Spinal fusion (open and minimally invasive)

In one minute

Spinal fusion joins two or more vertebrae (the bones of the spine) into one solid block: the worn disc is replaced with a cage (a small hollow spacer) filled with bone graft, and screws and rods hold the vertebrae still while bone grows across. It is done open, through a midline wound, or minimally invasively (MIS), through small tubes and stab incisions. It is for a slipped vertebra with nerve narrowing, unstable fractures, deformity, tumours, infection and instability at several levels. It needs general anaesthesia; a one-level fusion commonly takes two to four hours, patients stand on the first day, and the stay is several days (a mean of 7.4 days for decompression with fusion in the Swedish trial, shorter with minimally invasive techniques). The team also performs fusion fully endoscopically; where that endoscopic fusion is used is drawn below.

What the operation is

The names describe the direction of approach. PLIF (posterior lumbar interbody fusion) and TLIF (transforaminal, through the nerve exit on one side) work from the back; ALIF (anterior) through the abdomen; lateral and oblique fusions (LLIF, XLIF, OLIF) through the flank beside the psoas muscle. Posterolateral fusion lays bone graft along the back of the vertebrae without a cage. Percutaneous pedicle screw fixation places screws and rods through stab incisions, with or without a fusion, and is the usual tool for fractures. What is removed depends on the problem: the lamina and part of the facet joint to free the nerves, the disc to make room for the cage, or a diseased vertebral body in tumour and infection.

Who it is for

The AANS/CNS (American Association of Neurological Surgeons and Congress of Neurological Surgeons) guideline update of 2014 draws the lines. For stenosis with spondylolisthesis, a slipped vertebra, fusion is considered appropriate to stabilise the spine and prevent later deterioration; the trials it cites, including SPORT (the Spine Patient Outcomes Research Trial), showed better outcomes with surgery, most of it fusion. For stenosis without spondylolisthesis, in the absence of deformity or instability, fusion is not recommended. For low back pain alone, trials found comparable results from fusion and from a structured rehabilitation programme with a cognitive element, and the guideline reserves fusion for pain that has failed conservative care.

Beyond degenerative disease the indications are structural: unstable fractures with torn posterior ligaments, progressive kyphosis or nerve damage; adult degenerative scoliosis with pain and nerve symptoms that fail conservative care; spondylodiscitis that destroys the disc or fails antibiotics; spinal tumours that weaken a vertebra; recurrent herniation with instability and some cases of failed back surgery. It is not for stenosis that a decompression alone can solve, for back pain without a structural cause, for untreated severe osteoporosis in which screws would loosen, or for a spine that would do as well with an endoscopic fusion.

How it is done

For a posterior fusion you lie face down under general anaesthesia. In the open operation a midline incision exposes the spine; in MIS-TLIF two small incisions admit a tubular retractor and the screws pass through the skin. X-ray or navigation guides pedicle screws into the vertebrae above and below. On one side the facet joint is removed to open the nerve exit, the root is protected, the disc is emptied, the cage with bone graft is tapped into the disc space, and rods connect the screws and lock it. ALIF works through an abdominal incision, often with an access surgeon holding the large vessels aside; lateral fusions go through the flank and the psoas with nerve monitoring. For fractures, percutaneous screws go through stab incisions into the vertebrae above and below the break, rods slide under the skin and the alignment is restored; after healing the screws are sometimes removed.

How it compares with the endoscopic alternative

The team performs fusion fully endoscopically, with an interbody cage and percutaneous screws. In the literature that technique is described for one- or two-level degenerative problems: a low-grade slip, a collapsed disc with foraminal narrowing, or instability after decompression, in a patient with adequate bone and no major deformity; the endoscopic fusion page has the details and sources. When no instability is present, an endoscopic decompression alone is usually right: the guideline recommends against adding fusion, and the Swedish trial of 247 patients found no better outcomes at two and five years from adding fusion to decompression, with or without spondylolisthesis, and a longer stay (7.4 versus 4.1 days).

Open or MIS fusion is chosen when the endoscope cannot do the job: deformity corrected across several levels, unstable fractures, tumours needing removal and reconstruction, infection needing debridement, high-grade slips, revisions through scar, severe osteoporosis, and cases where the front of the spine must be rebuilt with a large cage. For fractures the MIS tool is percutaneous screws: a pooled analysis of 12 studies found the operation 19 minutes shorter and the stay 5.7 days shorter than open fixation, no difference in screw position or alignment, and an infection rate that was lower but only at the edge of statistical significance (relative risk 0.36, confidence interval 0.13 to 1.00). Between open and MIS fusion, the 2015 meta-analysis found no difference in operating time, median blood loss of 177 versus 461 ml, infections of 1.2% versus 4.6%, and slightly better pain and disability scores after MIS, with more radiation exposure for the team.

Risks and how we reduce them

Nerve root injury, with new weakness or numbness, and a tear of the dura (the sac around the nerves) with a leak of spinal fluid are the risks of working next to the nerves; magnification, careful retraction and imaging for the screws are the answer. Infection occurred in 1.2% of MIS and 4.6% of open TLIF patients in the pooled analysis. Screw malposition did not differ between percutaneous and open techniques in the fracture analysis; surgeons check every screw on imaging before closing. Failure to fuse (pseudarthrosis) leaves the level painful and can loosen the screws; smoking, osteoporosis and diabetes raise the risk, so patients are asked to stop smoking and to have the bone treated first.

Adjacent segment disease is the long-term problem. The 2023 meta-analysis of 15 studies and 6,253 patients found that 720 developed disease at a neighbouring level and 473 had surgery for it; it quotes symptomatic rates of 5 to 30% across the literature, names age and obesity as risk factors, and finds interbody fusion protective. Fusing as few levels as the problem needs and restoring alignment are the surgeon's answer. Lateral fusions pass beside the lumbar nerve plexus, so temporary thigh numbness or hip flexor weakness can follow and usually fades; anterior fusions pass beside the large vessels and the nerves that control ejaculation in men, which is why an access surgeon commonly opens the approach. Reoperation over the years is real: 14% after fusion versus 34% after decompression alone over four years in the SLIP trial, and 22% versus 21% over a mean of 6.5 years in the Swedish trial. Across all the team's operations our complication figure is well below 1%; that is our own figure and not a comparison with anyone else.

Recovery, week by week

What the evidence says

The AANS/CNS guideline update of 2014 supports fusion for stenosis with spondylolisthesis, recommends against it for stenosis without deformity or instability, and finds fusion and structured rehabilitation comparable for back pain alone. Two 2016 trials in the same issue of the New England Journal of Medicine disagree: the SLIP trial (66 patients with grade I spondylolisthesis) found a modestly better physical quality-of-life score and fewer reoperations when fusion was added to laminectomy, and the Swedish Spinal Stenosis Study (247 patients) found no benefit at two or five years. The 2015 meta-analyses favour MIS over open surgery on blood loss, infection and stay, with similar or slightly better pain and disability scores. The 2023 meta-analysis confirms adjacent segment degeneration as the main late complication.

How we do it at spine.uz

We are Tashkent's first endoscopic spine team, five surgeons operating as one, with 27,600+ endoscopic and spine operations in total, and we treat the full range of surgical spine pathology. Fusion, fracture and deformity pages are reviewed by Dr. Shomansur Shotursunov and Dr. Dilmurod Kandimov, orthopaedic surgeons. The team performs fusion fully endoscopically with a cage and percutaneous screws, and the open and MIS operations on this page. The written conclusion says whether the level needs fusing at all, whether the endoscopic fusion fits, or whether deformity, trauma, tumour, infection or multilevel instability call for the open or MIS operation, and why.

The first step is free: send your MRI (magnetic resonance imaging) on Telegram or WhatsApp and a doctor from the team replies by voice within 48 hours. After the operation you receive a written conclusion and the team follows you up on Telegram.

Preparing for the operation

Photograph every slice of your MRI, any CT and standing X-rays, and send them ahead; bring a bone density result if you have one. Bring your list of medicines and tell us about blood thinners; the surgeon decides when to pause them. Stop smoking, control your blood sugar if you have diabetes, and walk daily before surgery. Fast as the anaesthetist instructs and arrange help at home for the first two weeks.