When patients hear that a lumbar fusion will be performed through an incision in the abdomen rather than the back, the obvious question is: why approach the spine from the front?
What is ALIF?
ALIF stands for Anterior Lumbar Interbody Fusion. The disc is accessed from the front of the spine, removed, and replaced with a cage or graft to restore the disc space and achieve fusion.
Why approach from the front?
- Less disruption of the posterior structures: the approach avoids direct posterior muscle dissection and direct posterior nerve-root retraction.
- A larger implant footprint: the anterior corridor allows a large cage with broad contact across the disc space.
- Restoration of anatomy: disc height and segmental lordosis can be restored more powerfully in appropriately selected patients.
Indirect decompression
Restoring disc height can increase foraminal dimensions and tension the surrounding ligaments, potentially relieving nerve compression without direct posterior nerve-root manipulation. This is patient- and pathology-dependent.
When is ALIF useful?
- Degenerative disc disease with disc-height loss
- Selected low-grade spondylolisthesis
- Selected revision cases
- Adult spinal deformity reconstruction
Limitations and risks
ALIF is not appropriate for every patient. Vascular anatomy and approach-related risks must be considered, and significant fixed posterior or central stenosis may require direct decompression. Prior abdominal surgery and other anatomical factors can influence the choice of approach.
The bottom line
The decision to approach from the front, back, or both should be based on the problem that needs to be solved — not simply surgeon preference.