Open internal fixation refers to a posterior median incision along the spinous process in the back, severing the attachment point of the muscle to the spinous process, and severing and stripping the attachment point of the muscle in the back on the vertebral plate, followed by nerve decompression, disc removal, bone graft fusion, and internal fixation with an arch nail. Minimally invasive internal fixation refers to the operation of nerve decompression, disc removal, bone graft fusion, and internal fixation of the pedicle through the normal muscle gap without cutting the attachment points of the muscles to the spinous process through a median incision 2 cm from the posterior median. Compared with open internal fixation, minimally invasive internal fixation has the advantages of small incision (about 3cm, while open internal fixation is about 10cm), less bleeding during surgery (generally less than 100ml, compared with 200-400ml for open surgery), less bleeding after surgery (generally less than 100ml, compared with 200-400ml for open surgery), less muscle damage (without cutting the muscle attachment point), fast recovery after surgery, and good long-term effect. Good long-term results.