Extended One-level Interbody Fusion for Adjacent Vacuum Phenomenon in Lumbar Degenerative Disc Disease

For patients who have vacuum signs in the intervertebral disc adjacent to the surgical segment but are asymptomatic and not unstable, the intervertebral fusion surgery is extended to one segment and followed up immediately after surgery, 3 months, 6 months, and annually within 1 to 5 years. Take lumbar spine MR to determine the degree of degeneration progression of adjacent segments and whether revision surgery is needed. Take X-rays of the lumbar spine in frontal and lateral + flexion and extension positions, and CT-three-dimensional reconstruction to judge the bony fusion of the intervertebral fusion.