Evaluation of the Effect of Revision Surgery of Lumbar Adjacent Segment Degeneration

Inclusion Criteria: * For patients undergoing revision surgery in adjacent segments due to S-ASD, the revision surgery is at least half a year from the first operation; * X-ray, CT and MRI examination data of the anterior and lateral extension of the lumbar spine were available within 1 month before surgery and at the last follow-up; * Follow-up for at least 2 years after revision; Exclusion Criteria: * Patients with history of congenital spinal deformity, spinal tumor, spinal tuberculosis.