The Edge of the Spoon

[John W]

Hey, Jon,

What do you mean that I "may" be right?

I don't think we'll be able to change the character of the users and exploiters. They are what they are. But I think it's possible to convince those who think it's too hard to embrace the change that comes with the neurobiological revolution that it could actually make their professional lives not only more interesting and rewarding, but in many ways less difficult.

At least, that's been my experience. Once I got past being pissed off for getting gypped by my PT school, and buckled down for about a year and half and started reading about pain, I experienced a sense of freedom form the connective tissue morass that I'd become trapped in. My hands and my own nervous system felt a tremendous sense of relief from that inscrutable pile of nonsense.

The other big issue is one of demoralization on the part of many earnest, yet frustrated, health care providers. This is a health care system-wide problem that affects all providers and is running off a good many physicians, nurses and PTs.

I know some of those good, earnest PTs who wouldn't dare recommend that their kids go into this field- not the way things are now. What a shame and a waste.

[nari]

One doesn't have to know anything about the origin of a river to appreciate (or hate) its beauty and its dangers. However, to know about its origin adds to the appreciation of its effects on the land and people, and how its existence is very dependent on its origin.
The origin/s of pain are crucial to know with respect to understanding something about its management. It's different from a something like a river, but there are similarities.

There are so many people hanging out to do physiotherapy in Aust. that it is one of the few most difficult courses to get into. (One has to be in the top 2% when leaving secondary school). I'm not sure that's a good thing altogether.

Nari

[Mary C]

I used to be hard to get into physio here, too. Now the local school in Nova Scotia is complaining about the quality of recruits. Might have something to do with the lack of competitive salaries. The top in New Brunswick is 63K for 37.5 hrs/wk

[nari]

What kind of complaints are they making at the NS school? Is that due to lowered entry scores?
Our top salary (for head of a hospital department of about 35 PTs) is around 110K, and the AU$ pretty well matches the CA$...most of the time. For someone who is a supervisor of an area, say Outpatients, the salary is around $76K. No overtime is paid in excess of 37.5 hrs/wk, but days off in lieu can be accrued, as well as a set 1 day a month off on full pay.

Nari

[Mary C]

What does a rank and file PT get?

[Chancellor Mobley]

I can now say, "When the patient is complaining of pain there are four origins and two mechanisms to consider. If you know nothing of these or what they represent it isn't because neuroscience hasn't taught us - it may be because you have yet to read it. Let's begin..." Barrett Dorko

Barrett, would you mind expounding here. I've been reading a bit, yet it seems there is always more. Obviously, I could have missed something. Here is my simplistic version of what I have garnered with regards to the pain experience. I was thinking that there was one origin of pain and that that was the Nervous System. Within the origin of the N.S. I see that there are two states of reference, the central and peripheral one. Through the concert and mechanisms of these two the pain experience arises.


With regards to the mechanisms, I am less clear. Barrett, when you speak of the two mechanisms to consider are you referring to the central and peripheral nervous systems and when you speak of the four origins are you speaking of the types of nociception within the P.N.S.(mechanical, chemical,and thermal)? If yes is the answer to the later half of my question, then I am still wondering what you may be referring to as one of the four origins? Regardless, I may be confused with my understanding of 'mechanism' and how it is being used in relationship to CNS and PNS or just off the mark. For me, it seems that nociception may be better defined as a mechanism within the PNS. Any help clearing my muddy waters would be appreciated.


Chance

[EricM]

Hi Chance,
I think you'll find some answers to these questions in these two threads:
5 questions
Consensus on Pain

[Jason Silvernail]

Chance, those are good links eric posted.
Four origins - central sensitization, ectopic discharge, mechanical deformation, chemical irritation (thermal included here)
Two mechanisms- central and peripheral

Obviously overlap of these is the rule, not the exception here.

[Barrett Dorko]

I just re-read this thread and find it a wonderful example of what might be accomplished by a group of therapists devoted to learning and sharing. I think I got more than I bargained for and have had to revisit some of the links provided as well.

One question: When considering the origin of ectopic discharge and its management, is it fair to say that this will be manifest quite commonly as a tender spot, painful to palpation, likely to elicit spreading pain and often thought to be a local muscular "lesion" or dysfunction of the spindle? Do we know that it's more likely to be an abnormal impulse generating site (AIG)? Can we say that an accurate deep model includes a nervous membrane that has developed adreno-sensitive ion channels?

Also: What exactly is the difference between transduction and transmission?

I actually know some of these "edges" but also know that I can speak of them with more confidence and evidence at my fingertips if we consider all of this here. It will also provide another even more useful link for my poor future students.

[Barrett Dorko]

Hello,

This active board quickly buried this thread ad I wanted it revived in light of my recent questions.

Any takers?

[Jon Newman]

What exactly is the difference between transduction and transmission?--Barrett

I think the distinguishing feature of transduction is the conversion of one form of energy into another. Transmission is the journey that new energy form takes. Would it be correct to say that a new round of transduction occurs at each new synapse?

For more see Diane's post on the Molecular Mechanisms of Nociception

[Jason Silvernail]

One question: When considering the origin of ectopic discharge and its management, is it fair to say that this will be manifest quite commonly as a tender spot, painful to palpation, likely to elicit spreading pain and often thought to be a local muscular "lesion" or dysfunction of the spindle? Do we know that it's more likely to be an abnormal impulse generating site (AIG)? Can we say that an accurate deep model includes a nervous membrane that has developed adreno-sensitive ion channels?

I'm not sure we can necessarily connect the AIG to a tender spot, though we can definitely say with some confidence that an AIG has increased channel density making it more sensitive to stimuli (including normally non-nociceptive chemical irritation and mechanical deformation), and that it is likely to have some adreno-sensitivity as well. So the AIG would be tender if pressed and certainly would be expected to produce local as well as spreading pain sensations when it fires both orthodromically and antidromically.

Clinically, could we see of the manifestations of adrenosenstivity when the pain experience is magnified by stress or emotional state? Or might that be just as likely a central effect? Short of injecting adrenaline into the area (which is of course how this adreno-sensitivity was discovered), I'm not sure we can know, though its most certainly likely given what we now know.

The connection from the AIG to the local muscle dysfunction is harder to be sure about, it seems to me the shortest distance there is Wall's instinctive motor response toward resolution.

[Diane]

I think it is worth considering that a peripheral neuron is a continuous sensing cell from cutaneous receptive field (where its ending is buried in amongst all sorts of skin cells in the bottom layers of the epidermis which can secrete neurotransmitters to bother it) to dorsal horn (where it can be bothered by microglia). Anywhere in between it can be bothered by hypoxic conditions secondary to mechanical distortion of its vasa nervorum. It is bi-directional, so it can signal distress up or down from whatever might be a primary bother.

Lucky for us, we can get on it at least at one end, for sure. Not so much at the other.

[Barrett Dorko]

As always, wonderful help.

Perhaps we can say (given what Luke especially has provided elsewhere about trigger points) that a change in the nervous tissue that could account for the clinical findings of tenderness and bidirectional, spreading pain has been definitively demonstrated but that a change in the muscular tissue, well, not so much. Perhaps not at all. Is that fair?

This origin (one of four, remember) of ectopic discharge seems to embody elements of the other three quite readily. I don't look for it, to tell the truth, figuring that addressing the other three that accompany it in various ways will be enough in the clinic. In short, I don't poke people - and that's always a good idea.

[BB]

While it makes sense that an AIG would be more likely to be painful to palpation, all tender spots are not necessarily AIG's. Shacklock's descriptions of neurodynamic quality of neural movements tells us that mechanical strain is imparted to the nerve moreso where they turn a corner, such as at the elbow for the ulnar nerve, or at the "gromitt holes" (as Diane calls them) for cutaneous nerves. Thus, a spot tender to palpation may often be the access point to a mechanosensitive neural tissue in absence of an AIGS.

Not sure if that adds anything of value or not.