When the tests are normal but it still hurts — I look at the tissue's environment, not the structure

The tests are normal, but it still hurts.

There is hardly a day in the clinic when I do not hear this. The imaging shows nothing wrong, the blood work is clean, and yet the patient clearly hurts.

At times like this I move where I am looking. Not to where the bone sits, but to what state the tissue beside it is in right now.

The structure is normal; the tissue is not

This is not a feeling. It has been measured.

There is a study that looked at the lower backs of 107 people with chronic low back pain using ultrasound. The connective tissue beside the muscle came out roughly 25% higher in thickness and density. What is interesting is that the change was gathered right beside the muscle, not in the fat layer under the skin.

The same group confirmed it again in 121 people. This time what they measured was how well layer slid against layer. On the painful side, that sliding was reduced by about 20%.

This is why the imaging comes back normal. The bone is fine. What has changed is the tissue that ought to be sliding and stretching beside it, and today's imaging does not show that well.

That said, what these studies showed is that the two appear together — not which came first. Whether the tissue stiffened and then it hurt, or it hurt and so moved less and then stiffened, is left open by the researchers who wrote the papers.

The place that hurts and the place with the cause can differ

This too has been confirmed in people.

There is a study in which an acidic solution was injected into the shin muscle of 72 healthy volunteers. That the injected spot hurts is obvious. But pain also appeared at the ankle, some distance away — in 80% of the women and 40% of the men.

This is not a metaphor; it is a phenomenon induced by experiment. So I do not look only at the spot you tell me hurts. Sometimes a person comes in with calf pain and the answer is not in the calf, and then I trace upward.

A specific route from one place to another is not something I can lay out with evidence in hand. That pain can arise at a distance is what has been confirmed; beyond that is territory I search with my hands.

Leave it still and it grows stiff

Here thixotropy enters — a concept I have held onto for a long time.

Some substances sit stiff when left alone and turn loose when shaken. Ketchup is like that. In the bottle it is set; shake it and it flows.

Muscle genuinely behaves this way. Even a muscle that is slack and at rest develops resistance if left still. Move it and that resistance falls; rest again and it rises.

The mechanism is known too. Even inside a relaxed muscle, actin and myosin keep binding a little, spontaneously. These are not force-producing bonds, just bonds sitting there, and they create the stiffness. Move, and they come off; stop, and they re-form at the new length.

There is a study that confirmed this directly in people. In the wrists of twelve volunteers, shaking or applying vibration dropped the muscle's initial resistance by about 19–20%.

So I do not work by force — and it does come back

What has stiffened does not have to be overcome by force. There is a path along which it softens on its own, and that is the path I take.

But this property has a far side: it comes back. Like the ketchup setting again once you stop shaking. In that same wrist study, after about 15 seconds of rest, most of the stiffness had returned.

I cannot hide that and say "release it once and it never comes back." Nor do I need to. It is precisely the coming back that explains why one session does not finish the job, and why you need to move in between. (When the correction keeps coming undone — maintenance is half the treatment)

Tissue with a tendency to stiffen keeps trying to stiffen. So treatment is not a single event but the work of changing a direction.

What Korean medicine has long said

Korean medicine has long spoken of blocked places, stagnant places, places where heat has gathered.

I do not read these words only as metaphor.

The old language	How I read it
Blocked	Tissue where layer does not slide against layer
Stagnant	Tissue where flow has stalled and conditions differ from the surroundings
Heat has gathered	Tissue where inflammation continues and the chemical environment has changed

To what the ancients read with their fingertips, names are being attached one by one. So I do not look only at the imaging — I lay on a hand. Whether it is stiff or soft, whether it slides or sticks, whether there is heat or rather cold — for someone whose tests are normal, a good share of the remaining information sits here.

What this article dealt with is one axis, the physical one, among the several the body has. Chemistry, metabolism, immunity stand alongside it, and none of them plays the boss. It is only that among people who come to me with pain, I often find this axis tilted first. (What herbal medicine does)

There are fractures, there are tumors, there are infections. When such a signal shows, I recommend testing first.

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Not visible does not mean not there.

It only has to be read in a different language — and that language is beginning to have numbers attached to it.

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Sources

• In 121 people with chronic low back pain, sliding between fascial layers was reduced by about 20% — BMC Musculoskeletal Disorders, 2011
• Injecting an acidic solution into muscle produced pain not only at that spot but at the ankle some distance away — Pain, 2008
• Human muscle stiffens when left still and softens when shaken, and the stiffness returns with rest — The Journal of Physiology, 2001

Written by Dr. Heo Ji-young (PhD in Korean Medicine Pathology, Kyung Hee University · former Research Professor of Herbology, Kyung Hee University)