Home Forums Marketplace Table of Contents Events Member List Site Map Register Mark Forums Read



Welcome to the Podiatry Arena forums, for communication between foot health professionals about podiatry and related topics.

You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members (PM), upload content, view attachments, receive a weekly email update of new discussions, earn CPD points and access many other special features. Registered users do not get displayed the advertisments in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!

If you have any problems with the registration process or your account login, please contact contact us.


Tags:

Testing functional performance of custom therapeutic footwear

Reply
Submit Thread >  Submit to Digg Submit to Reddit Submit to Furl Submit to Del.icio.us Submit to Google Submit to Yahoo! This Submit to Technorati Submit to StumbleUpon Submit to Spurl Submit to Netscape  < Submit Thread
 
Thread Tools Display Modes
  #1  
Old 22nd November 2011, 04:35 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Testing functional performance of custom therapeutic footwear

Podiatry Arena members do not see these ads
I’d be grateful for advice regarding the best way to evaluate the performance of custom therapeutic footwear regarding looking especially at efficiency of the propulsive phase of gait.

I am particularly wanting to see if the shoe (as I suspect) is influencing vertical loading of the MP joints and therefore facilitating efficient sagittal plane function into propulsion. One way might be to look at Hallux loading / timing in relation to 1st MP joint loading with a pressure system but I’m interested in other protocols to evaluate this.

The overall idea is essentially to use custom footwear design to assist with post surgical complications where the propulsive phase of gait especially has been affected detrimentally by forefoot surgery.

Many of these patients do quite well with shoes such as MBTs / running shoes where the toe rocker effect and thicker midsole is helpful and I have found that this can often be improved upon further with certain custom adjustments to the insole and want to look at ways to actually quantify this.

Thanks

Paul
Reply With Quote
Sponsored Links
  #2  
Old 22nd November 2011, 09:24 AM
efuller efuller is offline
Podiatry Arena Veteran
 
About:
Join Date: Jun 2005
Posts: 2,206
Join Date: Jun 2005
Marketplace reputation 0% (0)
Thanks: 21
Thanked 389 Times in 325 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post
I’d be grateful for advice regarding the best way to evaluate the performance of custom therapeutic footwear regarding looking especially at efficiency of the propulsive phase of gait.

I am particularly wanting to see if the shoe (as I suspect) is influencing vertical loading of the MP joints and therefore facilitating efficient sagittal plane function into propulsion. One way might be to look at Hallux loading / timing in relation to 1st MP joint loading with a pressure system but I’m interested in other protocols to evaluate this.

The overall idea is essentially to use custom footwear design to assist with post surgical complications where the propulsive phase of gait especially has been affected detrimentally by forefoot surgery.

Many of these patients do quite well with shoes such as MBTs / running shoes where the toe rocker effect and thicker midsole is helpful and I have found that this can often be improved upon further with certain custom adjustments to the insole and want to look at ways to actually quantify this.

Thanks

Paul
Paul,

Well the first step is to define performance. What is improved performance? Is the measurement that you take a valid indicator of performance? Is your measurement accurate.

Do you really want to look at the efficiency of the propulsive phase of gait? What would a more efficient propulsive phase look like. Why does loading of the hallux and first met head have a relation to efficiency of the propulsive phase of gait?

It sounds like you have an in shoe pressure measurement system. If you do looking at pressures under the first ray would be fairly easy to do and possibly yield interesting and valuable results. However, you have a long way to go to correlate first ray pressures with gait efficiency.

Is an increase in first ray pressure a good thing? Is there an optimal range of first ray pressure with there being a too high and a too low?

When studying gait you have to remember there is a brain connected to the foot. The brain may change muscle activation in response to changes in experimental variables. There have been studies that show that rocker bottom shoes reduce pressures on the forefoot. However, the patient with reduced pain may choose to walk faster producing what may appear to be a more efficient gait.

Eric
Reply With Quote
  #3  
Old 22nd November 2011, 02:26 PM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

Eric

Thanks very much for the reply.

What I mean by improved performance is better overall perceived comfort for the patient when compared to a control shoe without properties that assist vertical loading of the metatarsal. In addition to this I would like to see some consistent measurable effect that might lead me to conclude that this correlates accurately with the better comfort scores.

I agree – I’m not sure whether increased 1st ray pressure is a good thing and that a pain response might well alter the gait.

Most complications from forefoot surgery seem to involve pain going into or during propulsion. This from my observations seems to be related to for example stiffness in the MP joints, metatarsal length variations, alterations in gait due to pain, altered mechanical function from the surgical procedure causing different loading patterns etc. I’m not going to include neuropathic pain patients in the study. I might also out of curiosity try and include some control group pain free patients who have not had surgery and see if they observe any better comfort from one shoe versus another and see if this can be measured.

This query has arisen because I have found through experience that when I see these problems the patient’s pain seems to be helped by suggesting the patient use a combination of a rocker sole effect combined with an insole - but the thicker the insole, the better the pain relief.

I am presuming that the cushioning material somehow allows the metatarsals to find their own level thus evening out high pressure areas. The softer material also might be increasing sagittal plane motion of the vertically moving ray (assisting propulsion) and the rocker sole effect speeds propulsion reducing force over time – already known to some degree.

I don’t think the effect is as good though with just a rocker sole so I think the thick cushion under the met heads is a very important addition.

I want to devise a study that will show that there is some merit for patients with post op forefoot surgery propulsion pain in suggesting a rocker sole combined with a thick forefoot cushion and I want to try and determine if there is a measurable effect that might suggest what the real reason is for this. I suspect is a combination of pressure equalisation, assisted vertical loading of the mets and less force over time when compared to a control shoe with a thin sole and minimal cushioning under the metatarsals.

It might be that one of these factors is more relevant than another and it would be good to know that. Is there a consensus on:

• What is the best way / equipment to evaluate vertical loading of the metatarsal heads on a soft material versus a harder material

• What is the best way / equipment to evaluate force versus time as the foot moves from metatarsal loading into propulsion to swing phase

• What is the best way / equipment to measure pressure redistribution under the metatarsals from initial pressure to peak loading

Perhaps this is totally the wrong approach and I should be looking at other things? Any suggestions much appreciated

For the test I was planning on using

A rocker sole shoe with no forefoot cushion
A thin soled shoe with no rocker
A non rocker sole shoe with a cushion
A rocker shoe and cushion

My gut feeling is that metatarsal stiffness and metatarsal length variations are highly significant as I see these most with post op pain.

My pain free patients seem to be the ones with good post op MP joint motion and no major metatarsal length variations. The one fly in the ointment seems to be post op joint replacement where joint motion and met length is ok but the plantar fascia function seems compromised and the feet seem to either pronate or supinate at the forefoot (usually supinate as a result of Tib Ant overactivity which might be a deliberate compensation).

Is there by any chance an agreed way of consistently evaluating plantar fascia function in this scenario with gait analysis equipment.

Thanks

Paul
Thread Starter
Reply With Quote
The Following User Says Thank You to Paul TG For This Useful Post:
javi yagüe (24th November 2011)
  #4  
Old 22nd November 2011, 02:52 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

When we do rocker soles for our high risk DB clients we use the Fscan in-shoe system.

This gives me peak pressures, but it also gives me the thing that most seem to miss and that is time of travel over the effected area, trajectory.

In the pics below you cant see but the white trajectory line is broken into segments, each segment is worth (l would have to look it up) a unit of time, lets say 1 sec, the longer the segment the quicker the travel time over that area.

First picture shows a very poor trajectory line as the client rocked back just prior to toe off.
Attached Images
File Type: jpg poor result.jpg (53.5 KB, 96 views)
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
  #5  
Old 22nd November 2011, 02:57 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

With an adjustment to the fulcrum position of the rocker sole you can see how the time and direction of the trajectory line has improved, no other adjustments have been made at this time.

If you have interest in this type of thing you should come to http://www.ivo2012.org.au
Attached Images
File Type: jpg improvement.jpg (54.4 KB, 94 views)
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
  #6  
Old 23rd November 2011, 04:04 PM
hontas's Avatar
hontas hontas is offline
Member
 
About:
Join Date: Aug 2009
Posts: 9
Join Date: Aug 2009
Marketplace reputation 0% (0)
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Testing functional performance of custom therapeutic footwear

What do you mean by 'vertical loading'?

If you have a plantar pressure measurement device this will not measure 'vertical' force/loading anyway.

It will measure the normal force acting over a defined area which is not the same as the vertical component of the GRF vector.

Pressure and force = different.
Reply With Quote
  #7  
Old 24th November 2011, 08:40 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

HONtas you wrote What do you mean by 'vertical loading'?

If you have a plantar pressure measurement device this will not measure 'vertical' force/loading anyway.

It will measure the normal force acting over a defined area which is not the same as the vertical component of the GRF vector.

Pressure and force = different

I realise pressure and force are different. What I mean by vertical loading is the effect when the metatarsal moves vertically and consequantly sinks into the cushion material which helps the sagittal plane motion due to the softer surface. Presumably this will not happen to the same degree on a harder surface wherre the MP extension will be predominantly dependant upon the joint motion. The cushion material by allowing the met to move more vertical might offset any restriction in pur MP joint extension.

How could i measure this effect?

Thanaks

Paul
Thread Starter
Reply With Quote
  #8  
Old 24th November 2011, 02:53 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

IMO soft materials reduce impact but increase time.

e.g If we place a S.A.C.H on a shoe it reduces impact on the heel and slows the forefoot lowering, meaning the client spends more time on the heel.

Same for padding anywhere else on the foot, you cant move forward until the soft material bottoms out and that takes time.
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
  #9  
Old 24th November 2011, 07:07 PM
hontas's Avatar
hontas hontas is offline
Member
 
About:
Join Date: Aug 2009
Posts: 9
Join Date: Aug 2009
Marketplace reputation 0% (0)
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Well there would be two different things you seem to want to measure. Correct me if I am wrong:

1. the sagittal plane displacement of the metatarsal head (1st met?). I don't think vertical is the right word - movement will not be in one degree of freedom here either.

2. the amount of pressure at the interface between the plantar aspect of the metatarsal head on the supporting surface (under different material conditions)

Number 1 - complex and would require a kinematic model derived from motion analysis data with ideally each metatarsal modelled as a single segment/entity. You would need a decent system to track markers of that number and size. Doing this in-shoe is a whole different story.

Number 2 - plantar pressure measurement device will do this (in-shoe), however the resultant pressure measurement will be highly dependant and influenced by the properties (i.e. density) of the material beneath the metatarsal head. Therefore any differences in pressure between conditions may be a function of the materal itself rather than any other factor modified.

Hope this helps.
Reply With Quote
  #10  
Old 24th November 2011, 11:07 PM
efuller efuller is offline
Podiatry Arena Veteran
 
About:
Join Date: Jun 2005
Posts: 2,206
Join Date: Jun 2005
Marketplace reputation 0% (0)
Thanks: 21
Thanked 389 Times in 325 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post
I realise pressure and force are different. What I mean by vertical loading is the effect when the metatarsal moves vertically and consequantly sinks into the cushion material which helps the sagittal plane motion due to the softer surface. Presumably this will not happen to the same degree on a harder surface wherre the MP extension will be predominantly dependant upon the joint motion. The cushion material by allowing the met to move more vertical might offset any restriction in pur MP joint extension.

How could i measure this effect?

l
Paul,

I don't understand what effect you want to measure. The joint can dorsiflex regardless of what density of material it's on. Are you talking about measuring MPJ stiffness?

Eric
Reply With Quote
  #11  
Old 25th November 2011, 02:47 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

Thanks for the feedback.

David – What is a S.A.C.H?

Eric – the joint might can dorsiflex whatever the material but do you think that a softer material will assist this process by allowing the metatarsal to achieve a more plantarflexed position relative to the toe than would occur if the met head was on a harder material?

Hontas - Number 1 - complex and would require a kinematic model derived from motion analysis data with ideally each metatarsal modelled as a single segment/entity. You would need a decent system to track markers of that number and size. Doing this in-shoe is a whole different story.
What would be required to do this, theoretically I can access whatever equipment I would like to use for the study – I just want to do the right study in the first place

I wonder though from the feedback if I am approaching this the wrong way – perhaps I could just ask your opinion on what you think is the reason for this positive effect I have observed and how this might be effectively evaluated objectively.

It seems very clear that these patients feel much more comfortable using a shoe with a replacement cushion insole (which is also thicker and softer than the surrounding material under the met heads) in a shoe with a thick midsole (running shoe).

The patients subjectively report that they feel like they are pivoting over their foot better than in a thin soled flexible control shoe or when using the running shoe without the cushion sole.

Trying to break it down into what could be happening - I had assumed that the positive effect might be related to these possibilities but would like to be able to objectively prove it. Perhaps though I am overlooking something much more important?

1. The softer material under the metatarsals seems to have some sort of positive effect – what could it be?

2. Is the softer material somehow assisting the sagittal plane motion of the metatarsals and if so how? Certainly these patients will often have MP stiffness in varying degrees but not all (although they might have it functionally but I cannot detect this clinically). Does the softer material by allowing the metatarsal to effectively drop further down that in a rigid sole somehow compensate for any MP stiffness?

3. The natural rocker effect from a shoe with a running shoe type midsole presumably helps toe extension and more so if you have any MP stiffness. I was wondering whether this would induce less force over time with a faster propulsion but if the softer material slows motion (increasing the time to sink into the material) what is really happening here?

Generally from what I have read softer materials in greater surface contact with the foot overall do reduce pressure but do you think this could be the most positive effect in this instance? I say this because if I just use a running type shoe with a thin insole the subjective comfort scores are much poorer so the rocker angle effect might be relevant.

So what is the opinion on what is really happening here? Is it just simple pressure reduction via bigger surface area contact or is there an effect where the sagittal plane motion into propulsion is being improved and if so how and how could this be objectively measured (what equipment would I need) or is there some other effect at work that I am missing?

I appreciate that when studying this, that the overall biomechanical function of the patient is also relevant and might well affect the results. However, what I find interesting here is that almost universally this effect gives higher comfort scores no matter what the problem post surgically.

By analysing this in more detail I hope it becomes clearer just what is really happening and that this info can then be used to improve treatment.

Thanks very much for your input.

Paul
Thread Starter
Reply With Quote
  #12  
Old 25th November 2011, 03:01 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

S.A.C.H
Solid Ankle Cushioned Heel.
A heel rocker made, a PU sponge material is then used to fill the area where the rocker was cut into the sole and covered at sole level.

l will put a pic up end of next week as l am doing one currently for a DVA client.

l will suggest that the soft material at the MPJ may just be increasing the Windlas position, as the mid foot has support and the MPJ sink lower into the soft compound, which can unlock/reduce the functional Hallux stiffness IMO.

Take a client with functional Hallux stiffness, do a jack's test with a foot unsupported, now elevate and support their arch and try the jack test again, does the Hallux move with less resistance?
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
  #13  
Old 25th November 2011, 06:43 PM
efuller efuller is offline
Podiatry Arena Veteran
 
About:
Join Date: Jun 2005
Posts: 2,206
Join Date: Jun 2005
Marketplace reputation 0% (0)
Thanks: 21
Thanked 389 Times in 325 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post
Eric – the joint might can dorsiflex whatever the material but do you think that a softer material will assist this process by allowing the metatarsal to achieve a more plantarflexed position relative to the toe than would occur if the met head was on a harder material?


I wonder though from the feedback if I am approaching this the wrong way – perhaps I could just ask your opinion on what you think is the reason for this positive effect I have observed and how this might be effectively evaluated objectively.
My theory: the soft material is more comfortable so the patient feels more comfortable when they place their entire body weight on their metatarsal heads so they choose to do this for a longer period of time.

Paul, are you aware of the concept of a functional hallux limitus?

I don't feel that equally soft material under all of the metatarsals will create a mechanical effect that allows the MPJ's to dorsiflex more. I think the changes that you described can be attributed to the central nervous system and not to the mechanics of the material. You can alter the stiffness of individual MPJ's by decreasing tension in the slip of plantar fascia for that ray. One way to do this is to put softer material under that ray and leave firmer material under the other rays.

If the MPJ remains rigid after heel lift, this may become uncomfortable and the patient may choose to not plantar flex their ankle so much. If there was a uniformly softer material under the entire forefoot, the ankle angle at which an uncomfortable pressue develops may develop may be more plantar flexed.

An interesting study would be to measure ankle plantar flexion angle in gait with and without soft insoles. That would prove that the effect you describe is actually occurring. Then you could measure plantar pressures and correlate them with ankle plantar flexion angle with the different materials.


Eric
Reply With Quote
  #14  
Old 26th November 2011, 10:49 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

David. Thanks, if there is an improved windlass effect could this be measured as per Eric’s comments?


Eric

Thanks. I’m aware of the concept of functional Hallux limitus and the influence of the pl fascia tie bar system as described by David Stainsby in his paper in 1997. I am also familiar with Dr Howard Dananberg’s papers regarding this concept.

In my observations with these patients it does not seem to matter about varying the density under the met heads. In fact we have found that lowering the 1st ray tends to be not well tolerated and seems to pull the foot too far medial even if there is not an associated Tib Post insufficiency or other effect to keep the hindfoot in valgus. We have previously tried patients with the Dananberg insole product with and without the plug and it was very poorly tolerated, and nowhere near as subjectively comfortable as the thick forefoot cushion and patients also did not report the better ease in stepping over their foot with the Dananberg product.

Perhaps the thick cushion is automatically adjusting relative met head heights as they sink into the material different amounts based on relative loading – presumably this could be analysed with pressure studies

Your idea about measuring ankle plantarflexion sounds a good approach. If ankle plantarflexion increases more with the softer forefoot pad then sagittal plane motion at the MP joints has been improved. What equipment would be best to look at this and what would I want to look at on the pressure studies specifically?

Many thanks

Paul
Thread Starter
Reply With Quote
  #15  
Old 27th November 2011, 01:54 AM
efuller efuller is offline
Podiatry Arena Veteran
 
About:
Join Date: Jun 2005
Posts: 2,206
Join Date: Jun 2005
Marketplace reputation 0% (0)
Thanks: 21
Thanked 389 Times in 325 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post

In my observations with these patients it does not seem to matter about varying the density under the met heads. In fact we have found that lowering the 1st ray tends to be not well tolerated and seems to pull the foot too far medial even if there is not an associated Tib Post insufficiency or other effect to keep the hindfoot in valgus. We have previously tried patients with the Dananberg insole product with and without the plug and it was very poorly tolerated, and nowhere near as subjectively comfortable as the thick forefoot cushion and patients also did not report the better ease in stepping over their foot with the Dananberg product.
This is not my experience at all. On my own orthotics a reverse Morton's extension add significantly to comfort. What do you mean by pull the foot too far medial.

Quote:
Originally Posted by Paul TG View Post
Perhaps the thick cushion is automatically adjusting relative met head heights as they sink into the material different amounts based on relative loading – presumably this could be analysed with pressure studies

Your idea about measuring ankle plantarflexion sounds a good approach. If ankle plantarflexion increases more with the softer forefoot pad then sagittal plane motion at the MP joints has been improved. What equipment would be best to look at this and what would I want to look at on the pressure studies specifically?

Many thanks

Paul
3-d motion analysis. If you don't have that you could do a sagittal plane video and measure angle of foot to ground or of angle of foot to leg.

I don't think you can make the conclusion that MPJ motion has been improved when you see more ankle joint plantar flexion. To make that conclusion you would have to measure MPJ motion.

In shoe pressure measurement. You would want to look at 1st toe force and 1st met head force, the ratio between those forces and the force of the first met added to the force of the first toe. You'd also want to look at time of peak force. The time of peak force should be compared to time of peak plantar flexion angle seen on the video/ motion analysis.

Eric
Reply With Quote
  #16  
Old 27th November 2011, 09:47 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

ERIC WROTE - This is not my experience at all. On my own orthotics a reverse Morton's extension add significantly to comfort. What do you mean by pull the foot too far medial.

PAUL WROTE- Is a reverse morton's extesnion the same thing as dropping the 1st ray? Also how much do you drop the 1st ray. Are you trying to improve fascia function with this or specifically affect the relative MP loading for some clinical reason?

What I mean by pulling the foot too medial is that dropping the 1st ray as per the Dananberg product or creating a specific depression for the 1st met head seems to be perceived by the patient, for want of a better phrase, as over pronating the forefoot.

I would not mind this but it seem to especally irritate the medial knee and patello femoral joint. Some patients just get tib post insufficiency like symptoms. With the thick cushion some people are aware of a more medial push off but it does not seem to cause then any additional aches and pains. My observations have been that a perceived central propulsion seems most well tolerated from a comfort perspective and too far lateral not tolerated as much as too far medial.

ERIC WROTE - 3-d motion analysis. If you don't have that you could do a sagittal plane video and measure angle of foot to ground or of angle of foot to leg.

I don't think you can make the conclusion that MPJ motion has been improved when you see more ankle joint plantar flexion. To make that conclusion you would have to measure MPJ motion.

PAUL REPLIES -how can I measure MP motion? can this be done with a pressure system

thanks

Paul

ps how do I put your quote in a box above my reply as you have been doing? I can see the tick box saying include quote but it does not seem to respond.
Thread Starter
Reply With Quote
  #17  
Old 27th November 2011, 02:55 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post
David. Thanks, if there is an improved windlass effect could this be measured as per Eric’s comments?

Many thanks

Paul
The in shoe pressure system would show a difference of peak pressures at the distal Hallux if it improved, you need a comparison, a product to measure all changes from, shoe "Zero".
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
  #18  
Old 27th November 2011, 08:31 PM
efuller efuller is offline
Podiatry Arena Veteran
 
About:
Join Date: Jun 2005
Posts: 2,206
Join Date: Jun 2005
Marketplace reputation 0% (0)
Thanks: 21
Thanked 389 Times in 325 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Quote:
Originally Posted by Paul TG View Post
ERIC WROTE - This is not my experience at all. On my own orthotics a reverse Morton's extension add significantly to comfort. What do you mean by pull the foot too far medial.

PAUL WROTE- Is a reverse morton's extesnion the same thing as dropping the 1st ray? Also how much do you drop the 1st ray. Are you trying to improve fascia function with this or specifically affect the relative MP loading for some clinical reason?
A reverse Morton's extension is a piece of rubberized cork (Korex) (typically 1/8 inch) placed under metatarsal heads 2-5 with no cork under the 1st Met head. I don't know if this drops the first ray. When I stand on it there is palpably less tension in the plantar fascia and the hallux is easier for an examiner to dorsiflex. With less tension in the plantar fascia there will be less compression of the first MPJ. This is the clinical reason for the reverse Morton's extension.

Quote:
Originally Posted by Paul TG View Post
What I mean by pulling the foot too medial is that dropping the 1st ray as per the Dananberg product or creating a specific depression for the 1st met head seems to be perceived by the patient, for want of a better phrase, as over pronating the forefoot.

I would not mind this but it seem to especally irritate the medial knee and patello femoral joint. Some patients just get tib post insufficiency like symptoms. With the thick cushion some people are aware of a more medial push off but it does not seem to cause then any additional aches and pains. My observations have been that a perceived central propulsion seems most well tolerated from a comfort perspective and too far lateral not tolerated as much as too far medial.
I don't know what you mean by over pronating the forefoot. I can agree that the reverse Morton's extension will tend to shift the center of pressure more laterally, but the improvement at the 1st MPJ is often worth that. If you are worried about increase stress to the post tib you can add a varus heel effect to the orthotic that has the reverse Morton's .

I'd agree that a goal is to have relatively even load across the met heads during propulsion. I use the reverse Morton's in those feet that have worn a hole under the first met and hallux in the sock liner. In other words, if there is currently too much force medially, shifting it laterally is a good thing.

Quote:
Originally Posted by Paul TG View Post
ERIC WROTE - 3-d motion analysis. If you don't have that you could do a sagittal plane video and measure angle of foot to ground or of angle of foot to leg.

I don't think you can make the conclusion that MPJ motion has been improved when you see more ankle joint plantar flexion. To make that conclusion you would have to measure MPJ motion.

PAUL REPLIES -how can I measure MP motion? can this be done with a pressure system
Video with sandals. There are sensors that can be placed on the toes and the foot that give you a 3d position of the sensor. So if you have two sensors over the metatasrsal and one on the toe, you can not a change in distance from the sensors relative to each other that will indicate motion of the MPJ. No, it cannot be done with a pressure system.



Quote:
Originally Posted by Paul TG View Post

ps how do I put your quote in a box above my reply as you have been doing? I can see the tick box saying include quote but it does not seem to respond.
At the bottom of each post there is a button that says quote. When you click on that button all of the text is copied into your reply and at the beginning and end there is some bracketed text. The text at the beginning has the name of the original poster. You can copy the brackets and all the text inside of the brackets and paste it in another part of your reply. Each beginning bracket needs an ending bracket to get the quote box around some of the text. Or you can highlight some text and push the quote button on the tool bar. You won't get the name of the original poster when you use the quote button on the reply tool bar.

Hope this helps.

Eric
Reply With Quote
  #19  
Old 28th November 2011, 11:59 AM
Paul TG Paul TG is offline
Member
 
About:
Join Date: Mar 2010
Posts: 12
Join Date: Mar 2010
Marketplace reputation 0% (0)
Thanks: 0
Thanked 1 Time in 1 Post
Default Re: Testing functional performance of custom therapeutic footwear

ERIC WROTE - I don't know what you mean by over pronating the forefoot. I can agree that the reverse Morton's extension will tend to shift the center of pressure more laterally, but the improvement at the 1st MPJ is often worth that. If you are worried about increase stress to the post tib you can add a varus heel effect to the orthotic that has the reverse Morton's .

I'd agree that a goal is to have relatively even load across the met heads during propulsion. I use the reverse Morton's in those feet that have worn a hole under the first met and hallux in the sock liner. In other words, if there is currently too much force medially, shifting it laterally is a good thing.


Eric – Do you think that the 2-5 pad works differently to a depression under the 1st met head and if so what is your opinion as to what is happening mechanically with the reverse Morton’s extension.

Also, are you saying that when you see an insole worn out under the 1st MP and hallux you think that there is too much force medial? Would it not be expected with good 1st ray function that the 1st MP and hallux would show the most wear. Also in a cavus foot with a plantarflexed 1st ray with lateral instability these patients often do well with a pad under 2-5, which makes the propulsion more medial. This adaptation sounds the same as a reverse Morton’s extension. Does a lateral centre of mass equate to a lateral propulsion?


These post op patients report that when the 1st ray is dropped, even if the hindfoot is wedged medially that there is often a tendency for the propulsion to be perceived as too far medial. If the push off is perceived as being central this is better tolerated. To achieve this though the whole foot camber seems to need to be altered by wedging the whole undersurface of the insert.


Video with sandals. There are sensors that can be placed on the toes and the foot that give you a 3d position of the sensor. So if you have two sensors over the metatasrsal and one on the toe, you can not a change in distance from the sensors relative to each other that will indicate motion of the MPJ. No, it cannot be done with a pressure system.

Eric - What is the name of the gait analysis equipment that can do this and I will see if this available


Thanks

Paul
Thread Starter
Reply With Quote
  #20  
Old 16th December 2011, 06:43 PM
Boots n all Boots n all is offline
Podiatry Arena Veteran
 
About:
Join Date: Sep 2007
Location: Thomastown, Australia
Posts: 935
Join Date: Sep 2007
Marketplace reputation 0% (0)
Thanks: 108
Thanked 110 Times in 93 Posts
Default Re: Testing functional performance of custom therapeutic footwear

Paul sorry for the delay..busy time

Two picks for you of a MGF custom boot with a S.A.C.H, l have gone for the firm material for this client, he is very active and over 90kgs, compression is slow and should be about 30% compressed at heel strike, this varies from client to client.

And yes the SACH will be sprayed black, l thought unsprayed for the pics would be best
Attached Images
File Type: jpg SACH heel strike.jpg (126.6 KB, 19 views)
File Type: jpg SACH.jpg (102.3 KB, 19 views)
__________________
David Sutton
C.Ped.CM.Au
Facebook
My location
www.bilbyshoes.com
Reply With Quote
Reply



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Translate This Page

Similar Threads
Thread Thread Starter Forum Replies Last Post
Optimization of Therapeutic Footwear for Neuropathic Diabetic Foot Patients Using In-Shoe Plantar Pressure Analysis NewsBot Diabetic Foot & Wound Management 1 26th May 2011 02:49 PM
Custom footwear supplier Backdoorpod Australia 3 22nd March 2009 09:16 PM
Therapeutic Footwear: A Comprehensive Guide NewsBot Podiatry and Related Books 0 25th December 2008 05:06 AM
Custom orthopaedic footwear malaligned Australia 3 13th July 2006 08:01 PM
Congress to consider new bill on therapeutic footwear coverage Admin USA 0 25th May 2005 08:18 PM


New To Site? Need Help?

Finding your way around:

Browse the forums.

Search the site.

Browse the tags.

Search the tags.


All times are GMT -7. The time now is 03:01 AM.