Understanding Referred Pain & Pain Memories: Why Pain Isn’t Always Where You Feel It

Visceral referred pain

When you feel pain, it’s natural to assume the source is right where it hurts. But the human nervous system is far more complex. Pain often appears in areas distant from the actual problem — a phenomenon called referred pain. Understanding this is essential not only for clinicians but also for anyone experiencing persistent or confusing discomfort.

At The Flow Clinic, we help clients move beyond a surface-level view of pain by exploring how the nervous system processes and sometimes misremembers painful experiences.

Why Pain Can Be “Referred”

Referred pain happens because of the way the brain receives information from deep structures like muscles, ligaments, joints, and internal organs. These tissues have poorly defined sensory maps compared to the skin. While a small cut on your finger is precisely localized, the brain struggles to pinpoint deeper pain (Kanji et al., 2005).

This is explained by the convergent theory of referred pain — signals from deep structures and signals from the skin meet (“converge”) in the spinal cord before traveling to the brain. The brain can’t easily tell them apart, so it projects deep pain onto a more familiar and clearly mapped area of the body (Kanji et al., 2005; Gifford, 1998).

That’s why an irritated lumbar facet joint in the spine can cause pain in the buttock or thigh, or why issues in the sacrotuberous ligament can radiate elsewhere (Grieve’s Modern Manual Therapy).

The Blueprint of Pain: Dermatomes, Myotomes, Sclerotomes

Our body’s tissues come from distinct embryological segments called somites — which form skin (dermatomes), muscles (myotomes), and bones/ligaments (sclerotomes). Each carries its own nerve supply from specific spinal levels. When these nerves are irritated or overloaded, pain can be felt far from the actual problem site.

For example:

• Hip joint issues can refer pain to the knee (sclerotomal referral).

• Lumbar spine irritation can send signals into the leg, sometimes mimicking sciatica.

Nociceptive, Neuropathic & Central Sensitisation: The Three Key Mechanisms

Pain isn’t all the same. Understanding which mechanism is driving it can guide better treatment.

• Nociceptive pain — triggered by tissue injury (sprain, strain, inflammation). It’s usually localized but can follow predictable referral patterns (Beith et al., 2011).

  
  

• Neuropathic pain — caused by nerve irritation or compression (think “shooting” or “burning” pain). This includes radicular pain, which travels along the nerve’s path, but differs from radiculopathy, where there’s also loss of function (numbness, weakness) (Beith et al., 2011).

  
  

• Central sensitisation — when the nervous system becomes hypersensitive after prolonged or intense input. Even after the original injury heals, the spinal cord and brain may remain “turned up,” lowering pain thresholds and causing previously non-painful stimuli to hurt (Gifford, 1998).

When Pain Lingers: The Science of Pain Memories

Perhaps the most fascinating — and frustrating — concept is pain memory. If pain has been severe or long-lasting, the nervous system can “remember” it. Neural pathways retain a record of the experience, including the emotions, movements, and protective behaviors linked to that pain (Gifford, 1998).

This means:

• A healed injury can still hurt if the nervous system is sensitized.

• Emotional stress or illness can “re-trigger” pain in the absence of new tissue damage.

• Patients may unconsciously protect or avoid using a previously painful area.

In some cases, even non-painful inputs like immune challenges (e.g., a viral infection) or re-experiencing a stressful event can bring back old pain sensations (Gifford, 1998).

Why This Matters for Recovery

For clients at The Flow Clinic, this science shapes our approach:

• Precise assessment — We look beyond where it hurts to uncover the actual source of nociceptive or neuropathic input.

• Neuro-informed treatment — Combining manual therapy with movement retraining to calm sensitized pathways and restore confidence.

• Education & self-awareness — Understanding pain mechanisms helps break the fear-pain cycle and reduces the brain’s tendency to “protect” unnecessarily.

Takeaway

Pain is a complex, protective signal — but not always a reliable map of injury. If you’re experiencing persistent or spreading discomfort, it doesn’t mean there’s always something new “wrong.” Sometimes, the nervous system itself needs recalibration.

References

• Beith, I. D., Kemp, A., Kenyon, J., Prout, M., & Chesterton, L. S. (2011). Identifying neuropathic back and leg pain: a cross-sectional study. Pain, 152(7), 1511–1518.

• Gifford, L. (1998). Pain, the tissues and the nervous system: a conceptual model. Physiotherapy, 84(1), 27–36.

• Gifford, L. (1998). Topical Issues in Pain 1: Whiplash — Science and Management. CNS Press Falmouth.

• Kanji, N., et al. (2005). Convergent referred pain mechanisms: The research and implications for clinical practice. Australasian Musculoskeletal Medicine, 10(1).

• Grieve, G. P. (2015). Modern Manual Therapy: The Vertebral Column. Elsevier.