Spinal stenosis is more serious than lateral recess stenosis. The main causes of spinal stenosis are osteophytes, bone growth into the spinal canal to compress the spinal nerves. Intervertebral disc herniation, vertebral body slippage, spinal trauma, hypertrophy of the ligamentum flavum, compression of spinal nerves appearing low back pain, walking claudication, compression of the cauda equina nerve appearing urinary and defecation disorders. Treatment is mainly to take the vertebral plate decompression nerve release. Lateral saphenous fossa stenosis is mostly caused by disc herniation and hypertrophy of ligamentum flavum, which compresses the nerve root and causes sciatica. Patients with mild stenosis can be treated conservatively, and if the symptoms are more serious, the lateral fossa can be enlarged and shaped for neurolysis. Therefore, spinal stenosis has more severe symptoms than lateral fossa stenosis and is more complicated to treat.