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Updated: May 14, 2026
07:44
Transforaminal Full-Endoscopic Lumbar Foraminotomy Under Local Anesthesia for L5/S1 Adjacent Segment Foraminal Stenosis
Published on: October 17, 2025
Additional decompression at adjacent segments leads to adjacent segment degeneration after PLIF
Masayuki Miyagi1, Osamu Ikeda, Seiji Ohtori
1Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan. masayuki008@aol.com
Summary
Adjacent segment degeneration (ASD) is more common after posterior lumbar interbody fusion (PLIF) when adjacent levels also undergo decompression. Surgeons should preserve posterior structures to minimize complications in these cases.
Area of Science:
- Spine surgery
- Orthopedics
- Neurosurgery
Background:
- Adjacent segment degeneration (ASD) is a known complication following lumbar fusion.
- Previous studies have explored ASD after PLIF, but the impact of additional decompression at adjacent levels remains unclear.
Purpose of the Study:
- To investigate the incidence and characteristics of ASD in segments adjacent to PLIF.
- To determine if additional decompression surgery at adjacent levels increases the risk of ASD.
Main Methods:
- Retrospective analysis of 23 patients who underwent PLIF surgery.
- Evaluation of 40 adjacent spinal segments (25 decompressed, 15 non-decompressed).
- Assessment of ASD using X-ray films and clinical outcomes.
Main Results:
- ASD was observed in 47.5% of adjacent segments, with 22.5% being symptomatic.
- ASD occurred significantly more frequently in decompressed adjacent segments (64.0%) compared to non-decompressed segments (20.0%) (p < 0.01).
Conclusions:
- Additional decompression above or below the PLIF level is associated with a higher incidence of ASD.
- Surgical strategies that preserve posterior complex structures are recommended when adjacent segment decompression is necessary.
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