The Ghost in My Shoulder Blades: How I Solved My Chronic Upper Back Pain by Uncovering a Hidden Iron Deficiency

Part I: The Diagnostic Odyssey: Chasing a Pain That Wasn’t There

For years, I was haunted.

As a medical researcher, my life is dedicated to the elegant logic of the human body, yet my own body was a source of profound, illogical frustration.

The ghost was a deep, burning ache that lived between my shoulder blades.

It wasn’t sharp or stabbing; it was a persistent, draining presence that no amount of stretching, rest, or willpower could exorcise.

It was a professional humiliation.

I could decipher complex biochemical pathways on paper but couldn’t solve the chronic pain in my own trapezius and rhomboid muscles.

My journey through the healthcare system was a tour of well-meaning but ultimately fruitless interventions.

I became a case study in the standard of care for non-specific upper back pain.¹

First, there was physical therapy.

I diligently performed my prescribed exercises: scapular squeezes, rows, and thoracic extensions meant to strengthen the supposedly weak postural muscles of my upper back.³

The pain would subside for a few hours, only to return with a vengeance.

Next came chiropractic care.

I lay on the table, week after week, for spinal manipulations intended to correct subtle misalignments in my thoracic spine.⁵

The satisfying crack of an adjustment brought a fleeting sense of release, but the underlying ache remained, a low hum beneath the noise.

I tried deep tissue massage, where therapists dug their elbows into what they identified as stubborn trigger points in my back muscles.⁷

The “good pain” of the massage was a welcome distraction, but the ghost always returned by morning.

I consumed a steady diet of over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, which barely touched the pain.⁹

Like so many patients with enigmatic symptoms, mine were often attributed to stress or long hours spent hunched over a microscope and computer.¹⁰

“It’s probably just your posture,” was the common refrain.

But something felt profoundly wrong.

This wasn’t the simple muscular fatigue I knew from a hard workout; this was a deeper, more systemic sense of distress.

After a particularly rigorous and expensive course of manual therapy failed to provide lasting relief, I hit a wall.

Lying awake one night, the familiar burning sensation radiating from my spine, I was forced to ask a radical question: What if the pain in my back wasn’t the

problem? What if it was just a distress signal from a system in crisis?

This question marked the beginning of the end of my suffering.

The conventional approach, which treats localized pain with localized therapies, had failed me.

This failure itself was a crucial diagnostic clue.

The persistence of my pain, despite receiving all the “correct” local treatments, was a powerful signal that the root cause was not mechanical or musculoskeletal.

It was a sign that I needed to stop examining the individual trees and start looking at the entire forest.

Part II: The Epiphany: Viewing the Body as a Supply Chain

The breakthrough didn’t come from a medical journal or a clinical trial.

It came, unexpectedly, from an article I was reading on business logistics.

As I read about the intricate processes of supply chain management—sourcing, production, distribution, inventory—a new mental model began to form in my mind, one that would change how I viewed my own body forever.¹²

I realized the human body operates like a vast, complex corporation with an incredibly sophisticated supply chain.

• Raw Materials: These are the nutrients, minerals, and oxygen we take in from our environment.¹⁴
• Factories: These are our organs and muscle groups, each with specific jobs and production needs. The muscles of the upper back, for example, are a factory responsible for maintaining posture and stabilizing the shoulders.
• Logistics Network: This is the bloodstream, the intricate network of highways and roads that delivers raw materials to every factory in the body.¹⁵
• Energy Currency: This is adenosine triphosphate (ATP), the energy produced within our cells that powers every single operation, from thinking to moving.
• Central Management: This is the central nervous system, which monitors all operations, anticipates needs, and coordinates the entire system.¹⁶

Within this framework, my chronic back pain was no longer a mystery.

It was a classic supply chain failure.

A shutdown or malfunction in one factory (my upper back muscles) isn’t always a problem with the machinery in that factory.

More often, it’s a sign that the supply of a critical raw material has been disrupted far up the chain.¹⁴

You can’t fix a factory suffering from a resource shortage by simply tinkering with its machines or telling its workers to try harder.

You have to find the disruption and restore the supply line.

This cross-domain analogy was liberating.

It broke down the silos of medical specialization that had kept me trapped.

My problem wasn’t just a “musculoskeletal issue” for a physical therapist or a “stress issue” for a psychologist.

It was a systemic problem that required a systemic investigation.

My back pain wasn’t the disease; it was the alarm bell signaling a critical shortage somewhere in my body’s economy.

Part III: The Supply Chain Crisis: Unpacking Iron, Ferritin, and the Energy Meltdown

Armed with my new supply chain paradigm, I became a forensic accountant of my own physiology.

I pulled up years of my own health records, searching for a missing raw material.

I wasn’t anemic; my hemoglobin levels on every standard blood test were perfectly normal.

Then I saw it—a single data point on an old lab report, overlooked and dismissed: a serum ferritin level that was on the low end of the “normal” range.

This was the clue everyone, including me, had missed.

Ferritin vs. Hemoglobin: The Warehouse vs. The Delivery Trucks

To understand why this was so critical, you have to understand the difference between ferritin and hemoglobin.

Think of it in supply chain terms:

• Hemoglobin is the iron contained within your red blood cells. These are the delivery trucks on the road, actively transporting oxygen to your tissues and factories.¹⁷ A standard Complete Blood Count (CBC) measures hemoglobin, which is like counting the trucks on the highway.
• Ferritin is the body’s primary iron storage protein. It’s the iron held in reserve, mostly in the liver and inside your cells. This is the central warehouse.¹⁹

Having normal hemoglobin but low ferritin is like seeing a normal number of delivery trucks on the road but not realizing the central warehouse that supplies them is almost empty.

The system appears to be functioning, but it’s operating on fumes and is on the verge of a catastrophic collapse.

This is why a standard CBC can completely miss the impending crisis of iron deficiency.²²

This depletion happens in predictable stages, like a business slowly going bankrupt ²⁴:

1. Stage 1: Iron Depletion. The warehouse starts to empty. Serum ferritin levels drop, but the delivery trucks (hemoglobin) are still fully supplied. This stage is silent, with no obvious symptoms.
2. Stage 2: Iron-Deficient Erythropoiesis. The warehouse is now empty. The body can no longer produce fully supplied delivery trucks. It starts sending out red blood cells with less hemoglobin. At this stage, you are not yet clinically “anemic,” but the system is under strain. This is where a host of mysterious symptoms—fatigue, muscle pain, brain fog—begin to appear.²⁴ This is where I had been living for years.
3. Stage 3: Iron-Deficiency Anemia. The system fails. There are not enough functional delivery trucks to meet the body’s oxygen demands. Hemoglobin levels drop below the normal range, and all symptoms become severe.¹⁷

The Ripple Effect: When the Whole Company Suffers

This “raw material” shortage of iron doesn’t just affect oxygen delivery.

Iron is a critical cofactor for hundreds of enzymes and processes throughout the body.

When the warehouse is empty, the entire company begins to suffer in predictable ways:

• Hair Loss: The body, in a desperate act of triage, begins to “borrow” ferritin from non-essential systems, like hair follicles, to keep vital organs running. This is why hair thinning is a classic sign of low ferritin.²⁰
• Restless Legs Syndrome (RLS): This neurological disorder is strongly linked to low iron levels in the brain. Iron is essential for the production of the neurotransmitter dopamine, and a deficiency can disrupt this pathway, causing the irresistible urge to move the legs.²⁷
• Cognitive Fog, Anxiety, and Depression: The brain is an energy-hungry organ. Iron is vital for brain energy metabolism and the synthesis of key neurotransmitters like serotonin and dopamine that regulate mood.³⁰ Low iron levels are directly associated with poorer cognitive performance, irritability, and mood disorders.³²
• Classic Signs: Other well-known but often disconnected symptoms like brittle nails, intense cravings for non-food items like ice (pica), and constantly feeling cold are all distress signals from a body struggling with a fundamental resource crisis.³⁴

This understanding reframes the entire diagnostic process.

Hemoglobin is a lagging indicator of health; by the time it drops, the body has already been in a state of severe crisis for months or even years.

Ferritin, however, is a leading indicator.

It is the early warning system, the inventory report that signals an impending supply chain collapse long before deliveries stop.

The so-called “atypical” symptoms are not random; they are the predictable early consequences of this collapse.

Monitoring ferritin is proactive risk management; waiting for anemia is reactive crisis control.

Part IV: The Factory Shutdown: The Specific Reason Low Iron Targets the Upper Back

This systemic view explained my fatigue, my occasional irritability, and why I always felt cold.

But it still didn’t fully answer the central question: why was the pain so specifically and relentlessly located between my shoulder blades? The final piece of the puzzle fell into place when I connected the systemic energy crisis of low iron with the unique physiology of the upper back muscles.

My back wasn’t a random target; it was the factory most vulnerable to this specific supply shortage.

The muscles of the upper back—the trapezius, the rhomboids, the erector spinae—are not designed for explosive power.

Their primary job is postural endurance: holding your head up, keeping your shoulders back, and stabilizing your spine for hours on end.¹⁰

This requires a constant, steady supply of energy.

This is where the first vulnerability appears: the energy crisis.

The most efficient way for muscles to produce energy is through a process called oxidative metabolism, which requires a steady supply of oxygen.

Iron is an indispensable component of the mitochondria and the cytochrome enzymes that make this process possible.37 When iron is low, this efficient energy pathway is crippled.

Muscles are forced to rely on a far less efficient backup system called glycolysis, which doesn’t require oxygen but produces lactic acid as a byproduct.

This buildup of lactic acid causes the familiar burning sensation, fatigue, cramps, and deep ache of myalgia.22 Critically, research shows that postural muscles, like the dorsal muscles of the back, are particularly rich in the type of muscle fibers that rely heavily on this iron-dependent oxidative pathway, making them exquisitely sensitive to an iron shortage.37

This metabolic weakness is then compounded by a second insult: the postural collapse.

The profound fatigue and muscle weakness caused by systemic iron deficiency are well-documented.17 When you are chronically exhausted, your posture inevitably suffers.

Your head drifts forward, your shoulders round, and you begin to slouch.10 This isn’t just a bad habit; recent studies have scientifically linked iron deficiency anemia directly to “postural control disorders”.41 This poor posture places a constant, increased mechanical load on the very upper back muscles that are already metabolically compromised and starved for energy.

This creates a devastating, self-reinforcing vicious cycle.

The muscles are metabolically weak and cannot produce enough energy, and at the same time, they are mechanically overloaded and forced to do more work than ever before.

The metabolic crisis leads to fatigue, which causes postural collapse, which in turn increases the mechanical strain and energy demand on the already weakened muscles, deepening the metabolic crisis.

This “Metabolic-Mechanical Vicious Cycle” was the ghost in my shoulder blades.

It perfectly explained the persistent, burning nature of the pain and why treatments that only addressed one half of the cycle—the mechanical strain—were doomed to fail.

To solve the problem, I had to break both parts of the loop.

Part V: Restoring the Supply Chain: A Holistic Blueprint for Recovery

My path to recovery was a two-pronged attack on the vicious cycle.

I had to aggressively restore my body’s iron supply while simultaneously providing gentle, restorative care to the overworked and underfunded factory of my upper back.

A. Accurate Inventory Check: Getting the Right Diagnosis

The first and most critical step is getting the right test.

I learned to advocate for myself and now urge others to do the same: ask your doctor specifically for a serum ferritin test alongside a standard CBC.¹⁹

Understanding the results is also key.

While the “normal” lab range for ferritin can be as wide as 15-150 ng/mL, this doesn’t reflect optimal function.

Many researchers and functional medicine practitioners observe symptoms appearing when levels fall below 50 ng/mL, and clinical guidelines for conditions like Restless Legs Syndrome recommend starting treatment when ferritin is below 100 mcg/L.¹⁹

My own level was 22 ng/mL—technically “normal,” but functionally deficient.

B. Emergency Resupply: A Guide to Iron Supplementation

Once a deficiency is confirmed, the next step is restocking the warehouse.

However, not all iron supplements are created equal.

The most common prescription, ferrous sulfate, is effective but notorious for causing gastrointestinal side effects like constipation and nausea, leading many people to stop taking it.⁴³

Choosing the right form is crucial for success.

Table 1: A Practical Comparison of Oral Iron Supplements

Iron Form

Ferrous Sulfate

Ferrous Gluconate

Ferrous Fumarate

Ferrous Bisglycinate

Heme Iron Polypeptide

For severe deficiencies or for those who cannot tolerate any oral supplements, intravenous (IV) iron infusions can be a rapid and highly effective way to replenish stores, as seen in some patient stories.¹¹

C. Optimizing Logistics: Enhancing Absorption and Avoiding Disruptors

Taking an iron supplement is only half the battle.

You have to ensure it gets absorbed and delivered where it’s needed.

Using the supply chain analogy, you need a good support crew and must watch out for saboteurs.

• The Support Crew (Enhancers):

• Vitamin C: This is the most critical co-factor. It can dramatically increase the absorption of non-heme (plant-based) iron.⁴⁶ Taking your iron supplement with a glass of orange juice or a vitamin C capsule is a simple, powerful strategy.
• Vitamin A & Beta-Carotene: These nutrients help mobilize iron from storage sites, making it available for use by the body.⁴⁶ Carrots, sweet potatoes, and spinach are excellent sources.
• B Vitamins: Riboflavin (B2) and biotin play important supporting roles in iron metabolism and the formation of healthy red blood cells.⁴⁸
• The Saboteurs (Inhibitors):

• Polyphenols: Found in tea and coffee, these compounds bind to iron and prevent its absorption. You must separate your coffee or tea consumption from iron-rich meals and supplements by at least two hours.³⁹
• Calcium: Found in dairy products, calcium competes with iron for the same absorption pathways in the gut. Avoid taking iron supplements with milk or yogurt.⁴⁶
• Phytates: These compounds, found in whole grains, nuts, and legumes, can also reduce iron absorption.⁴⁶

D. Rebooting the Factory Floor: Gentle Rehabilitation for the Upper Back

While restoring the iron supply, the muscles themselves need gentle care to break the mechanical side of the vicious cycle.

The goal is not aggressive strengthening, but rather mobility, activation, and release of chronic tension.

Table 2: The Upper Back Recovery Protocol

Exercise

Scapular Squeeze

Thoracic Extension (over chair)

Standing Chest Stretch

Open Books

Part VI: Conclusion: From Systemic Ignorance to Systemic Wisdom

My personal story has a quiet but happy ending.

The ghost in my shoulder blades didn’t vanish after a particularly good stretch or a forceful chiropractic adjustment.

It faded away slowly, almost imperceptibly, over the course of three months of dedicated iron supplementation.

As my ferritin levels climbed from a meager 22 ng/mL to a robust 85 ng/mL, the chronic, burning ache that had plagued me for years simply disappeared.

The factory had come back online because its supply chain was finally restored.

The “Body as a Supply Chain” model taught me a lesson more profound than any I had learned from a textbook.

It taught me to listen to my body’s symptoms not as isolated malfunctions, but as messages from an integrated, interconnected system.

A localized pain can be a cry for help from a system in crisis.

If you are struggling with persistent, unexplained pain that defies conventional treatment, I urge you to think systemically.

Look beyond the site of your pain.

Consider the possibility of a hidden nutritional deficiency or a systemic imbalance.

Be your own advocate.

Ask your doctor for the right tests, and don’t be satisfied with a diagnosis of “stress” if you feel something deeper is wrong.

The journey from chronic pain to understanding is possible.

It begins when we stop focusing on the alarm bell and start investigating the health of the entire system.

Works cited

1. Upper and Middle Back Pain Information & Treatment – Columbia Doctors, accessed on August 10, 2025, https://www.columbiadoctors.org/health-library/condition/upper-middle-back-pain/
2. Upper back pain (thoracic pain) – Healthdirect, accessed on August 10, 2025, https://www.healthdirect.gov.au/upper-back-thoracic-pain
3. Upper Back Strain Rehabilitation Exercises | Advanced Sports & Spine, accessed on August 10, 2025, https://www.advancedsportsandspine.com/exercises/upper-back-strain/
4. Neck, Back and Spine Pain Physical Therapy | University of Maryland Medical System, accessed on August 10, 2025, https://www.umms.org/health-services/rehabilitation/services/neck-back-spine-pain
5. Should You See a Chiropractor for Back Pain? – Duke Health, accessed on August 10, 2025, https://www.dukehealth.org/blog/should-you-see-chiropractor-back-pain
6. When to See a Chiropractor for Upper Back Pain Treatment – Chiropractic BioPhysics, accessed on August 10, 2025, https://idealspine.com/when-to-see-a-chiropractor-for-upper-back-pain-treatment/
7. Upper Back Massage – Massage For Body Parts – Massage – Treatments – Physio.co.uk, accessed on August 10, 2025, https://www.physio.co.uk/treatments/massage/massage-for-body-parts/upper-back-massage.php
8. Massage for Upper Back Pain, accessed on August 10, 2025, https://bestperformancemt.massagetherapy.com/massage-for-upper-back-pain
9. Which Pain Reliever Is Best for Back Pain? – GoodRx, accessed on August 10, 2025, https://www.goodrx.com/conditions/pain/best-pain-reliever-for-back-pain
10. Identify and Treat Upper Back Pain: A Comprehensive Guide, accessed on August 10, 2025, https://www.ljchiropractic.com/blog/identify-and-treat-upper-back-pain-a-comprehensive-guide
11. My Story: Elena – CSL, accessed on August 10, 2025, https://www.csl.com/patients-public-health/iron-deficiency/iron-deficiency-patient-stories/iron-deficiency-elena
12. What Is Supply Chain Logistics? – IBM, accessed on August 10, 2025, https://www.ibm.com/think/topics/supply-chain-logistics
13. Supply Chain Management (SCM): How It Works & Why It’s Important – Investopedia, accessed on August 10, 2025, https://www.investopedia.com/terms/s/scm.asp
14. Logistics Management 101: A Beginner’s Guide | Flex, accessed on August 10, 2025, https://flexlogistics.com/news/logistics-management-101-a-beginners-guide
15. Electricity Explained: How Electricity is Delivered to Consumers – EIA, accessed on August 10, 2025, https://www.eia.gov/energyexplained/electricity/delivery-to-consumers.php
16. A Beginner’s Guide to Supply Chain & Logistics Management – BR Williams Trucking, accessed on August 10, 2025, https://brwnow.com/blog/beginners-guide-supply-chain-logistics/
17. Iron deficiency anemia – Symptoms & causes – Mayo Clinic, accessed on August 10, 2025, https://www.mayoclinic.org/diseases-conditions/iron-deficiency-anemia/symptoms-causes/syc-20355034
18. Iron-Deficiency Anemia: Symptoms, Causes & Treatment – Cleveland Clinic, accessed on August 10, 2025, https://my.clevelandclinic.org/health/diseases/22824-iron-deficiency-anemia
19. Understanding the Relationship Between Iron and Restless Legs Syndrome, accessed on August 10, 2025, https://www.rls.org/file/member-publications/handouts/Iron-2022.pdf
20. Do Low Ferritin Levels Cause Hair Loss? – Healthline, accessed on August 10, 2025, https://www.healthline.com/health/ferritin-and-hair-loss
21. Can Low Ferritin (Iron Storage Protein) Cause Hair Loss? – Vinmec, accessed on August 10, 2025, https://www.vinmec.com/eng/blog/do-low-levels-of-ferritin-iron-storage-protein-cause-hair-loss-en
22. Anemia and Muscle Pain: Why This Happens and What You Can Do …, accessed on August 10, 2025, https://www.insidetracker.com/a/articles/anemia-and-muscle-pain-why-this-happens-and-what-you-can-do
23. Low iron / anemia : r/AskWomenOver30 – Reddit, accessed on August 10, 2025, https://www.reddit.com/r/AskWomenOver30/comments/tuxiif/low_iron_anemia/
24. Iron and iron deficiency | Better Health Channel, accessed on August 10, 2025, https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/iron
25. Iron deficiency and cognitive functions – PMC – PubMed Central, accessed on August 10, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC4235202/
26. Can Low Iron Levels Lead to Hair Loss? – GoodRx, accessed on August 10, 2025, https://www.goodrx.com/conditions/hair-loss/can-iron-deficiency-cause-hair-loss
27. Restless Legs Syndrome: How to Fight a Condition That’s Stealing, accessed on August 10, 2025, https://www.muhealth.org/our-stories/restless-legs-syndrome-how-fight-condition-thats-stealing-your-sleep
28. The Link Between an Iron Deficiency and Restless Legs Syndrome – Vascular & Interventional Associates, accessed on August 10, 2025, https://www.viaveincenter.com/blog/the-link-between-an-iron-deficiency-and-restless-legs-syndrome
29. Iron in Restless Legs Syndrome – PMC – PubMed Central, accessed on August 10, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC6183309/
30. 7 Sneaky Signs You Could Have Iron Deficiency – EatingWell, accessed on August 10, 2025, https://www.eatingwell.com/sneaky-signs-of-iron-deficiency-anemia-11775333
31. Could low iron make mental health symptoms worse? – Michigan Medicine, accessed on August 10, 2025, https://www.michiganmedicine.org/health-lab/could-low-iron-make-mental-health-symptoms-worse
32. Lower serum ferritin levels are associated with worse cognitive performance in aging, accessed on August 10, 2025, https://pubmed.ncbi.nlm.nih.gov/38368845/
33. Iron deficiency, cognition, mental health and fatigue in women of childbearing age: a systematic review | Journal of Nutritional Science – Cambridge University Press, accessed on August 10, 2025, https://www.cambridge.org/core/journals/journal-of-nutritional-science/article/iron-deficiency-cognition-mental-health-and-fatigue-in-women-of-childbearing-age-a-systematic-review/3026A1A86EB9A764EEFC72E7179B7619
34. 5 symptoms of an iron deficiency – Piedmont Healthcare, accessed on August 10, 2025, https://www.piedmont.org/living-real-change/5-symptoms-of-an-iron-deficiency
35. 12 Surprising Symptoms of Low Iron – St. Vincent’s Medical Center, accessed on August 10, 2025, https://stvincents.org/about-us/news-press/news-detail?articleId=53821&publicid=745
36. Trapezius Myalgia – Physiopedia, accessed on August 10, 2025, https://www.physio-pedia.com/Trapezius_Myalgia
37. Iron deficiency as energetic insult to skeletal muscle in chronic …, accessed on August 10, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC6204587/
38. Frequency of Anaemia in Patients with Musculoskeletal Pain – ResearchGate, accessed on August 10, 2025, https://www.researchgate.net/publication/343947747_Frequency_of_Anaemia_in_Patients_with_Musculoskeletal_Pain
39. Can Anemia Cause Body Aches? Understanding the Link to Muscle and Joint Pain, accessed on August 10, 2025, https://mitohealth.com/blog/can-anemia-cause-body-aches-understanding-the-link-to-muscle-and-joint-pain
40. How to Alleviate Upper Back Pain: Quick and Effective Tips | Ochsner Health, accessed on August 10, 2025, https://blog.ochsner.org/articles/upper-back-pain/
41. Iron deficiency anemia induces postural control disorders in young women – ResearchGate, accessed on August 10, 2025, https://www.researchgate.net/publication/354802893_Iron_deficiency_anemia_induces_postural_control_disorders_in_young_women
42. Iron deficiency anemia induces postural control disorders in young women – PubMed, accessed on August 10, 2025, https://pubmed.ncbi.nlm.nih.gov/34597961/
43. Categories of Oral Iron – SABM, accessed on August 10, 2025, https://www.sabm.org/categories-of-oral-iron
44. Iron Supplements for Anemia (Ferrous Sulfate): Benefits – Cleveland Clinic, accessed on August 10, 2025, https://my.clevelandclinic.org/health/drugs/14568-iron-oral-supplements-for-anemia
45. How do different iron forms compare? – Examine.com, accessed on August 10, 2025, https://examine.com/faq/how-do-different-iron-forms-compare/
46. How to Increase the Absorption of Iron from Foods – Healthline, accessed on August 10, 2025, https://www.healthline.com/nutrition/increase-iron-absorption
47. Understanding Co-Factors and Nutrient Absorption: How Organ Meats Opti – Pluck, accessed on August 10, 2025, https://eatpluck.com/blogs/articles/understanding-co-factors-and-nutrient-absorption-how-organ-meats-optimize-nutrient-bioavailability
48. Optimal Iron – Seeking Health, accessed on August 10, 2025, https://www.seekinghealth.com/products/optimal-iron
49. Exercise Program for Upper Back Pain | Saint Luke’s Health System, accessed on August 10, 2025, https://www.saintlukeskc.org/health-library/exercise-program-upper-back-pain
50. 6 Best Upper Back Stretches Recommended for Pain Relief – Hinge Health, accessed on August 10, 2025, https://www.hingehealth.com/resources/articles/upper-back-stretches/