Percutaneous lumbar foraminoplasty is the most minimally invasive procedure for the treatment of lumbar spinal stenosis of the lateral saphenous fossa. It is currently only available at our minimally invasive spine surgery center in China, and the surgical instrumentation is a patented technique of Dr. Zhenzhou Li. The surgical incision is only 7-10 mm, and the procedure is performed under local anesthesia, and you can get out of bed the day after surgery. The trauma was minimal and the recovery was very fast. He complained of intermittent claudication, soreness and numbness in the left lower extremity. Lumbar spinal canalography showed stenosis of the left lateral saphenous fossa at L4-5. During the operation, the left L4-5 intervertebral foramen was enlarged and shaped with a special circular sawing system under the surveillance of X-ray fluoroscopy machine, and the enlarged foramen could be seen endoscopically Postoperative CT review showed that the lateral saphenous fossa from the L4-5 disc plane to the L5 arch root plane was effectively enlarged, and the patient’s symptoms completely disappeared after the operation.