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Post by robertisaacs on Nov 7, 2007 18:38:41 GMT
Ah yes, the much maligned "simple" insole. "to deflect pressure" as i see on many a referral. "Its not functional" as i hear a colleague whimper before i beat them about the head and neck with a pelvic level* for knackering a patients knees with an insole without doing the patient the courtesy of assessing them first. I forward the following statements for consideration. Definition first simple insole - An bespoke insole manufactured by adhering components to a flat base then applying a cover. Usually templated by marking the patients feet in some way, placing a template in their shoes and having them put their foot in the shoe. [glow=red,2,300]"A simple insole ALWAYS has a functional effect" "A simple insole can have as profound a functional effect as a casted insole" "A simple insole, by nature of the freedom it affords a clinican, can be more complex in design and effect than a custom insole" "A simple insole is as deserving of the title "functional orthotic" as a casted insole"[/glow] (i know you're out there martin  ) Discuss Regards Robert * Disclaimer. I have never, accidentally or on purpose assaulted a colleague with a pelvic level.** **they break too easily (both pelvic levels and colleagues) |
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Post by dtt on Nov 8, 2007 10:39:45 GMT
Hi Robert OK here goes , To a degree yes as any support would but I think where any serious extrinsic posting is required or where non linear sporting activity is involved the stability and durability is brought into question. I suppose it could be argued that most trainers now contain a type of "simple insole" and I ( and I'm sure many of us) advise a lot of our patients to wear them when their feet are working hardest ,and that alone can resolve a lot of issues. So in that context alone "they must work"?? I agree there if for example a pt requires a met pad in the long term to use a simple insole design for mounting the pad would have a very profound functional effect. I understand the logic of that as you are maximising available space and that in itself allows more variation in application, but, would not the casted FFO be the same in bulk in the end ?? Could be if modified by "the right hands" and for use in "limited" situations. Just my thoughts  Cheers Derek |
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Post by Admin on Nov 8, 2007 15:28:15 GMT
I forward the following statements for consideration. Definition first simple insole - An bespoke insole manufactured by adhering components to a flat base then applying a cover. Usually templated by marking the patients feet in some way, placing a template in their shoes and having them put their foot in the shoe. [glow=red,2,300]"A simple insole ALWAYS has a functional effect" "A simple insole can have as profound a functional effect as a casted insole" "A simple insole, by nature of the freedom it affords a clinican, can be more complex in design and effect than a custom insole" "A simple insole is as deserving of the title "functional orthotic" as a casted insole"[/glow] (i know you're out there martin ) Discuss Hi Robert, No question - a simple insole almost always has a functional effect, and this can be as profound as a casted device. A simple insole can certainly be more complex in design than a casted insole. Shoe design and height of heel have functional effects too, as does the supporting surface if it is undulating or not uniform in its stiffness. I guess you could say a drawing pin pointy-side up in the shoe would have a functional effect too, but not necessarily to the benefit of the patient ;D I prefer casted insoles because: A good shell is a comfortable and durable medium for carrying correction and/or deflection. A rigid shell can provide the same support and deflection as a simple insole, but at a fraction of the volume of flexible material needed to hold the same shape for long. Regards, |
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Post by robertisaacs on Nov 8, 2007 19:50:07 GMT
Hey Derek. Thanks for replying.
I would say that its as easy to whack extrinsic rearfoot and easier to apply forefoot posting on a simple as a cast. Cobras and tadpoles are quite useful in that respect. However i accept that you cannot exert force over as large a surface area of the midfoot area on a simple and that might limit the amount of force you can exert through the midfoot.
Personally i almost never use casted insoles for sports. That, however, is yet another thread. I know i'm in a minority there.
Agreed
Actually i was thinking more of the freedom that simples afford in terms of mods than bulk. With Casts you are limited to what shape you can hold the foot when casting or what you can do to the positive cast. With a simple you can do anything your little heart desires.
Bulk wise i find neither is inherantly more or less. Depends what you put on it.
Agreed. Some patients need one, some the other. The thing i always find odd is how simples are often regarded as the poor cousin.
Kind regards
Robert
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Post by robertisaacs on Nov 8, 2007 20:03:05 GMT
Hey David
All good points. a few things i would ask Re your last.
How so? If you make your valgus pad from a material which resists compression (ie eva) It will have the same volume. Less actually because a regen and topcover base is thinner than a 2 mm shell and you don't have to have any bulk other than where you want it. I guess it depends if you are a beleiver in the good Prof Kirby's work.
However i often don't want to use a rigid valgus pad. I often WANT pronation to take place, just with some resistance and at an appropriate time and speed. That also is another thread (gosh what a lot to talk about!)
I've never fully understood the perception that a simple or indeed a shank dependant solid casted insole is inherantly more bulky than a shell. If the contours presented to the foot are the same then what does it matter if the foot sits on a shell over a void or a solid bed of material? Compressability is modifiable in either case as is the spatial location of the top surface of the insole.
Kind regards
Robert
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Post by dtt on Nov 8, 2007 20:43:40 GMT
Hi Robert No worries always happy to help Yep I think that is the fundamental problem with the simple. The midfoot (mtj unlocking ) can only be adequately controlled by a more substantive device so that in itself limits its effectiveness in the treatment of many conditions ( just my thoughts on that one as well) But surly the more mods you add the more the bulk increases?? So does not the casted ( Davids point) win overall ?? I take your point simples do have their place, BUT, in the context I was referring to in the other thread the " the drawing round the foot bit" resulted in many cases to inappropriate devices that were ineffective for the child, did not resolve the issues, and were not followed up to check their effectiveness. Which ( being the cynic that I am) would consider the "cheap option" is being used wherever possible as a directive within the system.  Hence the Pi**ed off parents and child. I'm sure you will correct me, (BTW it is not meant to be a criticism in ANY way to ANY pod working in the NHS. I bow in many cases to your greater knowledge) should you feel the need , but it's just how they present to me. I wish you worked in my area I would drive you bloody mad with referrals ;D ( all of which would have been properly assessed beforehand  ) and would give the child /parent free at end user status. Yep I still believe in the NHS and can never ever hope to match the resources within ( you included) but again for the patient, IT AIN'T HAPPENING  Not moving off the point, just tellin it like it is Cheers Fella Derek |
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Post by dtt on Nov 8, 2007 21:03:36 GMT
Hi Again Robert You posted before my reply to the last ( sorry). Interesting thought ,but does not the GRF as opposed to the body mass come into the equasion ?? Flexibility to a greater or lesser degree ?? You referred to fast / slow recovery materials earlier all of which are to do with flexibility within a device. Do you get the same in a "solid bed" ?? Which again goes back to "the more you add the more bulk you increase to the top surface / overall ?? Compressibility = flexibility but I think that is more effective and controllable with "the shell". My thoughts Cheers Derek |
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Post by robertisaacs on Nov 9, 2007 20:21:23 GMT
I'm enjoying this! ;D Depends on the mods. I think overall it depends on what the patient needs. If the patient needs a countertorsional wedge (for adducted gait for eg) its a lot less bulky on a simple. Can't correct you, as much as i'd love to. Because this is obviously your experiance of simples local to you. I saw one today from our surg appliances dept which was absolutly revolting. Beurko cork (who the hell makes a simple with beurko cork?!) valgus pad which was the wrong size, the wrong shape, and in the wrong place! NO other mods. As for being the cheap option... i'd love to correct you there as well. But i am afraid i have long since ceased to be amazed at some of the things that go on in the NHS. If they are being used as a "directive from above" that might explain why they are being used inappropriatly. Thats what happens when managers get involved in clinical decisions. It sounds to me that the problem in your locale is a poor diagnostics coupled with shoddy production and inappropriate prescriptions. Not following a patient up to ensure your devices are in the right place and working effectivly is poor practice IMO. However i do not feel any of these faults are inherent to the nature of simple insoles. There's nothing wrong with using a screw, unless you pound it in with a mallet. I don't follow there. Sorry. Surely GRF and downward force occasioned by body mass at a point are equal and opposite. Don't realise what your point is on flexibility either. Could i have that again in small words for the hard of thinking? Regards Robert |
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Post by dtt on Nov 9, 2007 23:34:45 GMT
Hi Robert I hope so we all usually do on this site and that's how it should be We have broad agreement on the body of the foregoing so I will try to clarify my thinking for you. Agreed, but is the point of the orthotic to deflect and rationalise both to restore an equilibrium to allow proper foot / joint function?? OK , I view the foot as 3 levers rearfoot ,midfoot and 1st met mtj. Now for the foot to function correctly we have to have a degree of flexibility in the joints and in the foot as a whole or everyone would be walking as if they had divers boots on . When we make an orthoses for a patient do we not post to add rigidity to one part to allow a degree of flexibility in another part of the foot to allow proper function?? Example is with an ankle equinus, is not a heel raise to plantar flex the foot to allow more Dorsi Flexion in the ankle during gait? When we medially post the calcaneum are we not giving a degree of rigidity to that part but in doing so restoring the correct motion (flexibility) of the STJ ?? The point I was making was I do not believe a simple on a flat bed even with compressible materials used for postings/ wedges etc an ever compete with a semi rigid shell. ;D ;D Did you know BOW LOCKS were in Essex ?? I wish I was as hard of thinking as yourself !!;D ;D ;D Cheers Fella Derek |
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Post by ianl on Nov 10, 2007 6:25:55 GMT
Hi
Interesting point on rigidity.
Not convinced that we achieve making the foot more"rigid" even if we manage to help the locking mechanism at early heel lift. I suspect that the foot does not become more rigid on a device so much as responds differently against the altered resistance a device makes as a supporting surface.
Equally suspect that the idea of the MTJ locking mechanism (giving a rigid lever) having to kick in at each step is very much surface related and that barefoot over alternating terrain the foot would not require the input of the locking mechanism quite as much as we do on regular surface. Agreed, this latter point is based mainly on my own limited experience and I acknowledge that the regular surface is what we have these days.
So rigidity of devices, even if it is of various densities in any one device, may be important but not because a device helps a foot become more rigid rather, possibly, because it alters resistance to the foot. Quite what combination of proprioceptive/exioceptive feed back is involved I do not know and I'm sure we have yet to take into account more superior body feedback as well.
One thing about mods to simples is that you can alter density and resistance quite easily. Interestingly I knew a number of chiropractors, for a while, who favoured "foot cradle" devices. Nothing more than a complicated simple (an oximoron?) really with varied densities of material for different parts of the foot. Quite impractical for many ladies shoes but got results for some people.
Ian
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Post by dtt on Nov 10, 2007 14:22:36 GMT
Hi Ian I think you have misinterpreted what I said I will try to expand. I was quoting that as an example of how we a "flexibility to a joint by adding rigidity (posting) to the orthotic You add a rigid heel raise to give flexibility to the ankle You ad a rigid medial post to restore the flexibilty ( ROM) if the stj Of course as you say the foot must at various point become rigid but I was referring to the orthotic and its effect on the foot. I'm not sure what you mean by "foot cradle" devices?? Obviously footwear issues come into the equation when Rxing any orthotic but with the availability of many different types ( including those based on the simple which incidentally I also use) from labs these days we are almost "spoilt for choice" Cheers Derek |
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Post by robertisaacs on Nov 10, 2007 14:41:06 GMT
Interesting idea. When you say levers do you mean pivots or the lever itself? What planes are we talking about. I like the way you are considering the foot, i'd like to understand you better there.
So your point (if i have understood you correctly) is that a rigid modification in one segment of the foot relates to increased movement in another.
I think i can see what you mean. I suppose it comes back to what we try to do with our device.
One question i always have fun with with students (evil sod that i am) is how much pronation takes place in a gait with medial heel strike and loading and no real recovery into supination. They usually say lots or that the problem is overpronation. Which of course is not the case. The foot is pronatED not pronatING. The more effective (you could say rigid) the modification to create rearfoot inversion, the more eversion becomes available later in gait and paradoxiacally, the more pronation we create.
Certainly in the above case i can see how a casted insole would be correct and a simple, inadequate. However what of the following.
Lets take a patient who has a pronatory pathology (lets say anterior knee pain). He presents with normal biometrics joint ranges etc but tibialis muscles which are not equal to the task. He pronates to a normal degree but too quickly and not in a controlled way so that when he hits his maximally pronated position (limited by a combination of tibialis maximum stretch and deltoid tension) he comes to a sudden stop and stays their too long so he does not resupinate after mid stance.
With a rigid casted device we have several options.
We could cast a device which would keep him near STN, but that would rob him of effective pronation as much as his present state
.
We could cast him so that he can still pronate to a degree, but not so far, in the hope that the shorter drop would mean less momentum and the more lateral STA would give his tibialis group (hopefully) enough mechanical advantage to work effectivly, but this would limit the pronation available.
Or we could cast him with a FF wedge in order to increase supination moments from resistance to inversion in the MTJ, (but i'd worry about the long term effects on his MTJ.
I'm sure you could think of a few more good prescriptions, possibly something in the semi rigid line. But personally i find it much harder to "calibrate" flexibility than compressibility.
Personally i would use a simple with a laminate Valgus pad, say poron over diabet. I would aim to calibrate it so that the pad contacted his MTA area early in pronation and was compressable to the extent of his pronation (so i am not actually limiting how far he moves.) The rationale would be that the increased and increasing resistance to pronation from the Pad would supply enough supination moments to bring the requirement on the tibialis group within its capabilities. The elastic recoil nature of the pad would also provide a resupination force as the foot unloads to encourage the foot back after mid stance.
For me its different strokes for different folks
Regards
Robert
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Post by dtt on Nov 12, 2007 15:51:25 GMT
Hi Robert From heel to midfoot to 1st ray . Three separate levers ( all with their own planal variance) but in essence each one leads to the next to give the main rigid lever we need in propulsion. Yes and or restoring the ROM required to allow the next part of the lever mechanism to function correctly as above That's exactly right bear in mind we were discussing "orthotics" here, and I am simply describing my thoughts on how I view the simple mechanics of the foot and what I want to achieve from the orthotic. I then add the finer points. I must say at this point that the use of a pressure plate gives a different perspective as you can actually see early heel lift, abnormal pressures and joint function so that in itself help to build a picture of what you are trying to achieve with the orthotic I tend to agree there but I with certain individuals, to find a wearability factor with a semi rigid device over a solid one ,but as you say it depends what you want from the orthotic as to which type to use for each individual. Cheers Derek |
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) and would give the child /parent free at end user status. 