PTSD and Physical Pain: Why Trauma Shows Up in the Body

There is something people with PTSD are rarely told in the consulting room. That the pain is real. Not a side effect, not attention seeking, not something that lifts once the flashbacks ease. PTSD is treated mainly as a psychological condition, and that is partly right. It is also a nervous system condition, and the physical pain that so often travels with it has a measurable physiology.

I want to show you how I look at it. Because I look at PTSD the way I look at pain: as a language. As a message from a system that went through something it could not fully process. And that language deserves translation.

Why does PTSD change the way the brain handles threat?

PTSD does not arise because someone is too sensitive. It arises because the nervous system is efficient. It learned that a situation was life threatening, and it set out to make sure you were never caught off guard again. So the system stays alert. Even when the threat is gone.

Two brain regions come up repeatedly in the imaging literature, and it is worth being precise about what each one shows, because the two findings are not equally strong.

The hippocampus, which places memories in time and context, shows the more consistent structural finding. O’Doherty and colleagues, pooling 36 volumetric studies in a systematic review and meta-analysis, found reduced hippocampal volume in PTSD, with the larger reduction on the left.⁴ When context binding is weakened, the brain separates past from present less cleanly. What happened can feel as though it is still happening.

The amygdala, which detects threat, is a subtler story, and popular accounts routinely overstate it. Structurally, the volume findings are mixed: reductions appear against healthy controls but largely disappear when the comparison group is people who experienced trauma without developing PTSD.⁴ Functionally, the picture is stronger, with amygdala hyperreactivity reported across the PTSD imaging literature, though it is not unique to PTSD and appears in other anxiety disorders too.⁵ So the honest version is this: the threat detection system in PTSD responds faster and to smaller cues, and that is a functional finding rather than a visible structural lesion.

This is not character. This is neurobiology. And neurobiology can change.

How often do PTSD and chronic pain actually occur together?

Often, though the honest answer has wide error bars, and anyone quoting a single tidy percentage is oversimplifying.

Fishbain and colleagues, in an evidence-based structured systematic review of 40 studies in Pain Medicine, found PTSD prevalence in chronic pain populations ranging from 0.69 percent in chronic low back pain up to 50.1 percent in veterans, and concluded there is consistent evidence that the two are associated.² A meta-analysis by Siqveland and colleagues in Frontiers in Psychiatry, pooling 21 studies, put the overall figure at 9.7 percent, rising to 20.5 percent in chronic widespread pain.³ That same analysis contains the caveat that matters most: PTSD prevalence was 20.4 percent in studies using self-report questionnaires and 4.5 percent in studies using structured clinical interviews. How you measure changes the answer by a factor of four.

What holds across the literature is the association, not a clean causal arrow. Pain may follow trauma, trauma may follow injury, and both may share a common vulnerability.

What is central sensitisation, and how does PTSD keep it switched on?

Central sensitisation means the nervous system has become oversensitive to input. The volume dial for pain signals sits too high. Ordinary touch can hurt. Fatigue triggers a cascade. And the pain moves around, because it is not about one specific tissue but about a system sounding an alarm everywhere at once. If you have ever been told your scans and bloodwork are normal while you clearly do not feel normal, this is often the missing mechanism, and it is the same territory we covered in when your labs are normal but you feel terrible.

Manuel, Rudolph, Beissner and colleagues examined this directly in a German university outpatient pain clinic, publishing in Psychosomatic Medicine in 2023. Patients with both chronic pain and PTSD showed a larger and more widespread pain area, together with raised anxiety, depression and somatisation, a pattern the authors describe as compatible with central sensitisation.¹ It is a single-clinic study rather than a trial, so it establishes a pattern rather than a cause.

The proposed link is straightforward: a threat response held open for years keeps muscle tone up and the pain threshold down. Not consciously. Not by choice.

Why do pain and PTSD reinforce each other?

Because they form a loop, and the loop is well characterised in the pain literature under the fear avoidance model.

Pain raises fear and vigilance. Vigilance raises attention to bodily sensation. Heightened attention makes pain more intense. More intense pain confirms the belief that something is seriously wrong, which raises the fear again. Vlaeyen and Linton’s model, reviewed at length by Leeuw and colleagues and revisited by the original authors twelve years on, describes exactly this self-reinforcing cycle of catastrophising, fear, hypervigilance and avoidance, and the deconditioning and disability that follow.⁶ ⁷ Lumley and colleagues, reviewing the emotion and pain research in the Journal of Clinical Psychology, add the other half: greater pain is associated with emotional stress and with limited emotional awareness, expression and processing.⁸

Every part feeds the next. Which is why treating pain and PTSD as two separate problems, in two separate rooms, so often fails to move either. The related question of how much of this the mind actually drives is one we took up in is stress bad for you?

How does trauma show up in muscle, breath and posture?

I see it daily. Someone walks in. Shoulders lifted. Breath high in the chest. Jaw lightly clenched. A protective posture carried so long they no longer feel it.

The body learned that making yourself small is safer, that contracting is protection, that holding every muscle is the only thing that gives a sense of grip.

The vagus nerve is usually invoked at this point, and here I want to be careful, because the popular version has run well ahead of the evidence. Porges’s polyvagal theory proposes that when the nervous system registers safety it supports recovery, growth and connection, and that chronic threat weakens that regulating capacity.⁹ It is an elegant model and it has been enormously influential in trauma work, including my own field. It is also genuinely contested. Grossman’s 2023 review in Biological Psychology challenged all five of the theory’s founding premises as inconsistent with current neurophysiological and evolutionary evidence,¹⁰ and a larger co-signed challenge followed in 2026; Porges and clinical educators have published responses. The debate is live and unresolved.

What is not in dispute is the clinical observation underneath it: chronic stress raises muscle tone, shifts breathing higher into the chest, and reduces the flexibility with which the autonomic nervous system moves between readiness and rest. You do not need to settle a theoretical argument to notice that a jaw has been clenched for a decade.

What do body-based methods actually do, and what do we know?

I am not a mental health clinician. Where I suspect PTSD, serious dissociation or significant dysregulation, I refer on to specialist care. What I do is work with the body’s own signals.

The methods I use, Body Remembers Trauma Therapy and Trauma Release Breathwork, rest on one principle: given the right conditions, the body restores itself. The first works through movements of the psoas, the deep pelvic muscle that responds to fear, generating tremor through which the system can discharge held tension without the details of the trauma needing to become conscious. The second works through specific breathing patterns intended to shift the body toward a parasympathetic state. The lineage runs back through Peter Levine’s somatic work in the 1990s and David Berceli’s tremor-based exercises.

I want to state the evidence position plainly, because you deserve it: this mechanism is proposed, not demonstrated. Neither method has been tested in controlled trials. The nearest researched relative, Berceli’s Tension and Trauma Releasing Exercises, has case reports and small preliminary studies and no robust randomised evidence. What I can honestly offer is clinical observation across many people, not proof, and it should sit alongside evidence-based trauma treatment rather than in place of it.

What I observe is consistent: as the tension lets go, the pain often eases. The neck. The back. The chest. The jaw. Not because I treated it, but because the system finally had room.

Where recovery actually starts

Talking helps. Understanding helps. But a body that has spent years braced does not usually stop bracing because it has been given an explanation. It tends to need experience: breath, movement, and the slow accumulation of evidence that now is not then.

When I describe the process I use the image of a ball pit. A pit full of balls of every size, each one an experience, a pattern, a piece of held tension. Some sit at the bottom, under everything else. The body decides the order in which it lets go. Not you, and not me. What we do is make room and follow what is offered. Force it, go for the big ones before there is enough safety, and the system closes. Safety is not the preparation for the work. Safety is the work.

So: perhaps your body is responding exactly as a body responds after what you went through. Perhaps the vigilance is not a character flaw but a protective system that once did its job. Perhaps the pain is not attention seeking but a nervous system that has been working too hard for too long.

And perhaps recovery does not begin with working harder on yourself, but with learning that it is safe now. Step by step, at the pace of your own system.

This article is educational and is not a substitute for individual medical advice. It describes practices for general understanding only. Astrela does not recommend, endorse or advise against any specific practice, product or intervention. If you are living with PTSD or suspect you may be, please seek assessment from a qualified mental health clinician. Before starting anything new, especially anything invasive or unregulated, consult a qualified clinician who knows your situation.