Lumbar pain and knee pain can be caused by the following reasons: First, lumbar disc herniation, lumbar disc herniation can compress the nerves and lead to lumbar pain, and at the same time, there can be pain in the anterior side of the thighs and the knees, which is often caused by high lumbar disc herniation, such as lumbar 2,3 and lumbar 3,4 disc herniation, which has to be checked in the early stage of the lumbar intervertebral disc CT and MRI to diagnose and treat. Secondly, lumbar spinal stenosis, lumbar spinal stenosis can also compress the nerves and cause lumbar pain, accompanied by knee pain, can be accompanied by claudication, then check the lumbar spine X-ray film, MRI to diagnose, early treatment, and if necessary, need surgical treatment. Third, lumbar vertebrae disease, when the lumbar vertebrae have tumors or tuberculosis, can compress the nerves and lead to lumbar pain, leg pain symptoms, this time to early blood tests and check the lumbar vertebrae MRI to diagnose.