Skin incision is about 8 mm at about 7-10 cm away from the midline of the back.
Please see the below. The TF-FESS surgery under local anesthesia initiated by discectomy of the herniated nucleus pulposus. Now, the procedure can be applied for all three types of the lumbar spinal canal stenosis under local anesthesia.

This representable case is a 89 years old female. Four years ago, she had vertebral body fracture, and it was healed with conservative treatment. Although vertebral body was collapsed, severe low back pain was disappeared. Instead, let high pain appeared. Since her cardiac function was very poor, and her age was very elderly, her local surgeons did not recommend surgical intervention with general anesthesia. Then, she was referred to us. Under local anesthesia, her narrow foramen was successfully enlarged by TF-FESS (foraminotomy), and her leg pain disappeared. Please see the figures below, and the circle indicates the change of the foramen before and after surgery.

This representable case is 90 years old male. He visited many local doctors with complaining of the left leg pain. Since he is very old (90 y.o.) and he has general complications; thus, no one recommended surgery. He could not tolerate the pain, and he visited us for the purpose of the surgery under local anesthesia. His left leg pain was induced by the lateral recess stenosis, and FEVF was conducted successfully. His symptoms was completely disappeared after the surgery.

This is the final endoscopic view during the surgery. The decompressed L5 traversing nerve root is clearly observed.

Representable case #1 is demonstrated as below. This is the first case of TE-LUL under local anesthesia in our institution.
This case is 72 years old female, and visited us with both leg pain and muscle weakness at the left side. Interlaminar decompression as ‘laminectomy’ was planned under general anesthesia; however, her pulmonary function was very poor. The laminectomy was cancelled; then, TE-LUL under local anesthesia was conducted instead. After bilateral decompression, her both leg pain was disappeared and the muscle weakness was improved completely within 3 months.

This endoscopic appearance is the final view of the TE-LUL from the left side. The decompressed dural sac is obvious.

The final case is 91 years old female, and visited us with left leg pain and intermittent claudication within 100 m. Her age was over 90 years old and she was afraid of having the general anesthesia. TE-LUL under local anesthesia was conducted. After left side TE-LUL, her left leg pain was totally disappeared.