What they are
Both TLIF and PLIF are posterior approaches — performed through an incision in the back — that place an interbody graft (a cage filled with bone graft) into the disc space from behind, combined with posterior pedicle screw fixation.
TLIF (Transforaminal Lumbar Interbody Fusion): The disc is accessed through the foramen — the opening where the nerve root exits — from one side, after removing the facet joint on that side. The nerve root is minimally retracted. A single cage is placed obliquely in the disc space. TLIF has largely replaced PLIF as the preferred posterior interbody technique because it requires less nerve retraction.
PLIF (Posterior Lumbar Interbody Fusion): The disc is accessed directly from behind, with bilateral retraction of the thecal sac and nerve roots to place cages on each side. More nerve manipulation is required than with TLIF. Still used in specific circumstances.
Why posterior interbody fusion rather than decompression alone
Adding an interbody graft to posterior pedicle screw fixation improves fusion rates compared to posterolateral fusion alone, restores disc height, and helps correct sagittal alignment. In spondylolisthesis, the interbody cage also acts as a structural buttress that helps maintain slip reduction.
For patients who need both decompression (to relieve nerve compression) and fusion (to address instability), TLIF is often the most efficient approach — it accomplishes both goals through a single posterior incision without requiring an additional anterior or lateral procedure.
Minimally invasive TLIF
TLIF can be performed through smaller incisions using tubular retractors and percutaneous pedicle screws — minimally invasive TLIF (MIS-TLIF). This reduces muscle disruption, blood loss, and hospital stay compared to open TLIF in appropriately selected patients. The technique requires experience but offers meaningful recovery advantages.
What to expect
Hospital stay after TLIF is typically two to four days. Recovery from lumbar fusion — fusion maturation, activity progression — takes three to six months. Most patients with leg symptoms notice improvement in the early weeks; back pain recovery is more variable.