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Tissue/physical stress theory and only using 1 orthotic device
Re: Tissue/physical stress theory and only using 1 orthotic device
Great question Michael and it has been asked of me by a patient.
I responded that although only one foot is experiencing a complaint, it is important to provide a similar yet independent support to the opposite and unaffected foot for symmetrical purposes.
We do not rehab one arm when there is a biceps tear, we use two arms to conduct our lives. The eye doctor does not address only the problem eye but the pair. Orthodontists may only seek to alter the position of two adjacent teeth but typically use the entire row in the process. We walk on two feet so they should be dispensed in pairs.
Some types of AFO devices are case in point. I see iatrogenic LLI induced low back pain due to the offset in height from gauntlet AFO's because there will be a difference in height and it will affect some patients. In this case I often provide an insole, outsole addition etc. to mediate this. Especially if there is a low back history. It is the same with an FFO in many cases.
Some people here have an issue with the word symmetry, I do not. As for studies I haven't seen any. It will be interesting to see if anyone has.
regards,
__________________
"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." - Orville Wright
Re: Tissue/physical stress theory and only using 1 orthotic device
For the sake of discussions
Quote:
Originally Posted by David Wedemeyer
Great question Michael and it has been asked of me by a patient.
I responded that although only one foot is experiencing a complaint, it is important to provide a similar yet independent support to the opposite and unaffected foot for symmetrical purposes. ,
But the human body is not symmetrical, and if we a following tissue stress to the letter how do you design the device for the opposite leg ? Remember a orthotic can only move load from one tissue to the other, so if there is no stress tissue how do you decide what tissue gets the more or less stress ?
Quote:
Originally Posted by David Wedemeyer
We do not rehab one arm when there is a biceps tear, we use two arms to conduct our lives. The eye doctor does not address only the problem eye but the pair. Orthodontists may only seek to alter the position of two adjacent teeth but typically use the entire row in the process. We walk on two feet so they should be dispensed in pairs. ,
Any injury Ive had and I had tons Ive only rehab the effected muscle or ligament. Ive had 3 navicular stress fractures but only treated the effected side, ie I was placed in 1 moon boot at the time.
I also know of lots of folks who get plain glass in one eye and prescription glass in one. So yes they look the same in the frame but only one side is changing vision.
Quote:
Originally Posted by David Wedemeyer
Some types of AFO devices are case in point. I see iatrogenic LLI induced low back pain due to the offset in height from gauntlet AFO's because there will be a difference in height and it will affect some patients. In this case I often provide an insole, outsole addition etc. to mediate this. Especially if there is a low back history. It is the same with an FFO in many cases.
Some people here have an issue with the word symmetry, I do not. As for studies I haven't seen any. It will be interesting to see if anyone has.
regards,
but in the above example your using tissue stress to guide you, ie history of lower back pain or presenting symptoms.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
m weber;188658]For the sake of discussions
But the human body is not symmetrical, and if we a following tissue stress to the letter how do you design the device for the opposite leg ? Remember a orthotic can only move load from one tissue to the other, so if there is no stress tissue how do you decide what tissue gets the more or less stress ?
Symmetrical in that we have two, I agree that we are not perfectly symmetrical to the letter. Let's try this; does your car have tires from two or more different manufacturers, sizes, treads? No, I doubt it does and why? Because it affects the whole, agreed? If you place a device in the shoe of an individual, do we know the effect on the opposite foot if there is no similar device afforded? No we do not. What we are providing is a basic device (unless otherwise necessary) with a similar base characteristic; shape unique to that individual and material. You would do the same for a cars tires, wheels etc.
Quote:
Any injury Ive had and I had tons Ive only rehab the effected muscle or ligament. Ive had 3 navicular stress fractures but only treated the effected side, ie I was placed in 1 moon boot at the time.
Perhaps because FFO's are functional and improve gait and 'moon boots' impair function. Why would you increase the likelihood of altering their gait and creating iatrogenic injury by using symmetry as a guide in this case? Occam's Razor allies here no?
Quote:
I also know of lots of folks who get plain glass in one eye and prescription glass in one. So yes they look the same in the frame but only one side is changing vision.
Precisely! Cosmetic perhaps but the doctor evaluates both eyes individually as well and dispenses them as a unit, a system. Aren't the feet a system, two like organs of the same or similar function?
Quote:
but in the above example your using tissue stress to guide you, ie history of lower back pain or presenting symptoms.
lawyer for the devil...
Indeed!
__________________
"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." - Orville Wright
Re: Tissue/physical stress theory and only using 1 orthotic device
Good question.
I'd answer thus (to you).
Orthoses have a wide variety of effects. There is the intended theraputic effect, reducing the tissue stress in the affected tissue. But there is a whole swathe of other effects. The kinetic effects of the rest of the orthoses. The difference in "feeling". The neuromotor element. The difference in heel height. the difference in the amount of room in the shoes. We seek to control the desired element but we affect many other things unintentionally and If we are honest, we don't fully understand the effects of these changes.
Tissue stress is about reducing tissue stress in individual tissues to within tolerable levels. There is an element of distributing stress amoung structures. To paraphrase the communist manifesto, to each according to need, by each according to ability. If we use one insole only I would have concerns that we would create such a disparity between function on the two sides, we would create other problems. Not least by createing a LLD!
Re the moon boot, that situation is a bit different. If you have fractures the "need" of that tissue to be protected is paramount. We WANT the other side to do all the work!
If I have one side which looks straight down the line as I would want it to, and the other patholgical, I'll do a "blank" for the good side. Minimal interferance, no posting, no mods and morphology similar to the pathological side. But I think it is right that they have something in both sides to accomodate all those unknown effects.
To the patient I'd say "otherwise you'll walk in circles!"
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by David Wedemeyer
Symmetrical in that we have two, I agree that we are not perfectly symmetrical to the letter. Let's try this; does your car have tires from two or more different manufacturers, sizes, treads? No, I doubt it does and why? Because it affects the whole, agreed? If you place a device in the shoe of an individual, do we know the effect on the opposite foot if there is no similar device afforded? No we do not. What we are providing is a basic device (unless otherwise necessary) with a similar base characteristic; shape unique to that individual and material. You would do the same for a cars tires, wheels etc.
Mostly I buy tires when required and move the back to the front and the new on the back, but the car idea is a bit of a problem when compaired to the human body. Mechanics may understand more about the effect of 1 or of 4 tires being different that we using just 1 device instead of 2.
Quote:
Originally Posted by David Wedemeyer
Perhaps because FFO's are functional and improve gait and 'moon boots' impair function. Why would you increase the likelihood of altering their gait and creating iatrogenic injury by using symmetry as a guide in this case? Occam's Razor allies here no?
You are probably correct but was trying to make a point about your biceps rehab idea.
Quote:
Originally Posted by David Wedemeyer
Precisely! Cosmetic perhaps but the doctor evaluates both eyes individually as well and dispenses them as a unit, a system. Aren't the feet a system, two like organs of the same or similar function?
The big different is that the cosmetic glass does not change function of the eye. ie it does not effect vicion where the device most likely will. It will change the shoe-foot interface to now being shoe -device-foot interface which may have positive -no -negative effects long term
Quote:
Originally Posted by David Wedemeyer
Indeed!
David I am playing Beelzebubs´ Barrister here, just looking for an interesting discussion to start the year.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Robertisaacs
Good question.
I'd answer thus (to you).
Orthoses have a wide variety of effects. There is the intended theraputic effect, reducing the tissue stress in the affected tissue. But there is a whole swathe of other effects. The kinetic effects of the rest of the orthoses. The difference in "feeling". The neuromotor element. The difference in heel height. the difference in the amount of room in the shoes. We seek to control the desired element but we affect many other things unintentionally and If we are honest, we don't fully understand the effects of these changes. Robert
this next line is the most important.
Quote:
If we are honest, we don't fully understand the effects of these changes.
so how do we know the device in the good leg is not leading to pathology ? we don´t right - so why are we issuing them
Quote:
Originally Posted by Robertisaacs
Tissue stress is about reducing tissue stress in individual tissues to within tolerable levels. There is an element of distributing stress amoung structures. To paraphrase the communist manifesto, to each according to need, by each according to ability. If we use one insole only I would have concerns that we would create such a disparity between function on the two sides, we would create other problems. Not least by createing a LLD! Robert
why would you create a LLD unless you leave mm´s of material under the heel, then there is a whole other discussion of changing the COM of the body. 1-2mm of material under the heel max 5 mm with a big skive - not likely to effect much I would think.
Also if using your arguement if the good leg was 5 mm longer then no device required ?
Quote:
Originally Posted by Robertisaacs
Re the moon boot, that situation is a bit different. If you have fractures the "need" of that tissue to be protected is paramount. We WANT the other side to do all the work!
If I have one side which looks straight down the line as I would want it to, and the other patholgical, I'll do a "blank" for the good side. Minimal interferance, no posting, no mods and morphology similar to the pathological side. But I think it is right that they have something in both sides to accomodate all those unknown effects. Robert
Whats a blank device ? any device will have some effects - Ive got days of reading re leg stiffness, muscle stiffness and pipers rhythms for you. Change the stiffness at the foot interface will change the function of the body.
As to shape if you are using a lateral skive and lateral post to reduce loads on the medial meniscus you would do the same for the other, but you said you would not post, mods etc so what device do you choose then ?
Quote:
Originally Posted by Robertisaacs
To the patient I'd say "otherwise you'll walk in circles!"
Cheers
Robert
I think you mean a one legged duck in water. Who I think is called Frank.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by m weber
why would you create a LLD unless you leave mm´s of material under the heel, then there is a whole other discussion of changing the COM of the body. 1-2mm of material under the heel max 5 mm with a big skive - not likely to effect much I would think.
One day, when I was teaching how to make orhtotics in the lab, by orthotic broke. By the end of the day my back was beginning to tighten up. Although the students did get so see how to make a device from a broken one.
The thread is dancing around a very interesting question. Can tissue stress measurements, observations predict pathology. Even though a foot is asymptomatic, you could see a callus sub 2nd metatarsal or see a medially positioned STJ axis. You could look at the impression of the foot in the shoe and see if there were any areas of high pressure. Quite often in PT dysfunction the other foot has a quite medially positioned STJ axis.
So, if you have one foot that hurts and another that is perfect, then what do you do. To keep the amount of lift under both feet even I would make an arch support with no skives or intrinsic posts. It's hard to see how that could increase stress on any structure.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by efuller
One day, when I was teaching how to make orhtotics in the lab, by orthotic broke. By the end of the day my back was beginning to tighten up. Although the students did get so see how to make a device from a broken one.
From my reading of your posts Both your feet are not in the best biomechancial shape.
Maybe I´ll try 1 device tomorrow see how it goes, but again I´m far from being 1 side painfree with no history of overuse injuries.
Quote:
Originally Posted by efuller
The thread is dancing around a very interesting question. Can tissue stress measurements, observations predict pathology. Even though a foot is asymptomatic, you could see a callus sub 2nd metatarsal or see a medially positioned STJ axis. You could look at the impression of the foot in the shoe and see if there were any areas of high pressure. Quite often in PT dysfunction the other foot has a quite medially positioned STJ axis.
If you wanted to get quite fancy you could look at the cross sectional area of the PT tendon to see if any positive tendon adaption has occured. An compare this to the painful side and if the tendons have similar cross section area then treat.
Quote:
Originally Posted by efuller
So, if you have one foot that hurts and another that is perfect, then what do you do. To keep the amount of lift under both feet even I would make an arch support with no skives or intrinsic posts. It's hard to see how that could increase stress on any structure.
Eric
What if we are dealing with just 1 knee ? and the feet are symptom free ?
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by m weber
From my reading of your posts Both your feet are not in the best biomechancial shape.
In Kevin's anterior axial projection study I was one of the outliers in the direction of medial deviation of STJ axis. My dad has essentially the same foot as me and went on to get a keller procedure for OA of the first MPJ. My feet haven't got any worse since wearing orthotics. When I take my kids to the water slide park (no shoes or orthtotics), I have to consciously walk less propulsively or I'm really hurting the next day. That's all the proof I need that orthotics work, but that doesn't get very high on the quality of research scale.
Quote:
Originally Posted by m weber
What if we are dealing with just 1 knee ? and the feet are symptom free ?
I have a patient with genu varum and sinus tarsi pain. The orthotics that help his sinus tarsi pain bother his knees at some point down the road. I've taught him to strap a coin under the medial forefoot of his orthotic when he gets sinus tarsi pain and to remove it when gets knee pain. Seems to work for him. So, if you can identify the stresses that bother the knee, then you can warn the patient of what foot consequences may occur from your treatment.
I like the tissue stress explanation of medial compartment pain with genu varum. However, I'm not so happy with the explanation of how orthotics treat patelofemoral pain. There's a thread in discussion of that.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by m weber
Was having a discussion with a patient today about tissue stress theory and treatment.
After we had gone over a few of this basics, he came up with ´its a bit like a car mechanical just fixing what is broken ´
I said thats not a bad way of looking at it.
He has unilateral pain and the next question was - why do I need a device for both feet then ?
I went on to expalin about hip and back being balanced etc...
But it got me thinking a bit - if we follow tissue/physical stress theory and pain is on one side only one device should be used.
Does anyone know of a study that looks at the effects of only using one device ?
We have discussed not mirroring devices, I use very diferent device design from one side to the other more often than not.
So why not a single device ?
Thought for the weekend...............
Michael and Colleagues:
Good discussion.
When I give my lecture on the goals of foot orthosis therapy, here is what my lecture slide says:
Quote:
“The goal of foot orthosis therapy should be to reduce the pathologic loading forces on the injured structural components of the body in order to allow healing of the injured structures, to prevent new injuries from occurring, and to promote more efficient dynamics of the body during weightbearing activities.”
Kirby KA.: Foot and Lower Extremity Biomechanics II: Precision Intricast Newsletters, 1997-2002. Precision Intricast, Inc., Payson, AZ, 2002, p. 4.
Therefore, in using tissue stress theory to accomplish these goals, only one of the goals is to reduce stress to the tissue to allow more rapid healing. One must always remember that we must also strive toward preventing other new injuries as a result of our orthosis therapy and must also strive toward promoting more efficient dynamics during weightbearing activities with foot orthosis therapy for our patients.
The question then becomes, can we best accomplish all of the goals of foot orthosis therapy with prescribing only one foot orthosis for our patients? My answer is that in the vast majority of patients, we can best accomplish the goals of foot orthosis therapy by prescribing a pair of foot orthoses even though only one foot is symptomatic. Prescribing only one orthosis will create a limb length discrepancy, will create asymmetrical shoe fit, and unless the other foot functions perfectly, will prevent us from improving the function of an asymptomatic foot that may prevent pathology in the future.
I do, on occasion, prescribe only one orthosis, but these cases occur in only 1 in 500 patients. This most commonly occurs when the symptomatic foot has a short limb and shoe fit is vastly improved without any orthosis in the asymptomatic longer limb. Otherwise, the vast majority of patients receive a pair of orthoses and certainly the analogy to prescription eyeglasses is the one I use most often in explaining my reasoning for prescribing a pair of foot orthoses....not just one orthosis for the symptomatic foot.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by m weber
David I am playing Beelzebubs´ Barrister here, just looking for an interesting discussion to start the year.
Michael I realize that and am just trying to offer something to the discussion. You got me thinking, always a good thing!
Robert, Eric and Kevin thank you for your insights and useful thoughts. I enjoy this so much more than certain OTHER threads that are making me !!
__________________
"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." - Orville Wright
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by David Wedemeyer
Michael I realize that and am just trying to offer something to the discussion. You got me thinking, always a good thing!
Robert, Eric and Kevin thank you for your insights and useful thoughts. I enjoy this so much more than certain OTHER threads that are making me !!
Sorry David, just did not want a negative stuff.
You offer a lot to me in your posts always enjoy reading them.
Single device experiment has begun. As I'm biomechanically challenged I give myself a couple of hours, till a leg blows out. Anyone else care to join the fun?
Re: Tissue/physical stress theory and only using 1 orthotic device
I have used one orthotic for the following. When a foot has been severely injured (crush injury or severe fracture), and this results in a limb shortening, but the non-damaged foot is otherwise functionally normal, then a single orthotic has proven to be advantageous.
However, it is not uncommon to see the greater symptoms on the longer of the two limbs. Some of the worst orthotic complications (ie, postural issues) I have seen are when a single device was prescribed and then placed on the longer of the two limbs....resulting in a chronic disaster to the lower back and cervical spine. Some have actually underwent unsuccessful spinal disc decompression surgery only to find that adding another orthotic to the shorter side solves the issue completely.
Re: Tissue/physical stress theory and only using 1 orthotic device
Michael our interaction has always been positive, no worries. I felt that you asked the question wanting a friendly challenge and that is the spirit in which it was meant.
Quote:
Originally Posted by Dananberg
I have used one orthotic for the following. When a foot has been severely injured (crush injury or severe fracture), and this results in a limb shortening, but the non-damaged foot is otherwise functionally normal, then a single orthotic has proven to be advantageous.
However, it is not uncommon to see the greater symptoms on the longer of the two limbs. Some of the worst orthotic complications (ie, postural issues) I have seen are when a single device was prescribed and then placed on the longer of the two limbs....resulting in a chronic disaster to the lower back and cervical spine. Some have actually underwent unsuccessful spinal disc decompression surgery only to find that adding another orthotic to the shorter side solves the issue completely.
Howard
This is a very interesting comment. I recall Michael asking me some time back about a plausible connection between the foot and the TMJ, to which I had no explanation. I wonder if Howard would be kind enough to expound on this a bit since he does mention a connection from the foot to the cervical spine?
Quote:
Originally Posted by m weber
lasted about 9 hours till the back started to say no more, but I am biomechancially challenged.
n = 1 no good , did anyone else try ?
I had a nasty bout of PF last year. My orthoses were old and I had new one casted and made, which did aid my recovery. I'm scared to go one day without them so you're on your own here Michael!
Regards,
__________________
"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." - Orville Wright
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Robertisaacs
Don't wear orthotics. Sorry.
Wot?!
__________________
"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." - Orville Wright
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by m weber
lasted about 9 hours till the back started to say no more, but I am biomechancially challenged.
n = 1 no good , did anyone else try ?
Mike,
A while ago I was dicking around with my golf shoes and trying to modify my in-shoe environment to optimise for the different demands on each foot during the swing. Tried all sorts of stuff over a period of a few weeks, and one day wore just my left device for a round. Next morning = bad times for my lumbar spine. Never again.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Robertisaacs
Don't wear orthotics. Sorry.
Your the perfect patsy. Whip out a foam box, make a single device and see what goes on, maybe make a couple different ones be intersted see where it hurts or doesn't and if different from device to device.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Ian
Mike,
A while ago I was dicking around with my golf shoes and trying to modify my in-shoe environment to optimise for the different demands on each foot during the swing. Tried all sorts of stuff over a period of a few weeks, and one day wore just my left device for a round. Next morning = bad times for my lumbar spine. Never again.
L4 -L5-S1 sort of region ?
Mine was David i recon we need to look at thread again, maybe if Howard replys we can use that tostart it up again.
Re: Tissue/physical stress theory and only using 1 orthotic device
Yep - L4/L5. And a nasty side effect of pulling all my shots left, but in hindsight thats no surprise as I guess it was alike to hitting the ball from an uphill lie every shot.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Don't wear orthotics. Sorry.
Quote:
Your the perfect patsy. Whip out a foam box, make a single device and see what goes on, maybe make a couple different ones be intersted see where it hurts or doesn't and if different from device to device.
Righto. What would you like me to make? And for which foot? I have an assymetry of some kind, RF > LF mobile / pronated in static stance. No idea if there is an LLD or not. RKnee episodes of chondramalacia patella, quiescent for about a year now. R foot occasional weird episodes of acute and severe burning pain 5th met head, 10 minutes or so, every few weeks (nerve entrapment?!). LF occasional episodes of mild 1st MPJ pain (FnHl). Don't know any other biometrics because I can't assess myself. Oh, except for the "dog poo" sign on my left ankle.
Quote:
Wot?!
Never got around to it. The symptoms I have are sporadic at worst and seem to regress by themselves in the usual way of things.
Re: Tissue/physical stress theory and only using 1 orthotic device
I wear an orthosis, singular, under my right foot to relieve my pain which radiates from my lower back, into my buttock, along the course of the sciatic nerve and into my knee and shin. Took me years of experimentation with pairs of devices to suss it out... One day I couldn't find the left to a pair of orthosis and as I was running late, I just put the right one in= pain gone that day. Next question: what kind of device do you wear? I wear a low density "old skool" AOL, but only when my back/ arse/ leg starts playing up. I slip it in for a few days and job done. It's now nearing it's 20th birthday. Trust me, I've tried lots of OTC devices and custom devices, but that's the baby that does it for me.
Talking of psychological influences, during the course of writing this, "my pain" has started to come on... Jeeezzzzz.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
but only when my back/ arse/ leg starts playing up. I slip it in for a few days and job done.
First time I read that sentance I got ENTIRLY the wrong idea!!
Thats an interesting example. It would appear from that that the contralateral insole actually prevented the one under the affected side from working. I wonder why! LLD?
I wonder what would happen if you used the insole for the affected side and a heel raise on the other?
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Robertisaacs
First time I read that sentance I got ENTIRLY the wrong idea!!
Thats an interesting example. It would appear from that that the contralateral insole actually prevented the one under the affected side from working. I wonder why! LLD?
I wonder what would happen if you used the insole for the affected side and a heel raise on the other?
I thought about that idea as well.
As for you device if you the you tube cast on your left side, 3mm med skive with rev. Morton ext.materials of your choice.
Re: Tissue/physical stress theory and only using 1 orthotic device
Oh that. Righto. Cast with maximally plantarflexed 1st met. I'll get one of my minions to do it for me. 3mm Medial heels skive and reverse mortons. I'll get right on it.
Re: Tissue/physical stress theory and only using 1 orthotic device
Quote:
Originally Posted by Robertisaacs
Oh that. Righto. Cast with maximally plantarflexed 1st met. I'll get one of my minions to do it for me. 3mm Medial heels skive and reverse mortons. I'll get right on it.
Dear above mentions minions, a few questions.
Have you gone on strike for being called minions ?
Has boss man forgotten to ask for a cast or get device made ?
Is boss man walking around mumbling about kinesiology testing and you don´t wish to approach with finished device due to the 1 hour rant which may follow ?
Tissue/physical stress theory and only using 1 orthotic device
!!
Sorry.
Wot?!
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