Symptoms of soreness and weakness in the legs should be seen by an orthopedic surgeon first because there are many symptoms that can cause soreness and weakness in the legs. The movement and strength of the legs mainly rely on the muscles and nerves of the legs. Once the symptoms of weakness and soreness appear, the first step is to determine whether the muscles of the legs are atrophied, damaged or whether there is inflammation in the legs. It is also necessary to examine the hip joint, which controls the movement of the legs, to determine whether there are pathologies related to the hip joint, such as synovitis of the hip joint, bursitis of the hip joint, periarthritis of the hip joint, pear-shaped muscle syndrome or even necrosis of the femoral head. The lumbar and sacral nerves are the nerves that originate the sciatic nerve that controls leg movement. Once the lumbar and sacral nerves are damaged or compressed, it will cause soreness and weakness in the legs, such as lumbar disc herniation, lumbar transverse synovial syndrome, lumbar spinal stenosis, etc. Generally, through physical examination, the type of disease can be roughly determined, and then targeted examination and treatment can be carried out.