The main objective of this study was to validate the clinical effectiveness of interbody fusion with a one-segment extension for the treatment of adjacent segmental space discs in the surgical treatment of lumbar degeneration.

The study will include patients with lumbar degeneration who underwent 1-2 segment interbody fusion, and for patients with vacuum signs but no symptoms and no instability of the discs in the adjacent segments of the operated segments, lumbar interbody fusion will be extended by one segment, and the patients will be followed up annually in the immediate postoperative period, in March, June, and in the period of 1-5 years, and lumbar MR will be taken at the time of follow-up to determine the degree of progression of the degeneration in the neighboring segments, and whether or not revision surgery is needed. The lumbar spine was photographed in the frontal and lateral + anterior flexion and posterior extension X-rays and CT-3D reconstruction to determine the bony fusion of the interbody fusion. In addition, the lumbar spine ODI score was applied for evaluation at the follow-up visit, and the total lumbar spine-related expenses of the patients up to the follow-up visit were recorded.

Inclusion Criteria:

• The age was between 18-60 years old; patients with lumbar degeneration required 1-2 segment interbody fusion, and there were vacuum signs but no symptoms and no instability of the discs in the adjacent segments (power position slip ≤3mm and segmental angle change ≤10°); they agreed with the surgical plan and were willing to undergo long-term clinical follow-up, and signed an informed consent form.

Exclusion Criteria:

• Drug or alcohol abusers; those with abnormal liver or kidney function unsuitable for surgery; those with cardiac insufficiency unsuitable for surgery; those with severe metabolic and endocrine diseases unsuitable for surgery; those with severe lung disorders such as asthma and abnormal lung function unsuitable for surgery; pregnant and breastfeeding women as well as those who are planning to become pregnant in the near future; those who have participated in other clinical trials within 3 months; and those who are not suitable for participation in the experiment in the opinion of the investigator.