A disc that hurts and a disc that looks bad are not the same disc

PRP FOR THE INTERVERTEBRAL DISC

Intradiscal platelet-rich plasma is one of the more interesting things in this field and one of the easiest to do badly. The difference is almost entirely in patient selection.

The imaging problem, which is worse here than anywhere

Disc degeneration is close to universal with age. Bulges, desiccation, height loss and annular fissures appear at high rates in people with no back pain whatsoever, and their prevalence climbs steadily decade by decade.

So an MRI report describing degenerative disc disease has told you what your spine looks like. It has not told you what hurts. Treating that report rather than the patient is how people end up with a series of procedures aimed at a finding that was never the problem.

Discogenic pain is a specific thing

A disc becomes a pain generator through a fairly well-described sequence. The nucleus loses proteoglycan and water. Load transfers abnormally to the annulus. Fissures form, and — the part that matters — nerve fibers and blood vessels grow inward along those fissures into tissue that is normally aneural.

That ingrowth is why a degenerate disc can hurt while a similarly degenerate disc in the next person does not. The pain requires nerves to have arrived, and the inflammatory environment inside the disc keeps those nerves sensitized.

What PRP is attempting in there

Not to rebuild the disc. Anyone showing you before-and-after MRIs as proof of disc regeneration is overselling something the imaging cannot demonstrate.

The plausible mechanism is environmental: altering the inflammatory milieu inside the disc, influencing the cells that remain, and reducing the sensitization of the nerve fibers that grew in. The outcome people report is less pain in a disc whose appearance has not changed.

The evidence

A prospective, double-blind, randomized controlled trial of lumbar intradiscal PRP found statistically significant improvement in pain and function against control, sustained through follow-up. That is a real result and it is one trial, in a small population, and it has not been replicated at scale.

So the position here is: better supported than most people assume, and thinner than the marketing around it implies. Both are true and you should hear both. How to read a trial in this field.

What has to be established before a needle goes near a disc

This is the one place on the site where the entry requirements are stricter than the treatment. A disc is not a joint you can inject on suspicion and reassess in six weeks — the risk profile below explains why — so four things are established first, in order, and if any of them fails the answer is no.

The pain is axial. Back pain in the back itself, not pain radiating down a leg. Radicular pain from a compressive fragment is a nerve problem with a different anatomy and a different treatment; the disc is merely where it originated.

The disc is the generator. Concordant pain on provocation, or a discogram-supported diagnosis where one has been done. Not an annular tear seen on a scan. Not degenerative change at the level a radiologist happened to mention. The point of the imaging section above is that the picture will not tell you this.

The segment still has something to work with. Preserved disc height, no collapse, no endplate change that says the structural horse has left. And no progressive weakness, numbness, or bowel and bladder change — that is surgical territory, urgently, and today rather than after a course of injections.

The non-procedural work has genuinely happened. A real course of loading and behavioral work, done properly, not a handout given six months ago.

Meet all four and this is a reasonable thing to attempt. Miss one and what you need is a better diagnosis, which costs less and is worth more.

The risk that makes this different

Discitis. Infection inside a disc is uncommon and serious — the disc is avascular, which means antibiotics reach it poorly and an established infection is difficult to treat and slow to resolve.

That single risk is why intradiscal work is done under strict sterile technique with antibiotic prophylaxis, why it is not offered casually, and why we talk people out of it rather than into it if the indication is soft. It is a different risk conversation from injecting a tendon, and it should be.

Why the disc stopped tolerating what it used to tolerate

The adult disc is the largest structure in the body with no blood supply of its own. Nutrition arrives by diffusion across the vertebral endplates, which means the disc is unusually exposed to anything that degrades small-vessel supply or thickens what has to diffuse through. That is the mechanism. Here is the evidence for it.

Most risk-factor research is observational and cannot separate cause from consequence — painful backs make people sedentary as readily as sedentary living makes backs painful. Mendelian randomization gets around that by using genetic variants as proxies for lifelong exposure. A 2026 systematic review pooled 20 Mendelian randomization studies of intervertebral disc degeneration and reported these as causal-leaning estimates:

• Time spent watching television — OR 1.78 (95% CI 1.52 to 2.08). The largest modifiable lifestyle effect in the whole analysis, and not the one most people would guess.
• Body mass index — OR 1.26 (1.14 to 1.38), and waist circumference 1.26 (1.04 to 1.53).
• Smoking initiation — OR 1.22 (1.12 to 1.33).
• Triglycerides — OR 1.08 (1.03 to 1.13), and type 2 diabetes 1.05 (1.03 to 1.07).

Read the sedentary figure again. Genetically predicted television time carried a larger effect on disc degeneration than diabetes, triglycerides and body mass index did. A disc is loaded, unloaded and rehydrated by movement; a body that does not move is a disc that does not get its nutrition cycled. That is a more useful instruction than most of what patients are told about their backs.

The blood supply argument, and its honest state

If diffusion is the disc’s only route to nutrition, vascular disease upstream of it should matter. A systematic review of 27 studies examined exactly that. Of the eight studies looking at atherosclerosis or lipid status against clinical back pain and sciatica, four found a positive association with abdominal aortic calcification or lumbar artery stenosis. Of the 21 studies looking at atherosclerosis against disc degeneration or herniation, seven were positive, and eight trials found a positive association between lipid status and disc disease.

Four of eight, and seven of 21. We are quoting those denominators on purpose. The reviewers concluded the evidence supports inadequate blood supply contributing to disc degeneration, and it is a hypothesis with real support rather than a settled fact — which is precisely how we will describe it to you. What it changes in practice is that a lipid panel and a blood-pressure reading are part of a back assessment here, not an unrelated errand. What we measure is on the metabolic health page.

The economics that put you in this chair

Consider the sequence the system actually funds. It will pay for the imaging that finds something in nearly everyone. It will pay for the injection and the fusion. It will not pay for the hour of behavioral work, the loading program, or anything addressing the metabolic terrain the disc is failing in — and it calls the eighty-dollar preventive step unproven while covering the forty-thousand-dollar operation.

That is not anyone acting badly. It is an incentive structure, and incentive structures produce predictable damage without needing bad intentions. The people it lands on hardest are pain refugees — passed between specialties, told the scan is unremarkable, left carrying the implication that this is somehow a failure of will.

It is not. It is physiology with an economic upstream, and nobody explained it because no silo owns it.

What we ask before we go anywhere near a disc

Your glycaemic status, because the disc is fed by diffusion and that diffusion is the first thing insulin resistance degrades. Whether you smoke, for the same reason more bluntly. What your day requires of your spine, in positions and hours rather than job title. And what has already been tried, with dates, because eight months of being told to rest is not the same as eight months of graded loading.

If the answer is that the terrain has never been addressed, treating the disc first is asking a structure with no blood supply to rebuild using materials the body is not currently supplying. Why a pain clinic asks to see your bloodwork.

Where this sits against pain medication

Discogenic back pain is one of the most common routes onto long-term opioids and one of the least satisfying to treat, because the pain is constant, the diagnosis is frequently uncertain, and each new procedure arrives with a fresh promise attached.

Nobody here will require a taper as a condition of being assessed. What we will not do is treat an unidentified disc, because the sequence that follows — a procedure, partial relief, a rising dose, another procedure — is the specific mechanism by which people who came in with back pain leave with two problems. The strictness above is the stewardship position. It is not caution for its own sake.

What people ask before a disc is injected

Will this regrow my disc?

No. The plausible effect is on the environment and the sensitized nerve fibers, not on disc height. What no available treatment does.

My MRI says degenerative disc disease. Do I need this?

Not on the imaging alone — those findings are common in pain-free people. Why we block before we inject.

Is it dangerous?

Discitis is the risk that matters. Uncommon, serious, and the reason for strict technique and prophylaxis. Risks and side effects.

Is it covered by insurance?

No. This is a self-pay practice and does not bill insurance for it — which is a coverage decision by payers, not a statement about the treatment. Coverage and paying for it.

Related reading

• Injury and work comp
• Spine and sacroiliac joint
• PRP for facet joints
• Platelet lysate
• Failed back surgery
• What a static image cannot show after an injury