Laminectomy Adjacent to Instrumented Fusion Increases Adjacent Segment Disease

Area of Science:

• Spine surgery outcomes
• Adjacent segment disease research
• Spinal fusion complications

Background:

• Laminectomy adjacent to instrumented fusion has uncertain outcomes.
• Increased mechanical forces at unfused levels may lead to adjacent segment disease (ASD).
• Limited research exists on ASD development following adjacent laminectomy after spinal fusion.

Purpose of the Study:

• To determine if simultaneous laminectomy at an unfused level adjacent to instrumented fusion increases ASD risk.
• To evaluate the impact of adjacent laminectomy on revision surgery rates and timing.
• To analyze the relationship between adjacent laminectomy and ASD development post-spinal fusion.

Main Methods:

• Retrospective cohort study of 789 patients undergoing instrumented lumbar fusion and laminectomy.
• Comparison between patients with (n=113) and without (n=676) an additional adjacent level laminectomy.
• Minimum 2-year follow-up assessing ASD development, time to ASD, revision surgery, and time to revision.

Main Results:

• The adjacent laminectomy group had a significantly higher ASD rate (57.5%) compared to the nonadjacent group (35.2%) (P <0.001).
• Revision surgery rates were also higher in the adjacent laminectomy group (22.1% vs. 13.5%) (P <0.001).
• No significant difference was found in the time to ASD development or revision surgery between groups.

Conclusions:

• Performing laminectomy adjacent to instrumented fusion increases the rate of adjacent segment disease (ASD).
• This surgical approach also elevates the rate of revision surgery.
• Caution is advised for surgeons considering laminectomy adjacent to instrumented spinal fusion.