The indications for surgery are clear, but the question is when internal fixation is needed or just simple decompression, in addition to the high cost and the fear of internal fixation. The specific indications are sometimes controversial, so I will describe here the clinical experience of our department and the indications for internal fixation of lumbar spine diseases. The concept of surgical internal fixation for lumbar disc herniation has been introduced in recent years, and its intention is to increase internal fixation and fusion to stabilize the spine and reduce complications such as lumbar instability in the long term, because lumbar spine surgery destroys the stability of the spine. First of all, it is clear that for lumbar disc herniation and lumbar spine slippage, lumbar disc herniation disease lumbar spinal stenosis, recurrence of lumbar spine disease again for revision surgery, surgery removed more vertebral plates, especially multi-segmental total intervertebral resection or even small joint destruction, although one side of the half vertebral plate removal but small joint destruction or postoperative need for long-term lumbar spine weight-bearing activities of young and strong patients. The effectiveness of fusion internal fixation is not to be questioned in the case of high-grade disc herniation and multi-segmental disc herniation. In the absence of evidence of significant instability, internal fixation is not required. Our department tries to preserve as much as possible the complete posterior column structure intraoperatively, and does not rely on more than 1/3-1/2 of the small joint for opening decompression and performing nerve root decompression, and submarine decompression is effective enough for nerve root canal expansion. Therefore, for lumbar disc surgery, internal fixation may be required only if a large number of laminae have been surgically removed, especially for total laminectomy of multiple segments or even destruction of small joints. For young and strong patients with little laminectomy but small joint destruction or who need long-term lumbar weight-bearing activities after surgery, internal fixation is still recommended, mainly for prophylactic purposes. The general principles: 1. try to solve the patient’s problems and reduce long-term complications; 2. the operator should explain to the patient the reasons for having internal fixation before surgery.