To evaluate the clinical efficacy percutaneous transforaminal endoscopic TESSYS technique in the treatment of senile lumbar spinal stenosis.157 senile with lumbar spinal stenosis were prospectively recruited at this study. The subjects in the experimental group received TESSYS operation, and the control group received traditional open surgery for posterior lumbar interbody fusion. The clinical pain relief, indexes of perioperative period, dysfunction of the lumbar spine and clinical effect of the two groups were measured.The operation time of experimental group was (53.32±10.27) min, average blood loss in operation was (50.01±5.74) ml, and length of hospitalization was (6.73±3.21) d, which were all better than the control group (97.46±13.47) min, (172.23±8.61) ml, (13.94±2.15) d, with statistical significance (P < 0.05). The VAS scores at one day, one week, 1 month and 3 months were significantly lower than those before operation (P < 0.05). The VAS scores of the two groups were significantly lower than those of the open surgery group (P < 0.05). ODI scores of patients were significantly lower than those before operation (P < 0.05). The MACNAB scores of the two groups were significantly lower than those of the open surgery group (P < 0.05).Percutaneous transforaminal TESSYS technique is a safe and minimally invasive technique for the treatment of lumbar spinal stenosis in the elderly. Compared with traditional open surgery for posterior lumbar interbody fusion, percutaneous transforaminal endoscopic TESSYS technique has less trauma and does not damage the stability of the spine. It can significantly shorten the hospitalization and operation time, reduce intraoperative fluoroscopy and blood loss, reduce the degree of pain and postoperative complications, and quickly restore daily life function. and thus an effective and more advantageous scheme for the treatment of elderly lumbar spinal stenosis.AJTR Copyright © 2021.