Anterior-Posterior Lumbar Fusion

What it is

An anterior-posterior lumbar fusion — surgeons call it a 360° or circumferential fusion — stabilizes a level from both columns of the spine in a single surgical plan. In the anterior stage, performed with an access surgeon handling the abdominal approach, the damaged disc is removed and a large-footprint cage is placed in the disc space, restoring its height and rebuilding the lumbar lordosis, with graft packed to grow across the segment. In the posterior stage, pedicle screws and rods lock the level from behind, the nerves are decompressed directly if they need it, and additional graft is laid along the back of the spine (the posterior lumbar fusion component).

Neither stage is redundant. The front of the spine carries the majority of the axial load, so the cage sits where the forces are and offers the largest possible surface for fusion. The back provides immediate, rigid control of alignment while that fusion matures. An ALIF alone or a posterior fusion alone is the right operation for most spines — this page describes the cases where one side, honestly assessed, is not enough.

When it may be considered

The combined approach is considered when the problem is structural in a way a single approach cannot fully answer: deformity, such as degenerative scoliosis or a flattened lumbar curve (flatback), where lordosis must be rebuilt and not merely held; revision surgery, where a prior fusion failed to heal (pseudarthrosis) or the level has collapsed after previous operations; high-grade spondylolisthesis, where the slip and the shear forces across it demand circumferential control; and severe disc collapse with foraminal stenosis and instability, where restoring the height of the nerve tunnels requires the anterior reconstruction. It is also the fallback when bone quality or biology makes a single-surface fusion a poor bet.

One anesthetic, or staged

Some circumferential fusions — typically a single level in a healthy patient — are completed under one anesthetic, front then back. Others are deliberately staged across two operations a day or two apart: multilevel deformity corrections, long constructs, or patients whose physiology should not absorb the combined blood loss and anesthesia time in one sitting. Staging is decided in advance and is a feature of the plan, not a complication of it. Either way, this is a bigger undertaking than any single-approach fusion — two incisions, a stay measured in days — and it is recommended only when what it buys is worth exactly that.

What to discuss at consultation

• Goals: a fusion that heals — restore disc height and lordosis from the front, hold them rigidly from the back, and decompress the nerves the collapse has trapped.
• Alternatives: posterior-only fusion (posterior lumbar fusion or TLIF / PLIF) when the disc space does not need rebuilding; anterior fusion as the sole approach in narrow circumstances; continued nonoperative care where the structure tolerates it.
• Recovery: several days in hospital; walking from day one; bending, lifting, and twisting precautions for six weeks; fusion maturation over 3–12 months.
• Risks: the risks of both approaches combined — vascular or visceral injury at the front (minimized by the access surgeon), nonunion (reduced, not eliminated), hardware problems, infection, blood loss, and adjacent segment wear over time.

From Back Talk

Related reading: Lumbar Fusion Recovery: 3 Months · Spinal Fusion Myths

Who is a good candidate

• A prior lumbar fusion that never healed (pseudarthrosis), with pain and imaging that agree on the failed level
• Degenerative scoliosis or loss of lumbar lordosis that requires the curve to be rebuilt, not just stabilized in place
• High-grade spondylolisthesis, where shear forces defeat a single-column construct
• Severe disc collapse with foraminal stenosis and documented instability at the same level
• Bone health and medical fitness addressed in advance — this operation asks more of healing than any other fusion on this site

A 360° fusion treats structural failure, not ordinary back pain. Candidacy begins with proving that the anatomy — the failed fusion, the deformity, the collapsed and unstable level — is truly what generates the symptoms.

What recovery actually looks like

Days 1–4. Hospital stay, walking from the first day after each stage. If the operation is staged, the second stage falls within this window. Two incisions — abdomen and back — are both healing, and early soreness reflects that honestly.

Weeks 2–6. Walking is the activity; bending, lifting, and twisting precautions protect the construct. No formal physical therapy by default in this window — it is prescribed selectively.

Weeks 6–12. Activity expands, X-rays confirm hardware position, and conditioning begins. Staged and single-session patients converge on roughly the same timeline here.

3–12 months. The two fusion masses consolidate. In revision cases, a CT may be used to confirm bridging bone rather than assuming it. Most patients are back toward full activity around three months, with the biology still maturing behind them.

Risks and how they are minimized

The risks are the sum of both approaches and are discussed as such: injury to the great vessels or abdominal contents during the anterior stage; nonunion despite the doubled fusion surface; hardware loosening; infection; dural tear during the posterior decompression; and, over years, wear at the levels adjacent to the construct (adjacent segment disease).

They are minimized by an access surgeon performing the anterior exposure, by navigation-guided implant placement, by staging when physiology demands it, and by treating bone health as part of the operation — nicotine cessation, vitamin D, and metabolic optimization before surgery, because a circumferential fusion cannot out-engineer biology that will not grow bone.

Alternatives considered first

Most lumbar problems never reach this operation. The standard first course is time, activity modification, and physical therapy; when leg symptoms dominate, injections can calm an irritated nerve — Dr. Choi does not perform injections himself and refers patients to pain management colleagues. A single-approach fusion — ALIF-based, TLIF / PLIF, or posterior fusion — is preferred whenever it can honestly achieve the same structural result. The 360° construct is chosen at the point where the deformity, the revision anatomy, or the healing odds say that one approach is a gamble the patient should not have to take.

Related procedures

ALIF · Posterior lumbar fusion · TLIF / PLIF · Revision spine surgery · Spinal fusion

Conditions this procedure treats

Spondylolisthesis · Pseudarthrosis · Degenerative scoliosis · Failed back surgery syndrome · Adjacent segment disease