The causes of numbness and woodiness on the right foot are as follows: First, consider a herniated lumbar disc, when the herniated disc tissue presses on the nerve root, numbness in the right foot will occur. If the compression to the lumbar 5 nerve root, the main manifestation is numbness of the skin on the back of the right foot. If the nerve root of sacral 1 is compressed, numbness of the heel and sole of the foot will appear. Second, consider lumbar spinal stenosis, which is mainly due to spinal cord compression caused by lumbar disc herniation, ligamentum flavum hyperplasia or vertebral canal osteophytes, as well as nerve root compression, which can also manifest as numbness of the right foot. Thirdly, it can be considered as ankle canal syndrome, which is mainly due to the compression of the cervical nerve at the ankle canal and can manifest as plantar numbness, abnormal plantar sensation and plantar pain.