A Needle in the Neck Is Not a Test: How a Stellate Ganglion Block Is Proven to Have Worked

What this video covers

• What the stellate ganglion is, where it sits at C7 and the first rib, and why the needle aims at the C6 Chassaignac tubercle one level above
• The leading theory of how sympathetically maintained pain starts. Alpha-1 adrenergic receptors appear on injured nerve fibers, so the body’s own adrenaline can drive pain. And why it is still a proposed mechanism, not a settled one
• Why ultrasound guidance matters: seeing the carotid and vertebral arteries, thyroid, esophagus and longus colli muscle instead of relying on surface landmarks
• How a working sympathetic block is confirmed by objective signs: a drooping eyelid, a red eye, and a measurable rise in hand temperature. And why a negative result still has to be read with care
• What the randomized sham-controlled trial in active-duty service members actually showed. Why the evidence for using this block for post-traumatic stress is a single modest trial. And what the Cochrane review on complex regional pain syndrome did not show
• The real risks, from short-lived hoarseness and trouble swallowing to the rare but serious events in the safety literature, including hematoma, pneumothorax and infection
• MEDICAL DISCLAIMER: This content is for educational purposes only and is not medical advice. It does not substitute for professional diagnosis or treatment. Always consult a licensed healthcare provider regarding your condition. Viewing this video does not establish a doctor-patient relationship.

A stellate ganglion block is proven to have worked only when the sympathetic chain is objectively blocked. That means a drooping eyelid, a red eye, and a measured rise in hand temperature, recorded before and after the injection. Without those findings in the chart, a needle went into the neck and produced no information.

Put both hands flat on the table. One of them no longer looks like it belongs to you. The skin across the knuckles is glossy and stretched. The color drifts through the day — mottled and dusky by morning, blotched red by evening. It is colder than the other hand, and you can prove that with a thermometer. A bedsheet dragged across it feels like a burn.

Or there is nothing visible at all. Something happened to you — combat, an assault, a highway crash — and your body never stood down. Your resting heart rate will not settle. You sleep in pieces. A car door closing three houses away puts you on the ceiling.

Both of those patients get sent for the same injection into the front of the neck: a stellate ganglion block. And both are often failed, in two different ways. Some arrive having had three, four, five of these blocks. Not one line in the chart records whether the sympathetic chain was ever actually blocked. No eyelid noted. No hand temperature before and after. A needle went into a neck and the visit produced no information at all. That is not a diagnostic test.

This article explains what the stellate ganglion is. It explains why blocking a nerve that carries no pain fibers can change a burning hand. It shows how a good block is confirmed with objective signs. And it lays out what the published evidence does and does not support.

What is the stellate ganglion, and why is it blocked?

Its reputation misleads people, so start with the anatomy.

The stellate ganglion is not a sensory nerve. It is the fused cervicothoracic sympathetic ganglion, seated at the transverse process of the seventh cervical vertebra, near the neck of the first rib. It is the relay station for sympathetic outflow — the “fight or flight” wiring — to the head, the neck, the upper limb, and the heart.

It carries no pain fibers from your hand.

So why block it for a burning hand? There are two proposed reasons, and they do not stand on equal ground.

Sympathetically maintained pain. In animal models of nerve injury, injured pain fibers begin to carry alpha-1 adrenergic receptors on their surface. Once those receptors appear, norepinephrine — your own adrenaline chemistry — directly fires the very fibers that report damage. The pain system starts answering to the stress system.

Be exact about the status of that idea: it is the leading proposed explanation. It is not proven in humans, and anyone who states it as fact has walked past the data. Treat it as a hypothesis whenever someone uses it to justify a procedure to you.

Sustained sympathetic vasoconstriction. This one you can see. Constant sympathetic tone clamps down the small vessels of the hand. That is the cold, mottled, swollen limb of complex regional pain syndrome. Blood flow falls at the exact moment inflamed tissue needs more of it.

Why that produces the hand you are living with

If the sympathetic system is driving pain fibers directly, the pain no longer matches tissue damage. It tracks arousal instead. That is why a limb can burn worse on a bad day, in a cold room, or after a startle, with nothing new happening to the tissue itself. And it is why the burning does not act the way a healing injury acts.

If the same system is choking blood flow, you get the other half of the picture. There is the coldness you can measure with a thermometer and the glossy, stretched skin. There is the color that drifts from dusky violet to blotched red in a single day. And there is the swelling that will not settle.

Those two mechanisms explain why the hand looks wrong and feels wrong at the same time. They also explain why an X-ray showing a cleanly healed fracture is no comfort at all. The bone is fine. The hand is not.

Then there is the second kind of patient — the one whose nervous system never came down from what happened. The stellate ganglion relays sympathetic outflow to the heart as well as to the hand. This block has been studied in post-traumatic stress in a single randomized trial, described further down this page. What that trial found is more modest than the marketing suggests.

What standard care misses: the differential, and the missing receipt

Two failures dominate, and they make each other worse.

A burning arm is a complaint, not a diagnosis

It has at least five plausible causes. Each has a test that tells them apart and costs nothing compared with a neck injection:

• Cervical radiculopathy at the sixth or seventh nerve root follows a dermatome (the skin strip one nerve root supplies). It comes back with a Spurling maneuver, and it shows up on a nerve study (electrodiagnostic study).
• Thoracic outlet syndrome depends on position — raising the arm sets it off.
• Peripheral polyneuropathy hits both sides in a stocking-glove pattern. In this practice it is often driven by hyperinsulinemia (too much insulin in the blood). No sympathetic block corrects that. Reaching for one instead of a fasting insulin is malpractice by omission.
• Post-herpetic neuralgia sits in one dermatome and comes with a shingles history — which you have to ask about.
• Sympathetically maintained pain is what is left when the others are ruled out, not what you assume at the start.

Every one of those has been injected in the neck by somebody who never sorted them out. And when the injection did nothing, the patient was blamed for being difficult.

The block was never verified

The second failure is quieter and more common. An injection is done and no measurement is recorded. No eyelid. No pupil. No hand temperature before and after. When that happens, a negative result means nothing. Nobody can tell whether the sympathetic chain was blocked and the pain stayed, or the block simply missed. So the injection gets repeated, and the same non-answer comes back again.

There is a commercial version of the same failure. Think of storefronts selling this block as a “nervous-system reset,” cash up front, package of three, with no mental health clinician in the building. That is not medicine either.

How is a stellate ganglion block performed?

The needle does not aim at the ganglion itself. It aims at the Chassaignac tubercle — the front bump (anterior tubercle) of the sixth cervical transverse process, one full level above the structure being blocked. Local anesthetic is placed deep to the prevertebral fascia, over the longus colli muscle. It then spreads downward along that layer.

Going high is on purpose. Lower down, the vertebral artery lies exposed and the top of the lung is close. That level buys margin, and margin is the whole game in the front of the neck.

Ultrasound is not a luxury here. With the older landmark method, the doctor felt for the bump, pushed the carotid aside, and injected into anatomy no one could see. Under ultrasound, you can see the carotid artery, the vertebral artery, the internal jugular vein, the thyroid, the esophagus and the longus colli. The needle tip is watched as it moves into the right layer. Full procedure detail — preparation, what the appointment involves, and recovery — is on our stellate ganglion block treatment page.

What are the signs a stellate ganglion block worked?

This is what separates a diagnostic block from a ritual. A good sympathetic block shows itself with objective signs, within minutes. Every one of these signs belongs in your chart:

• Ptosis and miosis — the eyelid droops and the pupil shrinks on the treated side. That pairing is Horner syndrome, the classic marker that the sympathetic chain in the neck has been interrupted.
• Conjunctival injection — the eye on that side turns red.
• A measurable rise in skin temperature in the affected hand, recorded before and after with a thermometer.

Those signs are the receipt. Ask for them. If nobody measured the temperature of that hand before and after, nobody learned anything.

Here is the reasoning the receipt makes possible. If sympatholysis (a blocked sympathetic chain) is documented and your pain is unchanged, sympathetically maintained pain becomes far less likely — and the plan changes that day. That is a useful answer, not a failure. An injection that has told you it is the wrong lever should not be repeated.

One important caution: a negative result gets interpreted, not obeyed. An incomplete block can produce a false negative. And fibers of Kuntz — sympathetic pathways that bypass the ganglion — can carry signals around the level that was blocked. A single unclear result is a data point, not a verdict.

Does a stellate ganglion block work?

You deserve this straight, because the evidence differs sharply by condition.

For complex regional pain syndrome, the evidence is weak. The Cochrane review by O’Connell and colleagues, published in 2016, pooled 12 studies with 461 participants. It judged every one of them to be at high or unclear risk of bias. It rated the overall quality of evidence low to very low. It concluded that the limited data available do not suggest that local anesthetic sympathetic blockade is effective for reducing pain in this condition.¹ That review’s literature search closed in September 2015. That is a decade-old and thin evidence base.

That finding is not softened here. So in this practice the block is used mainly as a diagnostic instrument, and second as an add-on that opens a window for the work that actually rebuilds a limb. That work is desensitization, graded motor imagery, mirror therapy and progressive loading. The block is the anesthetic for the rehab, not the rehab.

For post-traumatic stress, there is one trial, and it is real and modest. The randomized, sham-controlled trial by Rae Olmsted and colleagues was published in JAMA Psychiatry in 2020. It enrolled 113 active-duty service members randomized 2:1 (74 to block, 39 to sham). Of them, 91 — 80 percent — met full criteria on the CAPS-5, at mild-to-moderate baseline severity.² Participants received two right-sided blocks, at week 0 and week 2. By eight weeks, adjusted symptom scores had fallen 12.6 points (95% CI −15.5 to −9.7) in the block group. With sham, they fell 6.1 points (95% CI −9.8 to −2.3), P = .01.

The authors themselves noted two limits: the mild-to-moderate starting severity and the short follow-up. Both limit how far the findings apply to others. They concluded only that the block merits further trials as a treatment adjunct. Stated plainly: for post-traumatic stress this block belongs alongside trauma-focused therapy and medication, never instead of them. Do not start, stop, or change any medication without consulting your physician.

The risks are uncommon but real. Goel and colleagues, in Regional Anesthesia and Pain Medicine in 2019, screened 1,909 articles published between January 1990 and November 2018. It cataloged 260 reported adverse-event cases across 67 included studies. Imaging guidance was used in 134 of those 260 cases (51.5%). Of the cases, 178 (68.4%) were linked to the drug or the whole body, while 82 (31.5%) were linked to the procedure or the local site.³

• Common and short-lived, and familiar from everyday practice: hoarseness, trouble swallowing, a heavy eyelid. Hours, not days.
• Rare and serious: seizure from intravascular injection (into a blood vessel); hematoma (a pocket of blood) blocking the airway, including the one reported death in that review; and cervical epidural abscess, including the one reported case of quadriplegia.

That review collects reported cases. It does not follow a defined group of people. So it shows what can happen, but it does not give an incidence rate. One procedure rule holds here no matter what any review counted: both sides are never blocked in the same session, because blocking both recurrent laryngeal nerves can endanger the airway. That is a safety rule of practice, not a finding of the review.

And one expectation comes from clinical practice, not from a trial, and it applies to every use: the benefit of a single block is measured in weeks, not years.

What this means for your evaluation

The order is not negotiable. It is the same for both kinds of patient described at the top of this page.

First, settle the differential. Radiculopathy, thoracic outlet syndrome, polyneuropathy and post-herpetic neuralgia are ruled out first. That takes history, exam, a nerve study, and — when the picture is stocking-glove and on both sides — metabolic lab work including a fasting insulin. No needle is opened until that is done.

Second, do the block under ultrasound and prove it. Horner syndrome, conjunctival injection (a red eye), and a documented change in hand temperature, recorded before and after.

Third, decide what the result means. Documented sympatholysis with unchanged pain is an answer, and it redirects care the same day. Relief confirms a sympathetic role — and starts a clock. A window that is not spent on rehab is wasted.

Here is what that looks like in practice. What follows is a composite — a picture assembled from many patients with this condition, not one person’s chart. A patient arrives months after a wrist fracture that healed cleanly on film. The bone is fine; the hand is not. It is cold, swollen, glossy, and so sensitive that a shirt cuff is too much. The arm hangs unused and the shoulder is stiffening. First block: Horner syndrome within minutes, hand temperature up several degrees, pain dropping sharply — for four days. Not forever. That window told us the sympathetic role was real, and that it was not the whole disease.

The hard part came afterward. A short series of blocks was timed so each one covered a therapy session. The point was never the injection. It was getting that hand to accept being used. The worst day was the day the therapist asked for weight through a burning palm. Between visits, we worked on the terrain that keeps a nervous system sensitized: wrecked sleep, and a fasting insulin nobody had ever checked. Nutrition moved toward whole, anti-inflammatory food. Pro-resolving lipid mediators and near-infrared light were discussed honestly: adjunctive and emerging, not standard of care.

Months later that hand does most of what a hand should do, and its color is mostly back to normal. Cold weather still bites, and probably always will. That is a real outcome, not a cure. It is a practice observation, not a trial result. Individual results vary.

Maybe your hand burns and runs cold. Or maybe your nervous system has never come down from what happened to you. Either way, bring the question to someone who will measure the answer. And whoever performs the block, ask for one thing before you leave: the temperature of that hand, before and after.

Frequently asked questions

Addresses, hours and directions are listed on our Locations page.

Key takeaways

• The stellate ganglion is the fused cervicothoracic sympathetic ganglion at the C7 transverse process. It carries no pain fibers from your hand. The idea that norepinephrine drives injured pain fibers through newly formed alpha-1 adrenergic receptors is the leading proposed explanation. It has been shown in animal models and is not proven in humans.
• The needle aims at the C6 Chassaignac tubercle, one level above the ganglion. That level keeps a margin from the vertebral artery and the top of the lung. Ultrasound shows the carotid, vertebral artery, thyroid, esophagus and longus colli, which the landmark method cannot.
• A block without documented Horner syndrome, conjunctival injection, and before-and-after hand temperature produces no information. A documented block with unchanged pain is a useful answer that should redirect care. Keep the false-negative caveats in mind: an incomplete block, and fibers of Kuntz.
• The evidence differs by condition. For pain in complex regional pain syndrome, low to very low quality evidence does not support sympathetic blockade. For post-traumatic stress, a single sham-controlled trial showed a real but modest effect. The authors framed it as worth further study as an add-on, never a replacement for trauma-focused therapy or medication.
• Serious complications are rare but documented. Both sides are never blocked in one session. Benefit lasts weeks, not years. The block is worth doing mainly when rehab is already scheduled to fill the window it opens.

This article is educational and is not a substitute for evaluation, diagnosis, or treatment by a physician. Individual results vary. Do not start, stop, or change any medication without consulting your physician. To be evaluated, request an appointment at painmd.tv, call (314) 481-5000, or text (314) 886-5902.

References

1. Rae Olmsted KL, Bartoszek M, Mulvaney S, et al. Effect of stellate ganglion block treatment on posttraumatic stress disorder symptoms: a randomized clinical trial. JAMA Psychiatry. 2020;77(2):130-138. PMID 31693083. PubMed
2. O’Connell NE, Wand BM, Gibson W, Carr DB, Birklein F, Stanton TR. Local anaesthetic sympathetic blockade for complex regional pain syndrome. Cochrane Database Syst Rev. 2016;7(7):CD004598. PMID 27467116. PubMed
3. Goel V, Patwardhan AM, Ibrahim M, Howe CL, Schultz DM, Shankar H. Complications associated with stellate ganglion nerve block: a systematic review. Reg Anesth Pain Med. 2019;44(6):669-678. PMID 30992414. PubMed

Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP — Board Certified in Anesthesiology, Pain Medicine, Interventional Pain Management, Addiction Medicine, and Obesity Medicine. Last reviewed July 2026.

Dr. Gurpreet Singh Padda, MD, MBA, MHP