure and stimulation of the spinal nerve roots, causing nerve root symptoms, legs and knees can appear pain and numbness at the same time. Therefore, it is best to go to the hospital for examination and treatment when such symptoms occur.