When Spinal Fusion Does Not Fuse: Pseudarthrosis Explained and What Revision Involves

The first year after a lumbar fusion often follows a familiar arc. The incision heals, the walks get longer, the brace comes off, and somewhere around month four a person starts to believe the operation worked. Then, for some, the story bends. A dull ache creeps back into the low back. Bending to tie a shoe brings a sharp, mechanical catch. A follow-up X-ray shows a faint dark line where solid bone should be.

Hearing the words failed spinal fusion in a clinic room can feel like a verdict. It is not. Pseudarthrosis, the medical term for a fusion that has not knitted, is one of the better-understood complications in spine surgery, with recognizable causes, reliable ways to confirm it, and a set of options that range from watchful waiting to revision.

This explainer walks through what is happening in the bone, why some fusions stall, how surgeons decide when to act, and what a second operation actually involves.

What is a failed spinal fusion, and is it the same as pseudarthrosis?

The two phrases overlap but are not identical, and the difference shapes everything that follows. Pseudarthrosis, literally a “false joint,” is a precise finding: the bone graft placed between two vertebrae has not turned into a continuous bridge of living bone, so a small amount of motion persists where none was intended. Surgeons also call this a nonunion.

Failed spinal fusion is a wider, more everyday label. People use it for pseudarthrosis, but also for a screw that has loosened, a rod that has cracked, a new problem at the level above or below the fusion, or simply pain that never improved even though the bone healed perfectly. That last group has its own name, failed back surgery syndrome, which Cleveland Clinic describes as persistent or recurring pain after spine surgery regardless of whether the fusion itself is solid.

Why does the distinction matter? Because the fix is different. A confirmed nonunion is a structural problem that can, in principle, be corrected by getting bone to heal. Pain with a solid fusion is a different puzzle, one that often calls for a search elsewhere: a neighboring disc, a nerve that was compressed too long, a hip or sacroiliac joint doing an impression of back pain.

A useful mental model: the fusion is a bridge under construction, and the screws and rods are the scaffolding. Scaffolding is meant to hold things steady while the permanent structure sets. If the concrete never cures, the scaffolding eventually fatigues. That is pseudarthrosis. If the concrete cured beautifully but the road still has potholes, the bridge did its job and the trouble lies somewhere else. The rest of this article focuses mainly on the first scenario, while flagging where the second one hides in plain sight.

How is a spinal fusion supposed to heal? What actually happens in the bone

Spinal fusion borrows its biology from fracture healing. During the operation, the surgeon roughens or removes the surfaces of the vertebrae to be joined and packs the space with bone graft, which may come from the patient’s own pelvis, from a donor, or from synthetic substitutes. Metal screws and rods, or an interbody cage placed where the disc used to be, hold the segment still. Mayo Clinic notes that the hardware is there to keep the vertebrae from moving while the bone heals, and that this healing takes several months.

The graft itself does not become the fusion. It acts as a lattice. Over the first weeks, blood vessels grow into it, immune cells clear debris, and bone-forming cells called osteoblasts arrive from the living vertebral surfaces. They lay down soft new matrix, which mineralizes into woven bone, which is then remodeled into stronger lamellar bone over months. The metal buys time for this slow sequence.

Three conditions have to hold at once for the bridge to form. The graft must touch bleeding, living bone on both sides, because bone only grows from bone. The blood supply must be good enough to deliver oxygen and cells. And the segment must be stiff enough that the fragile early matrix is not repeatedly torn. Fail any one and the body defaults to what it does with any wobbly healing site: it forms fibrous tissue and cartilage instead of bone. That soft, mobile seam is the pseudarthrosis.

The timeline is longer than most people expect. Skin heals in two weeks, and muscle soreness fades in two months, so it is natural to assume the spine is finished too. Underneath, the bone is often still in the middle of its work.

Why does a spinal fusion fail to fuse?

Nonunion rarely has a single cause. Surgeons tend to sort the contributors into two bins, biology and mechanics, and a stalled fusion usually has a foot in each.

On the biology side, nicotine sits at the top of nearly every list. It constricts small blood vessels and impairs the bone-forming cells the graft depends on, which is why Mayo Clinic and Cleveland Clinic both identify smoking as a risk factor for fusion failure. The effect applies to vaping and nicotine patches as well as cigarettes, since it is the nicotine, not the smoke, that starves the graft. Diabetes with poor glucose control, osteoporosis, long-term corticosteroid use, malnutrition, and chronic kidney disease all slow bone formation. Some evidence links routine use of nonsteroidal anti-inflammatory drugs in the early weeks to slower fusion, though the findings are mixed, and any change to pain medicine belongs with the prescribing clinician.

Mechanics is about motion and load. The more levels fused, the longer the construct and the more places for a seam to open; a fusion that crosses the lumbosacral junction, where the spine meets the pelvis, carries especially high stresses. Hardware that is undersized for a heavy frame, a graft bed that was not prepared down to bleeding bone, or a return to heavy lifting before the bone was ready all add strain.

Then there is the quiet contributor: low-grade infection. A small colony of bacteria around a screw can prevent bone from ever consolidating without producing fever or a red incision. When a fusion stalls for no obvious reason, the workup often includes blood markers of inflammation and, sometimes, sampling of the site during revision.

Knowing the mix matters because revision only succeeds if the reasons for the first failure are addressed, not just the hardware swapped.

Failed spinal fusion symptoms: what a nonunion can feel like

Pseudarthrosis does not announce itself with a unique signature, and that is the first honest thing to say about it. Its most common pattern, though, is a story rather than a single symptom.

Many people describe an early honeymoon. The pre-surgery pain eases, activity climbs, and life feels close to normal for a stretch of months. Then a deep, aching low back pain returns, often worse with standing, walking, or the transition from sitting to upright, and better lying down. Some notice a mechanical quality, a sense of the back “giving” or catching, that they did not have before. If a screw has loosened enough to irritate a nerve root, pain may radiate into a buttock or leg, mimicking the original sciatica.

Other people feel nothing at all. Cleveland Clinic points out that pseudarthrosis can be entirely asymptomatic and discovered only on routine imaging. A fibrous nonunion can be stiff enough to behave, for practical purposes, like a fusion.

The overlap with other problems is wide. The same recurrence of back pain can come from the disc above the fusion wearing out, from a compressed nerve that has been slow to recover, from sacroiliac joint strain, from a hip, or from muscle deconditioning after a long recovery. None of these can be told apart by how the pain feels. That is why this section is deliberately not a checklist. The pattern of pain returning after a period of improvement is a reasonable prompt to book a review with the surgical team, and imaging, not symptom matching, is how the question gets answered.

How is pseudarthrosis after spinal fusion diagnosed?

Confirming a nonunion is harder than it sounds, because metal, healing bone and fibrous tissue can all look similar in the early months. Surgeons therefore lean on a combination of time, imaging and clinical judgment.

Plain X-rays come first. Bending films, taken with the patient flexing forward and arching back, look for movement between the fused vertebrae; a solid fusion should not move at all. Radiologists also look for a dark rim of bone loss around screws, called a halo, or for a rod or screw that has broken. Hardware breakage is a strong clue, since metal only fatigues when it has been flexing repeatedly, which happens when bone has not taken over the load.

Computed tomography, or CT, is the workhorse for the fusion mass itself. Thin slices reconstructed in multiple planes can show whether a continuous bridge of bone runs from one vertebra to the next or whether a gap persists. MRI is less useful here because metal distorts the image, though it remains valuable for looking at nerves, discs and possible infection around the construct.

Timing is the piece patients find most frustrating. Because fusion can keep maturing well past the six-month mark, surgeons are cautious about labeling a nonunion too early. Cleveland Clinic’s overview describes pseudarthrosis as a fusion that has not healed after roughly a year, and many teams will repeat imaging across that period rather than act on a single scan.

Even then, imaging is not perfect. Some nonunions are only confirmed when the surgeon is looking directly at the site during revision. When the picture is unclear and symptoms are tolerable, a decision to wait and rescan is not indecision; it is the evidence-based path.

Spinal fusion not healing on a scan but no pain: does it need fixing?

This situation comes up more often than people expect, and the short answer is: not necessarily. A pseudarthrosis that is stable, painless and not threatening any nerve is a finding, not an emergency.

The reasoning runs like this. The purpose of the original fusion was to relieve pain or protect nerves by stopping abnormal motion. If a fibrous nonunion has become stiff enough that the person is comfortable and functional, the goal has been partly met even though the anatomy is not textbook. Cleveland Clinic notes that treatment for pseudarthrosis depends on symptoms; an asymptomatic nonunion may simply be monitored.

Monitoring usually means periodic X-rays, watching two things in particular. The first is the hardware: screws that begin to halo or rods that show early fatigue suggest the construct is doing more work than it should, and metal under continuous cyclic load does eventually break. The second is alignment: if the vertebrae start to shift, tilt or settle, the nonunion is no longer behaving like a fusion.

There are situations where surgeons lean toward acting even without pain. A nonunion that sits at the bottom of a long fusion, where forces are highest, or one in a person with progressive deformity, may be revised to prevent a bigger problem later. Someone whose work involves heavy loading may be counseled differently from someone with a desk job. These are individual conversations, and the treating team weighs the risks of a second operation against the risks of leaving things alone.

What is not supported by evidence is the idea that every nonunion must be operated on. Surgery treats symptoms and instability, not X-ray findings in isolation.

Who is usually offered revision surgery, and who is asked to wait?

Revision for a failed spinal fusion is a significant undertaking, and most spine teams apply a fairly consistent set of filters before recommending it.

Revision tends to be discussed when three things line up: the nonunion has been confirmed on imaging, usually after around a year as described earlier; the person’s symptoms are meaningful and match the level in question; and a period of nonsurgical care has not brought them to an acceptable place. Broken or loosened hardware, progressive slippage of the vertebrae, or new nerve compression at the nonunion strengthen the case considerably, because these are mechanical problems that time will not solve.

Being asked to wait is common, and it is rarely a dismissal. The most frequent reason is nicotine. Because it directly undermines bone healing, many surgeons will not schedule a revision fusion until the person has been nicotine-free for a sustained period, sometimes confirmed with a urine or blood test. Poorly controlled diabetes, untreated osteoporosis and low vitamin D are similar: fixable contributors that, left alone, would set the second fusion up to fail like the first. A suspected low-grade infection needs to be investigated and, if present, treated before or as part of any revision.

Surgeons also pause when the pain does not clearly originate from the nonunion. If bending films show no motion, the hardware is intact, and the pain pattern points to the adjacent disc or the sacroiliac joint, revising the fusion could put someone through a large operation for a problem it will not address. Diagnostic injections, careful examination and sometimes a second imaging opinion are used to sort this out.

Finally, some people are simply too early. Six months of aching with an immature but unbroken fusion is not the same as a year of confirmed motion.

What does revision spinal fusion surgery involve?

A revision aims to give the bone a second, better chance to heal, which means correcting whatever went wrong the first time rather than repeating it. The specific plan varies, but most revisions include several of the following steps.

The surgeon exposes the old fusion, often through scar tissue, and inspects the site. Loose or broken hardware is removed. The fibrous pseudarthrosis tissue is cut away, and the vertebral surfaces are freshened down to bleeding bone, because bone only grows from bone. New graft is packed in, frequently a larger quantity than before. Fresh, and often more robust, instrumentation is placed, sometimes extending the fusion by a level to gain stronger anchor points.

A key decision is whether to add support from a second direction. Many first fusions are done from the back only. Adding an interbody cage between the vertebral bodies, placed through the front, the side, or a posterior corridor, creates what surgeons call a circumferential or 360-degree fusion, distributing load across more surface area.

Element of revision	What it adds	Typical considerations
Hardware removal and replacement	Removes loose or fatigued metal; restores rigidity	Old screw tracks may need larger screws or new trajectories
Debridement of nonunion	Clears fibrous tissue so bone can bridge	Tissue may be sent for culture to check for infection
Interbody cage (front, side or back approach)	Load sharing across a broad surface	Second approach adds operative time and its own risks
Extension of fusion levels	Stronger fixation points, especially at the pelvis	Longer construct, more stiffness above and below
Fresh bone graft or biologic	New scaffold and cells for healing	Autograft harvest adds a donor-site incision

Johns Hopkins Medicine notes that revision spine surgery is generally more complex than a first operation, in part because of scar tissue and altered anatomy. Operative time is often longer, and the team may involve more than one surgeon. Risks mirror those of any fusion, including infection, bleeding, nerve injury, blood clots, and the possibility that the revision also fails to fuse; they are discussed individually during consent.

Bone graft, biologics and bone stimulators: what the evidence shows

Because a revision is fundamentally an attempt to make bone grow where it previously did not, the choice of graft material gets more attention the second time around.

Autograft, bone taken from the person’s own body, most often the crest of the pelvis, remains the reference standard. It brings living cells, growth factors and a scaffold in one package. Its drawbacks are a second incision, harvest-site pain and a limited supply. Allograft, processed donor bone, provides scaffold without cells. Synthetic substitutes made from ceramics such as calcium phosphate offer scaffold alone. Surgeons frequently combine materials, using autograft where healing is most critical and extenders elsewhere.

Biologics are a class of added growth signals. The best known are bone morphogenetic proteins, laboratory-made versions of molecules the body uses to recruit bone-forming cells. They are approved for specific spinal uses and used off-label in others. The evidence shows they can increase fusion rates in some settings, but they carry documented concerns including excess bone growth in unwanted places, local swelling and fluid collections, and the data have been contested. Whether a biologic is appropriate is a judgment call that belongs to the surgeon, weighed against the person’s specific risk profile.

External bone growth stimulators, small devices worn over the fusion that deliver pulsed electromagnetic fields or ultrasound, are sometimes prescribed after revision. The evidence base is modest and mixed: some trials suggest benefit in higher-risk patients, others show little effect. Guideline bodies generally describe them as an option rather than a standard. They are not a substitute for the fundamentals: stable fixation, a well-prepared graft bed, no nicotine and controlled glucose.

What patients can act on sits mostly outside the operating room. Adequate protein and calcium intake, vitamin D that has been checked and corrected under medical direction, and complete avoidance of nicotine do more for the graft than any additive.

Alternatives to revision surgery for a failed spinal fusion

Not every symptomatic nonunion ends in a second operation, and for many people a structured nonsurgical program is either the first step or the whole plan.

Physical therapy focused on core and hip strength reduces the load passing through the lumbar segment and addresses the deconditioning that almost always follows a long recovery. Therapists also coach movement patterns, teaching how to lift, turn and rise from a chair with less shear through the spine. The NHS emphasizes graded activity and early walking after spine surgery, and the same principle applies when healing has stalled.

Medicines are used for symptom control rather than to heal bone. Simple analgesics act on pain signaling; short courses of anti-inflammatories may be considered with awareness of the debate about their effect on fusion; nerve-modulating medicines target radiating pain. Each has a mechanism and a typical timeframe over which benefit becomes clear, and every choice, including whether to continue or stop, rests with the prescribing clinician.

Image-guided injections serve two purposes. Steroid injections around an irritated nerve can ease radicular pain for a period. Diagnostic injections into a facet or sacroiliac joint help establish whether the pain truly comes from the nonunion or from a neighbor, information that shapes any later surgical decision.

For people whose main problem is persistent pain rather than instability, Cleveland Clinic lists spinal cord stimulation among options for failed back surgery syndrome. A small implanted device delivers electrical pulses to the spinal cord to alter how pain signals are processed; it does not fix the bone but can change the experience of pain.

Treating osteoporosis, controlling diabetes and stopping nicotine are alternatives in their own right, because each improves the odds that a fibrous nonunion consolidates on its own or that any future revision heals.

What the days and weeks after revision fusion usually look like

Recovery from a revision follows the same shape as recovery from a first fusion, usually with a slightly longer runway because the operation is bigger and the tissue has been through it before.

The hospital stay is commonly measured in days. The NHS describes a typical stay after lumbar spine surgery of around one to four days, and MedlinePlus notes that people are generally encouraged to get up and walk within a day of a fusion. Early walking is not optional; it lowers the risk of blood clots, keeps the lungs clear and starts the process of relearning movement. Pain is managed with a plan set by the team, and a brace may be issued depending on the construct.

The first six weeks are about protecting the graft. That means no bending deeply, no twisting, and no lifting anything heavier than a light grocery bag, restrictions the team spells out precisely. MedlinePlus indicates that simple daily activities usually return over roughly four to six weeks, with driving and desk work often resuming in that window once off stronger pain medicines.

From six weeks onward, physical therapy typically begins in earnest, building endurance and core control. Mayo Clinic notes that it takes several months for the bones to heal after fusion, and the NHS advises that full recovery after a fusion can take up to a year. Follow-up X-rays at intervals track the graft as it matures; a CT scan may be ordered later if there is any doubt.

Throughout, the two variables most within the person’s control are nicotine and adherence to activity limits. Everything else is the bone’s timetable, and it does not hurry.

What people often get wrong about failed spinal fusion

A few misconceptions come up in nearly every clinic conversation about nonunion, and correcting them tends to lower anxiety rather than raise it.

The first is that a broken screw or rod means disaster. In fact, hardware breakage after a fusion has solidly healed is often harmless; the metal was going to be redundant anyway. Broken hardware matters when it signals that the bone never took over the load. The X-ray tells the difference, not the fracture itself.

The second is that pain equals nonunion, and its mirror image, that a solid fusion guarantees no pain. Cleveland Clinic’s description of failed back surgery syndrome exists precisely because people can hurt with perfect bone healing, while others walk around comfortably with a fibrous seam. Imaging and symptoms have to be read together.

Third, many assume that a fusion which has not healed at six months has failed. Bone matures slowly, and surgeons generally withhold the label until around a year, as described above. A stalled scan at six months is a reason to keep watching, not to book an operating room.

Fourth is the belief that supplements, a particular diet or a bone stimulator can substitute for the fundamentals. Nutrition and vitamin D matter, but nothing sold over a counter overcomes ongoing nicotine exposure or uncontrolled blood sugar.

Fifth, people often expect revision to be pointless because the first operation did not work. The logic runs backward: revision is designed around the reasons for the first failure, and a clear cause, such as a smoker who has quit or hardware that was too small, is a reason for measured optimism rather than despair.

Finally, some assume the surgeon who did the first operation cannot or should not do the second. Continuity is often valuable; a second opinion is also entirely reasonable. Neither choice implies blame.

Questions to ask your care team about a nonunion

A good consultation about a stalled fusion is a two-way exchange. The questions below are meant to be adapted, and the answers will differ for every spine and every person.

• Is the nonunion confirmed, or is this an immature fusion that may still heal? Which imaging led to that conclusion, and would a CT add clarity?
• How confident are you that my pain is coming from the nonunion rather than an adjacent level, a joint or a nerve? Would a diagnostic injection help sort that out?
• What do you think caused the first fusion to fail, and what would be done differently this time?
• Is the hardware intact? If a screw or rod has broken, what does that tell us?
• Are there factors I should correct before any surgery: nicotine, blood sugar, bone density, vitamin D, weight, medicines?
• If we wait, what are you watching for on follow-up imaging, and how often would you scan?

Should revision be recommended, a second set of questions follows naturally. Ask which approach is planned and whether a second approach, from the front or side, is proposed. Ask about the graft material, whether any biologic is being considered and why, and what the known risks of that choice are. Ask how many levels the revision would involve and whether the construct would extend to the pelvis. Ask how long the operation is expected to take, how long the hospital stay usually is for this type of revision, what the activity restrictions will be and for how long, and what signs would prompt an urgent call afterward.

It is entirely reasonable to ask how the team’s plan compares with published guidance, and to request time to consider. Written notes or a companion in the room help; these conversations carry a lot of detail.

When to call your doctor: red flags after fusion or revision

Most symptoms after spinal fusion, and most of the ache associated with a nonunion, evolve slowly and belong in a scheduled appointment. A small number do not wait.

Seek urgent medical attention, through emergency services if needed, for new weakness in one or both legs, numbness spreading in the saddle area between the thighs, or any new difficulty controlling the bladder or bowels. The NHS and MedlinePlus both flag these as signs of possible nerve or spinal cord compression, which can become permanent if not addressed quickly. The same urgency applies to sudden, severe back pain after a fall or awkward movement in someone with known hardware, since this can indicate breakage or shifting of the construct.

Call the surgical team the same day for signs of infection: fever or chills, an incision that becomes increasingly red, warm, swollen or begins leaking fluid or pus, or new wound separation. Deep infection around spinal hardware can be subtle, so persistent fever without an obvious source also warrants a call. Calf pain, swelling or warmth in one leg, or sudden breathlessness or chest pain, need immediate assessment because blood clots are a recognized risk after any spine operation.

Arrange a prompt but non-emergency review for pain that returns after a clear period of improvement, a new sense of the back giving way or clicking, pain that starts radiating into a leg when it previously did not, or a noticeable change in posture or height. None of these prove a nonunion, but each is a reason to be seen and, usually, imaged.

Every one of these judgments belongs with the treating team, who know the construct, the operation and the person. When in doubt, the cost of a phone call is low.

Frequently asked questions

What is pseudarthrosis after spinal fusion?

Pseudarthrosis is a nonunion: the bone graft placed between two vertebrae during fusion has not grown into a solid, continuous piece of bone, so a small amount of motion remains at that level. The term means false joint. It may cause recurring back pain, or it may be found on routine imaging without any symptoms at all. Diagnosis usually rests on X-rays and CT, and treatment ranges from monitoring to revision surgery depending on symptoms and hardware status.

What are the symptoms of a failed spinal fusion?

There is no single symptom unique to nonunion. The typical story is back pain that eases for months after surgery and then returns, often with a mechanical, giving-way quality that worsens with standing or bending and improves lying down. Leg pain can appear if loosened hardware irritates a nerve. Because adjacent disc wear, joint strain and slow nerve recovery cause identical complaints, imaging rather than symptom matching is needed, and a returning pain pattern is a reason to book a surgical review.

How long after surgery can a spinal fusion still heal?

Bone continues to mature for many months after fusion. Mayo Clinic notes that healing takes several months, and the NHS describes full recovery after a fusion taking up to a year. Surgeons therefore hesitate to call a fusion failed before roughly twelve months, and they often repeat imaging across that period. A scan showing incomplete fusion at six months is usually a reason to keep watching, not proof of nonunion, unless hardware has broken or the vertebrae are shifting.

Does a spinal fusion not healing always need another surgery?

No. If the nonunion causes no pain, the hardware is intact and the alignment is stable, many teams simply monitor with periodic X-rays, since a stiff fibrous seam can function much like a fusion. Revision is generally reserved for confirmed nonunions with meaningful symptoms, broken or loosening hardware, progressive slippage, or new nerve compression. The decision weighs the risks of a second operation against the risks of leaving things alone, and it belongs to the treating team.

What does revision spinal fusion surgery involve?

A revision removes loose or broken hardware, cuts away the fibrous nonunion tissue, freshens the vertebral surfaces down to bleeding bone, and packs in new graft. New instrumentation is placed, sometimes extending the fusion by a level for stronger anchor points, and surgeons often add an interbody cage from the front or side to share load. Johns Hopkins notes revision spine surgery is generally more complex than a first operation because of scar tissue and altered anatomy.

Why does smoking cause spinal fusion to fail?

Nicotine narrows the small blood vessels that must grow into the graft to deliver oxygen and bone-forming cells, and it directly impairs those cells. The graft is essentially a construction site that needs a steady supply line; nicotine chokes it. Mayo Clinic and Cleveland Clinic both list smoking among the risk factors for nonunion. Because the culprit is nicotine itself, vaping and nicotine replacement carry the same concern, which is why many surgeons ask for confirmed abstinence before revision.

Can a broken rod or screw be left alone?

Sometimes. If imaging shows the bone has already fused solidly, a fatigued rod or screw is often redundant and can be monitored, since the metal was only ever scaffolding. Broken hardware becomes a concern when it indicates the bone never took over the load, which points to pseudarthrosis, or when a fragment is irritating a nerve or moving. The surgical team makes this call based on bending X-rays, CT findings and symptoms.

How is a nonunion confirmed on imaging?

Surgeons combine plain X-rays, including flexion and extension views that look for motion between the fused vertebrae, with CT scans that show whether a continuous bridge of bone spans the gap. Dark haloes around screws or fractured hardware are supporting clues. MRI is less helpful because metal distorts the image, though it is used to assess nerves and possible infection. Even with these tools, some nonunions are confirmed only when the surgeon sees the site during revision.

What can I do to help a revision fusion heal?

The factors most within your control are avoiding all nicotine, keeping blood sugar well controlled if you have diabetes, following the activity restrictions your team sets, and walking regularly as advised. Adequate protein and calcium intake and correction of low vitamin D under medical direction support bone formation. Bone density treatment may be recommended if osteoporosis is present. None of these guarantee fusion, but each removes a known obstacle to it.

Is pain after a solid fusion the same as a failed fusion?

No. Persistent or recurring pain despite a fully healed fusion is described by Cleveland Clinic as failed back surgery syndrome, and it has different causes: a wearing disc above or below the fusion, a nerve slow to recover, sacroiliac or hip joint pain, or deconditioning. Revising a solid fusion would not address these. That is why teams work to pinpoint the pain source with examination, imaging and sometimes diagnostic injections before proposing any operation.

References

• MedlinePlus: Spinal fusion
• NHS: Lumbar decompression surgery

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.