Referred Pain 101: Why Shoulder Pain Isn't Always a Shoulder Problem
Referred Pain 101: Why Your Shoulder Pain Might Not Be a Shoulder Problem
Quick summary
- Referred pain happens when nerve signals from two different areas effectively "cross wires" in the spinal cord — a mechanism called convergence — causing pain to be felt somewhere other than its true source (Jin et al., 2023).
- Heart-related pain doesn't always show up as chest pain: roughly a third of people with a confirmed heart attack have no chest pain at all, and shoulder or arm pain is actually twice as strong a predictor of a heart attack in women as it is in men (McGaw, 2026).
- Older adults, women, and people with diabetes, high blood pressure, heart failure, or a prior stroke are more likely to have these atypical, non-chest-pain presentations — and atypical presentations are linked to delayed diagnosis and worse outcomes (McGaw, 2026).
- Musculoskeletal referred pain is also common and usually far less urgent — a problem within the spine itself can genuinely refer pain into the shoulder, buttock, or leg, which is where a proper assessment can help trace symptoms back to their real source.
When to seek urgent medical care
New or unexplained shoulder, arm, jaw, or upper back pain — especially if it's sudden, comes with chest discomfort, shortness of breath, nausea, sweating, dizziness, or fatigue, or appears alongside risk factors like diabetes, high blood pressure, or being an older adult — should be treated as a possible medical emergency. Call 000 or go to your nearest emergency department. This is not something to wait out or address with musculoskeletal treatment first.
It's a genuinely strange feature of how the nervous system is wired: pain can be felt in a place that has nothing structurally wrong with it, while the actual problem is somewhere else entirely. This is called referred pain, and understanding roughly how it works helps explain why some symptoms need urgent medical attention while others are perfectly appropriate for a musculoskeletal assessment.
How Referred Pain Actually Works
The leading explanation is known as convergence: nerve fibres carrying pain signals from an internal organ or deep structure, and nerve fibres carrying signals from a specific area of skin or muscle, both funnel into the same neurons in the spinal cord. The brain, receiving a mixed signal, can misattribute where the pain is actually coming from — sometimes described as "crossed telephone lines." Related mechanisms involve branching nerve fibres that supply both the area of the original problem and a separate referred area, and a process called central sensitisation, where ongoing pain signals can "open" additional nerve connections that weren't initially carrying pain information, amplifying and spreading the sensation (Jin et al., 2023).
When Shoulder or Arm Pain Is a Medical Emergency, Not a Shoulder Problem
The clearest, highest-stakes example of referred pain is cardiac: heart-related chest pain can refer into the shoulder, arm, or jaw. More importantly, a genuinely significant number of people having a heart attack don't experience classic chest pain at all. Research shows approximately one-third of patients with a confirmed heart attack present without chest pain, and shoulder or arm pain specifically is twice as strong a predictor of acute coronary syndrome in women compared to men. Other non-chest-pain presentations include jaw pain, upper abdominal discomfort, shortness of breath, nausea, and fatigue — and in older patients, even confusion or fainting. These atypical presentations are more common in older adults, women, and people with diabetes, high blood pressure, heart failure, or a history of stroke, and are associated with delays in diagnosis and worse outcomes, precisely because the pain doesn't point where everyone expects it to (McGaw, 2026).
Musculoskeletal Referred Pain Is More Common and (Usually) Less Urgent
Most referred pain isn't cardiac. Problems originating within the spine itself are a far more common source of referred pain in everyday practice — a lumbar disc issue can refer pain into the buttock and leg, a cervical facet joint problem can refer pain into the neck and shoulder region, and sacroiliac joint dysfunction can refer into the lower back and groin (Jin et al., 2023). These presentations are generally not emergencies, but they do benefit from a proper assessment, because treating the area where the pain is felt, rather than the structure actually generating it, tends to fall short.
Practical Takeaways
- Any sudden, unexplained shoulder, arm, or jaw pain with other symptoms (chest discomfort, breathlessness, nausea, sweating, dizziness) is an emergency — call 000 or go to an emergency department, don't wait to see if it settles.
- Be extra cautious if you're an older adult, a woman, or have diabetes, high blood pressure, or heart disease risk factors — atypical presentations without chest pain are more common in these groups.
- Gradual, activity-related shoulder, back, or leg pain without those warning signs is more typically musculoskeletal — a reasonable candidate for a chiropractic or physical assessment.
- Don't assume treating the painful spot will fix the problem if the true source is somewhere else in the spine — proper assessment matters.
- When in doubt about anything resembling cardiac symptoms, seek medical care first — it is always the safer choice.
Dealing with ongoing shoulder, back, or leg pain that doesn't match a clear local injury?
Once any serious cause has been ruled out, a thorough assessment can help trace musculoskeletal referred pain back to where it's actually coming from.
Frequently Asked Questions
What is referred pain?
Referred pain is pain felt in a location different from where the actual problem is. It happens because nerve signals from different areas can converge on the same pathways in the spinal cord, causing the brain to misattribute where the pain is coming from.
Can shoulder pain be a sign of a heart attack?
Yes. Research shows roughly a third of people having a confirmed heart attack have no chest pain at all, and shoulder or arm pain is twice as strong a predictor of a heart attack in women compared to men. Sudden shoulder or arm pain with other symptoms like breathlessness, nausea, or sweating needs urgent medical assessment.
Who is more likely to have an atypical heart attack presentation without chest pain?
Older adults, women, and people with diabetes, high blood pressure, heart failure, or a history of stroke are more likely to present without classic chest pain, and these atypical presentations are linked to delayed diagnosis and worse outcomes.
Is all referred pain a medical emergency?
No. Musculoskeletal referred pain is common and usually not urgent, for example a spinal disc or joint problem referring pain into the shoulder, buttock, or leg. The key is recognising red flags, like sudden pain with chest discomfort, breathlessness, or other warning symptoms, which do need urgent medical care.
References
- Jin, Q., Chang, Y., Lu, C., Chen, L., & Wang, Y. (2023). Referred pain: Characteristics, possible mechanisms, and clinical management. Frontiers in Neurology, 14, 1104817. https://doi.org/10.3389/fneur.2023.1104817
- McGaw, S. (2026). Atypical myocardial infarction: Recognizing ACS without chest pain. Medical Student Pearl, Dalhousie University.
