Lumbar isthmic fracture is a unilateral or bilateral isthmic defect of the vertebral arch and is a common cause of chronic low back pain in adolescents. When a patient develops intractable low back pain that seriously affects the quality of survival, treatment is required at this time, and if conservative treatment is ineffective, surgery needs to be considered. Surgical treatment of isthmic fractures includes intersegmental fusion and isthmic repair. Conventional lumbar segmental fusion is prone to loss of lumbar motion phase and accelerates disc degeneration in adjacent segments, and is not suitable for young patients with simple low back pain and no obvious lumbar slippage. The isthmus repair has the advantage of restoring the physiological state of the lumbar spine and preserving the motion phase of the lumbar spine, which is ideal for treating young patients with lumbar disc degeneration or mild lumbar slippage. Typical case: The patient was a 17-year-old male who was admitted to the hospital with “lumbar pain with numbness and pain in both lower limbs for more than 3 months”. The pain radiated along the waist and both buttocks to the back of the thighs bilaterally, and conservative treatment was ineffective. The patient was only 17 years old, and the preoperative examination suggested that L5/S1 had bilateral isthmic fissures and I° slippage of the vertebral body, and there was no degeneration of the intervertebral disc, which was in line with the indications for this operation, and the symptoms disappeared almost completely after the operation, with very satisfactory results. Preoperative CT film: Postoperative X-ray.