Correcting common foot problems

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relferink

Re: Correcting common foot problems

#126 Post by relferink »

Brandon,

That sounds like a good approach for the shank. Any problems with squeaking of the orthotic over time as it lays on EVA? I'm not sure why you heat form the insole to the orthotic, is the bottom of the orthotic in the lateral to medial plane not flat? I've done similar things with an insole of Bixby, about 1/16th thick, weights nothing but strong, set the shank and cover with Thermit or something similar. I don't see why Quickform wouldn't work either. I only use this on fitting shoes. I still like a leather insole in the final shoes I make and with a leather insole I use a leather shank cover.

I dislike working over plaster. I've tried all kinds of re-enforcement techniques like reebar and electrical wire in the molds but I'm not very happy with either. Reebar works fairly well if only you can control the position of the bar when you pour the mold and not have it right on the bottom where it can get in the way of last modifications. That's actually a trick I took from O&P when was working with them in MGH. They would put reebar in all their AFO casts. It also won't work if the last doesn't come out in one piece. Still, whenever I can I will make a last from plaster but copy it to PU before I start making the shoes.

I agree on not using a full length shank when you make a customer last. Only with amputations where you have to model the missing part of the foot for appearance. On the padding end I prefer to work with localized padding in stead of a full layer of softer foam. Not in stead of the last modifications but over time the foam is going to compress some in the areas that you use to offload and the pressure is right back at the metatarsal heads. By keeping most of the orthotic firmer and only give the met heads more padding I have less problems with pressure related problems coming back.
I do very much agree with the statement
never use cushioning to disguise poor fitting
Not that it will work in the long run anyway but I do see attempts being made to cover up fitting issues. A slogan like that deserves an inspirational poster for the shop!

Just my Image

Rob

(Message edited by relferink on February 04, 2008)
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Re: Correcting common foot problems

#127 Post by large_shoemaker_at_large »

Hi Rob
Ahh the luxury of batting around theory!!

No problems squeaking.

As for the plaster I use the industrial or also called dental plaster, regular plaster of paris is to soft but that also depends on how thick you mix it.
I have used PU can't find a suppler with high density foam I used to get it from Otto Bock the 700 was nice as you couldn't hurt it. Also the toxicity unless they have changed some components I saw and industrial hygenist go wacko when they saw how the raw components were handled. I was a O&P tech for 5 years and the polyester resin and I did not agree so I'm a little gun shy.

Long shank on amputations same thoughts as yours.

As for the padding issues well I guess this pretty much gets into the "grey zone" or what you are comfortable with. I understand what direction you are thinking about the material compression. That is why I like EVA and it's different densities vs pink plastazote as that will bottem out real quick, but can give a quick view of high pressure areas. If I have and compression issues you can pop out the orthotic insole and do a quick modification especially with a diabetic foot.
Leather insoles yup but! as many of my clients are limited to 1 pair a year, they were them every day and they never really dry out. This way they can clean the orthotic and insole with water. I have had leather insoles fail from constant moisture and some get real ripe smelling. Also if you have a client with an open ulcer, body fluids do a real good job of ruining the leather. so I defer to synthetics that will not support bacteria etc.

One last thought don't forget the compression set of EVA. It may be 35 durometer lying on the bench as soon as you heat it and press it the durometer will increase. Therefore limiting compression. To bad there is no scientific way to quantify actual foot pressures before and after use. Has any light been given on the durometer of an insole when it up to operating tempurature inside a shoe closer to body temp that bench temp. or pressing temp ?

I do use poron in some circumstances ie loss of fat pad.

So many questions and so few answers
Bixby and Thermit were do you get it?

Regards
Brendan
The only thing missing is a couple beers to keep this discusion going. oh well a small price to pay for internts distance shortining. Keep the thoughts coming!
relferink

Re: Correcting common foot problems

#128 Post by relferink »

Brandan,

We'll have to hold off with the beer talk till we get to sit down, maybe at this years HCC meetingImage?
Is it the Otto Bock 700 foam (617H41=...) that's no longer available? I haven't ordered some lately but that would be a shame if they stopped selling that. I actually liked the Degussa foam better when I worked with it in Europe but I can't find that on this side of the pond. I read that they are building a large new plant in the southern US but it's not clear to me if they will be making PU suitable for lasts. We'll just have to wait and see. It is not nice stuff to work with, you have to use it in a very well ventilated area and not breath the fumes till it's cured. Best thing to use it outside if at all possible. I don't know that there is a non toxic version available.

I don't recall that I ever tried dental plaster, at least not by that name. I'll see if I can get some around here and try it. Thanks for the hint.

I agree with the difference in density once you heat mold EVA. Getting an accurate read would be difficult as it depends on the base durometer, all EVA as sold is always + or - 5, the temperature and duration it's heated for, the pressure its molded with and the shape it's molded to, whether there is stretch or compression in the material.
I know from experience that EVA orthotics milled in stead of heat molded do compress more quickly and seems not to to last as long.

I don't get too many customers with open wounds but in those cases a man made material is indeed better. As long as there are open wounds there often is swelling and drainage, any shoe made for a case like this would in my opinion be a temporary shoe and a final shoe will have to be made once the wounds are healed up.
I definitely prefer Poron over an open cell foam like plastazote that bottoms out very quickly. The only advantage of plastazote is as you mentioned the ability to show high pressure spots after a short period of wear.

Bixby is a celastic type material, I will have to look up the manufacturers exact name for the stuff I get, it's a non-woven that can be formed with heat or solvent. For insoles I do neither, just lay it under the orthotic. This material was popular for counters about 15 to 20 years ago in factories. I still see it used in factory shoes on occasion. I buy it from the Bixby Corp. in Newbury, MA. They do require a large minimum order so once you buy some you'll be set for about a decade, at least I amImage. Be happy to send you a sample if you like. Thermit RX is a stiffening material. Atlas Intl. in CA sells it, I think Frankford leather out of PA does as well. Not sure about any north of the border vendors.

It's getting late here in the East and tomorrow I have a busy day so I'm signing off for the night. Good info in your posts, keep it coming.

Rob
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Re: Correcting common foot problems

#129 Post by large_shoemaker_at_large »

Hi Rob
Seems we are workin' in the same direction. I do some work with bad diabetic feet and yes some shoes are temporary.

I am going to make another pair of shoes for, around the house, for this gent. But a Pedorthist I work with a couple days a week is going to make them. I am just roughing out the orthotic for him as his press won't take a large foot cast. I will keep you apprized on the fun.

If you want to send a sample sure, never closed to new materials and methods. send me an email.

Regards
Brendan
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Re: Correcting common foot problems

#130 Post by sean_oneil »

Hello all,

A consumer oriented program aired in Canada last night. I think it has some relevance to the members of this forum. It was about a thinly veiled scam involving qualified people recommending that patients/victims buy orthotics that are sold through a channel of franchisees who are usually chiropractors.

A significant part of our business is a line of stitch down shoes that we custom fit to our customers. We have about 4 men's & 5 women's styles that we will sell based on us measuring their feet personally ( the usual tracing & measurements ). The customer gets to pick the style & leathers and there is an unconditional guarantee that the shoes will fit and be comfortable. We do not accept payment prior to building the shoes and having a happy fitting. This business model has served us well but there is a fly in the ointment - specifically the appearance of poorly fitted, badly built orthotics. Obviously orthotics are part of the business, there are more of them appearing every day and maybe that is to be expected with an aging population. Early on we realized that accommodating orthotics was going to be a necessary evil, and a useful service to our clients. As time went by we kept hearing about orthotics that would only work in shoes that the orthotic supplier would be happy to sell you. Trust me, when you see a few hundred pairs of orthotics a year, it is easy to tell which ones have been made by skilled & ethical technicians, and those that haven't.

So, if dealing with orthotics is part of your business reality, I urge you to take a look at the following link:

http://www.cbc.ca/marketplace/

It will only be an active link until the next week. When it's gone, it's gone.
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Re: Correcting common foot problems

#131 Post by large_shoemaker_at_large »

Hi
I didn't see the mentioned program but it was quite a topic at work yesterday. I read the website and got a better perspective. I have made shoes and orthotics for 30 years. I have seen stuff sluffed off as custom, I have seen terrible custom orthotics, I have seen custom orthotics that are identical and the feet arn't, and many that are milled to sit flat on a table with no allowance for a heel and to many that just won't fit in a shoe.

To many people have hopped on the band wagon and see it as a cash cow. Most people wouldn't get them if insurance didn't cover them and even if they don't fit/work people don't usually complain they just wait a year and get another set.

Any device must fit the client and the shoe and work together

I have been asked to make a shoe to fit the orthotics. to me this is like buying a chev and refitting it to a ford. No harm intended here Sean as I understand were you are coming from. I notice that the orthotics made are for mild foot conditions I rarley see any people tackling the real bad diabetic foot or something a computer and softwear just can't handle. The Computer thing is greatly over rated. I have used various force plates and in shoe systems in eduational realms. I can see the benifits to a point. But most systems seem to be designed to woo the client and remove any technichal skills needed.
I don't care about debating who is qualified Orthotics vs podiatrist etc BUT if you have no knowledge of how a last is made and then a shoe over it you can't make a good orthotic period.

Unfortunatly the insurance companies have been the worst enemy to the consumer and the provders. They started to cover items and had no idea what they were covering. Then the various rules of who could prescribe and provide started to change faster than one could keep up to. If the insurance companies would do a follow up with the client to gauge the level of client satisfaction AKA Quality Assurance they could soon fiqure out who provides a service equal to the money spent. Also being a prescriber and dispenser does put one as suspect for conflict of interests. I have also been asked by prescribers for a " referal fee" to which I stated "that is unethical and I don't need your business". so maybe that is why I drive an old truck!
Being a good craftsman and a good businessman do not neccessarly go hand in hand, But a happy customer and a hug is an intrinsic reward money can't buy and I like to sleep well at night.

Guess you see this has been a Bee under my bonnet for a while!
Regards
Brendan
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Re: Correcting common foot problems

#132 Post by gshoes »

Hello all,

My daughter has marfan syndrome and one of the many issues for her is footwear. She wears a womens size 15 or 16. She is flat footed and needs Orthotics. I have decided to make her a set of lasts so that I can make girly style shoes for her with orthotics built into the shoes. Her current orthotics are made to fit in her everyday mens gym shoes so even if I make her a pair of womens shoes the profile of the custom orthotic does not fit in this custom shoe. So here is what I did. Or what I did wrong?

I have created a last for my daughter that is shaped to the contour of her foot that has been placed in the proper position for a suitable arch. A simple cast was made and then I poured mixture of bondo and polyurethane resin into it and duplicated the last bottom and instep according to this contour.

My question is how do I ensure that the sole is built up so that the foot is now held squarely on the ground and not twisted. I realize that I can use a belt sander to get it flat but I have a feeling that I need to install Frankenstein neck bolts so that I can level the beast before I put a sole on it.

I am also very confused in why we take a measurement of the instep around the foot and then construct a last that on a normal foot, the foots arch does not contact shoe. At least that is what I am thinking because the foot bed on most shoes is relatively flat.?

On my daughters shoes, I have built up the arch to be strong with polypropolene molded against the mold that I made. Does anyone have any better material and sources for that material to build up the arch in a lightweight and shock absorbent way. She has mentioned that the shoes are hard but she also notices this in her gym shoes, maybe to a lesser degree.

I have been trying to build up the insole prior to lasting the shoe withy vegtanned leather so as to hide the internal thickness of the shoe. I don't know if this is how it is supposed to be done but it worked fine in her last shoes. Except they are heavy. The sock liner is contoured and she never has to replace an orthotic. I am just concerned that there are some special points that I need to be checking so that her pronation is corrected. I am not even sure if that is what it is called though. I just don't want to cause more problems for her in my quest to help her.
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Re: Correcting common foot problems

#133 Post by gshoes »

Whoops. I forgot to downsize the pics. Sorry
Geri
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Re: Correcting common foot problems

#134 Post by large_shoemaker_at_large »

Hi Geri
Well go are going full out! If you can read an earlier post of a pair of boots made with the supine foot. Well the basics are the same but elevating the medial side for this foot type. If you make a shoe from scratch keep the hard reinforcment for the insole. I use EVA of differnet desities for the orthotic insole, Some cushioning and good control. and no need for the Frankinstein Bolts. Remeber the "gentle art" one should not break a sweat to make a shoe.
I'll try to take a pic of a last built for a similar foot so you can see what to shoot for. Don't forget the fore foot as quite often a higher medial ball helps that foot from rolling in to far to achive "toe Off".
This has a couple advantages you can shape the orthotic insole so the feather line is more light looking, while keeping the heel in nuetral and the feather line parrell to the ground for astheics.

I'll try to get a pic asp
Regards
Brendan
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Re: Correcting common foot problems

#135 Post by large_shoemaker_at_large »

Hi Geri

Got a photo of the last and some casts I just poured.
Last, notice the medial heel line starts up early in the heel and progresses to the ball. You are trying to "romance the foot over" not force it into position. The medial fore foot when the orthotic is finished will be approx. 1/4 inch thicker that the lateral side as to in the front inside of the heel.
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The cast I marked the heel 90 degrees to the ground.
again notice the differance from the heel to ball. This is an extreme flexable fore foot.
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This cast was taken face down in the theoretical Sub-Taler neutral position.

Now starts the debate how to address this. For this person I will hold this foot in this position, using a full length orthotic . Using a sorter cover about 45 durometer after pressing and a 60+ durometer shell if needed.
To make a shoe. press the EVA over the last, shape the orthotic insole, grind your tread/featherline to similate a normal shape. Then make the pattern, orthotic included. Last over a firm shank and insole to the ball of the foot and a flexable forepart. Cement or stitch as needed.

If you can mount you belt sander to a bench and bring the shoe to the paper
A lot of info stuffed into a small space, try making a fitter
ask more questions, Rob please help if my description is too off with out slinging latin .
Regards
Brendan
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relferink

Re: Correcting common foot problems

#136 Post by relferink »

Sean, Brendan,

Firs off all thanks to Sean for sharing that link. I wish I could safe the video for future reference. I may just have to order it from the station.
I think many of us who make orthotics for what they are intended to, a device that corrects a biomechanical miss alignment feel the same frustration with those that approach this subject solely as a money making proposition.
Orthotics are a blind item in that there are many different approaches and levels off success. For many customers a cheap over the counter device can make a world of difference. They do not need a custom device. Others really need a custom device but end up with at best a customized orthotic that is not nearly as functional as it can be. To the customer it is however an improvement from their prior condition and if they do not have to pay out of packet they are not likely to complain.

I found it telling that the rep from the orthotic group would not allow cameras behind the scenes. Probably because all they do behind the scenes is take a pre-made orthtic, peal off the "made in China" label and put on a different label with the customers name on it. A custom label that isImage. If they truly had a unique process it would be patented and protected!

Just like Brandon I have been asked to make shoes around an existing orthotic but refused. Not because I can't do it but when you make a custom shoe you can make an orthotic footbed build into the shoes that is much more functional than an orthotic for a mass produced shoe.

Insurance? don't get me started on that. The way the insurance companies define covered items and the procedures to collect require an accountant and a law degree. If you have to pay for those there's no money left to make a good orthotic.

Just my Image

Rob
relferink

Re: Correcting common foot problems

#137 Post by relferink »

Geri, Brandon,

I much agree with Brandon. I really don't have all that much to add.
My experience is that a stiff plastic like Polypropylene is under certain circumstances good for orthotics that are retrofitted into mass produced shoes but too hard when you make a fully custom shoe. Like Brandon I prefer EVA or cork for a custom footbed as it allows for better shock absorption and control of the foot. For custom shoes I work a lot with both ground cork sheets as well as thermoplastic cork for the orthotics. I mold my orthotic to the bottom of the last, than grind it to resemble the bottom of a regular last, put on an insole and make the shoe as you normally would. If you don't glue your insole to the orthotic it will be removable and can easily be adjusted.
Probably not all that different from what you described by building it up with veg tanned leather but leather will make it heavy, cork or EVA will keep it much more manageable.

A belt sander is not always the best tool to use. If you are looking for a small and useful sander Google the Sani-grinder. The prices that come up are retail prices. Last time I bought one a couple of years ago I payed about half but you may need to buy it as a business as not all dealers are set up to sell to the public.

Your lasts look good and based on the pictures you posted you are really on the right track. On the last; be careful not to make the heel too round, by adding a feather line you keep the foot from being pushed forward to much once it starts bearing weight. Keeping it as round as you have it will make the shoe gap in the back.

I think (and hope) this addresses your most pressing questions. Your definitely are moving in the right direction. Once you put an orthotic to this last you should be able to get a fitter made up for your daughter to wear, this will give you a good idea of how it all is going to work out.

Rob
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Re: Correcting common foot problems

#138 Post by gshoes »

Rob and Brendon,

Thanks for your help.
Brendon, I have more questions for you but I do want to refer to my bible {"Foot Orthoses, Principles and Clinical Applications" by Kent K. Wu} before I formulate my question ('s)

Can you tell me what exactly is EVA and where and in what form can it be purchased?

I have made two pairs of shoes with these lasts. The first was a 4-5 ounce lined, lace up shoe that seemed to fit fine. It had a 3 ounce veg tanned heel counter and I didn't notice a heel fit problem. But I wasn't the person wearing the shoe.

The second pair was a quickly thrown together pair of pumps/slippers with no heel counter. The vamps were 3 to 4 ounce metalic chrome tanned upholstery leather. The lining was a 1 .5 ounce wedding white pig skin. The shoes were worn without stockings. Now that you mention it I do remember a bit of a baggy look arond the heel area. I attributed this to no stockings and no heel counter. Now I think that the heel counter was hiding the design flaw in the lasts.

I will make some adjustments to the heel profile. My first attempt at the last produced just the opposite problem. can you tell me if there is a formula for figuring out this curve that I missed.
Image
Geri
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Re: Correcting common foot problems

#139 Post by gshoes »

Rob and Brendon,

Thanks for your help.
Brendon, I have more questions for you but I do want to refer to my bible {"Foot Orthoses, Principles and Clinical Applications" by Kent K. Wu} before I formulate my question ('s)

Can you tell me what exactly is EVA and where and in what form can it be purchased?

I have made two pairs of shoes with these lasts. The first was a 4-5 ounce lined, lace up shoe that seemed to fit fine. It had a 3 ounce veg tanned heel counter and I didn't notice a heel fit problem. But I wasn't the person wearing the shoe.

The second pair was a quickly thrown together pair of pumps/slippers with no heel counter. The vamps were 3 to 4 ounce metalic chrome tanned upholstery leather. The lining was a 1 .5 ounce wedding white pig skin. The shoes were worn without stockings. Now that you mention it I do remember a bit of a baggy look arond the heel area. I attributed this to no stockings and no heel counter. Now I think that the heel counter was hiding the design flaw in the lasts.

I will make some adjustments to the heel profile. My first attempt at the last produced just the opposite problem. can you tell me if there is a formula for figuring out this curve that I missed.
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Geri
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Re: Correcting common foot problems

#140 Post by large_shoemaker_at_large »

Hi Geri
Get your daughter to stand on something the same as the heel height - sole and trace the back of the heel to a peice of card board and trim the top part of the heel in to match the profile and then just a "tich more". The curve depends on the heel height and type of shoe. The last seems generous in proportion so you could hollow out the ankle area to get more "tension" along the shoe. In my humble opinion you could start with a higher heeled last.
EVA is avalible at many shoe finders now or Prosthetic suppliers. My best supplier is Vittoia Pheonix from Ontario Canada. You probably have some thing closer. It glues well with barge/helmifix

I saw plaster and bondo You are not to far off having the wear with all to make a custom last. You can make a good last from body filler it will stand the rigours of shoemaking and is easy to modify.

If you can get a grinder keep in mind a smaller wheel 3-4 inch 4 wide diameter is what you need to get into the tight spots and still make a smooth surface on the sole.

Do you have a vacuem press ? There are inexpensive bags for making skate boards and would work for forming EVA etc. Check out Lee Valley Tools on google.

Regards
Brendan
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Re: Correcting common foot problems

#141 Post by gshoes »

Brendan,

Thanks. When you add that I could start with a higher heeled last, are you referring to the hieght of the heel of the shoe or the top of the last in the heel area.

As far as the grinder goes, I currently am using a Landis 400 finishing machine. I has 1.5" wheels and 4" wheels if I remember. I am quite happy with this beast. It almost killed me getting it here and it comes with a vacumn system built in. A shoe repair man sold it to me for $150 and told me that I could move it myself easily. Thats another story though I did it with the help of a friend.

I am currently trying to make a small vacumn table to form the polypropelene sheets over my plaster mold of the arch. I am told that a shop vac hooked up to it will work? Is this EVA stuff similar to polyproplene?
Thanks again.

Geri
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Re: Correcting common foot problems

#142 Post by gshoes »

Brendan,

In an earlier post you stated,

" Don't forget the fore foot as quite often a higher medial ball helps that foot from rolling in to far to achive "toe Off".

Can you explain in little more in detail what you mean by this?

Also in your pic of the plaster foot mold upside down, that is marked with a 90 degree to the ground. You stated " The cast I marked the heel 90 degrees to the ground again notice the differance from the heel to ball.". Is the square that you are holding up showing me the difference between the medial and the lateral sides of the forfoot or did I miss the point completely?


Geri
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Re: Correcting common foot problems

#143 Post by large_shoemaker_at_large »

Hi Geri

Landis 400 with a little care it will out live both of us. Yup understand machines as I pinned my self unloading an old cast iron Jointer.
EVA is a foam product Comes in many densities (shore) and colors, thickness. Off the top like vibram crepe soling pyramid top.
Vacuum press are easy I made mine with a hole in the top to do full foot casts and a peice of 1/4 ply for orthotics. Check out the local surplus shop for a vac pump as some times thy don't know what it is. do a google on some Ortho sites and see the Gast pumps.

As for the casts and the square, were showing the planar differance from medial to lateral in the fore foot as compared to the heel, as this foot is flexable enough the heel will come back to neutral AKA 90 degrees. As for the last I was refering to heel height under the heel.
I want rob to jump in soon, the higher the heel to say 7/8 inch will give a better result. Lessens the strain on a probably tight rear muscle group and would reduce the amount of fore fore correcction needed getting back to toe off.
If you can stand behind your barefoot daughter and get her to get up on her tip toes and watch the heels and see if they move inwards, now put a 1/4 to 3/8 wedge 4 inch long with the thick part under her big toe joint and repeat the tip toe and note the differance between the two movements. the lower leg should roll/twist in less with the wedge.

The theory that you have preloaded the fore foot so less effort is needed to achive a "locked" foot to achive toe off. or lessen internal tibial rotation. If anyone can explain different or better please jump in.

With some work you can accomodate an orthoic insole and not add much over 3/8 to over all depth. and add a bit of a rocker sole at the same time. Easily hidden by style or construction.

I'm go rooting for a presentation I did on casting at a PAC conferance many years ago, see if I can find it and help explain some more.

Regards
Brendan
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Re: Correcting common foot problems

#144 Post by gshoes »

Brendan,
Ok I think that I follow what you are saying. I will get her up on her toes and have a look see. Thanks so much for all of these pieces to my puzzle.
Geri
relferink

Re: Correcting common foot problems

#145 Post by relferink »

Geri, Brandan,

EVA stands for: Ethylene Vinyl Acetate. It is a copolymeric member of the polyolefin family derived from random copolymerization of vinyl acetate and ethylene. In English: it's a closed cell foam that is frequently used in midsoles for athletic shoes. It has a good balance of cushioning, weight and durability. It can be bought from any finder. If you don't know of one in your area check with a local shoe repair who their supplier is. There are a number of Colloquy readers from the greater Chicago area that can probably help you with some names and addresses.
EVA comes in sheet form in any thickness you want and the two most common types here in the US are Cloud, a 35-40 A shore durometer and Soleflex a 50-55 A shore durometer. It's available in a variety of colors.
Cloud and Soleflex are trademarks so a different manufacturer will call the same thing by a different name but they are all EVA's.

A shoe without a heel counter is a no-no for the foot your working on. It will really do nothing, placing an orthotic in that shoe will just allow the foot to slide off to the side and be useless. This type of foot is better off not in slipper type footwear.

The picture of the last up against he carpenters square does not mean much as the last is not set to heel height. Just based on the picture I would say that the longest part of the heel needs to be lower but I don't see that problem on the other pictures of your lasts you posted so I assume it has more to do with the last not being set to heel height.

If you compare the last
7089.jpg

the the image of the foot
7090.jpg

you can see the difference in the rounding at the bottom of the heel. They do not have to match totally but you should not round the heel as much as your cast that is taken non weight bearing.

I don't own a copy of Mr. Wu's book so I for one can not comment on that specifically.

Rob
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Re: Correcting common foot problems

#146 Post by relferink »

Oh, I forgot, the top of the last comes in too much to my liking. I would expect to see a shape closer to this:
7092.jpg

Apologies for the very rough sketchImage.

Rob
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Re: Correcting common foot problems

#147 Post by gshoes »

Rob,
I thank you very much. I never even thought to place the last on a heel piece. I don't know why that it had never occurred to me before to do this. Also it makes so much sense about not keeping the bottom rounded. I have been preoccupied with cupping the heel the way it is naturally shaped that I forgot what 230 coming straight down on a heel can do to flatten it out. It really helped seeing the foot picture and the last compared side by side. I think that I have been way to close up to see this. Thanks so much. I will need to go back to the drawing board. Your expertise and experience is greatly appreciated.
GERI
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Re: Correcting common foot problems

#148 Post by relferink »

All,

A comment made by our friend Al Saguto in "One Last Question" caught my attention. Al was able to cramp a lot of very good information into that post. He claims he was only on his first cupa, must have been some good stuf in thatImage.
I moved it out of the “One Last Question” topic as I like to go a little more in depth on the biomechanics of it all.
I have not yet located the discussion of years passed Al referred to but I'm very interested in re-reading. Any clues where I can find it as the archive it getting so extensive? If it's been 7 or 8 years it may be on the archive CD? I don't' have that handy right now to check.
Another old hand recommended that you can clip (pinch) the great toe, or the small toe somewhat. I'm not so sure, as I've observed a host of minor (to extreme) problems that were caused by clipping the great toe--from pronation, to walking-over on the lateral side, not to mention calluses and bunions, etc.


Looking at it as someone that deals with "problem feet" more than "average feet" I like to add a little more perspective to the above. To me the toes are the mirror of the functioning and the mechanical state of the foot. Most foot problems originate in the rearfoot and/or midfoot. The toes "amplified" the condition by showing symptoms that are otherwise not always easy to recognize. To clarify I have some examples:

A bunion is rarely caused just by pushing the big toe laterally. If this was the case, the practice of using a little splint to pull it back, the ones that Velcro on and can be bought in the drugstore would be much more effective and be suggested in stead of surgery. Sure, high heeled, narrow women's shoes are a cause for bunions but that has much more to do with the overloading of the forefoot, stressing and damaging the first Metatarsal Phalangeal Joint (big toe, metatarsal joint) that just pushing it over in a too narrow toe box.

Excess pronation in a foot is often very clearly indicated by a callus on the bottom edge of the medial side of the big toe.
7094.jpg

This is only a symptom of a process that often starts at heel strike and mid stance. The foot is not able to recover it's position before toe off, causing the bone structure in the foot not to “lock” properly to support the body during toe off resulting in stress and ultimately damage in the MTP joint and the a pinch callus as a tell tale sign. Just pinching the toe by making the last slightly narrower will not cause a callus like this and keeping the last wide enough so the toe does touch the shoe will not help the callus disappear. In fact making the last wider in the toe may cause one to make the last wider in the instep to achieve an acceptable look, this will make the pronation problem worse.
Unless you control the foot at heel strike and mid stance and doe not allow the over-pronation to happen the callus will continue.

Hammertoes are often caused by the "failure" of the arch that runs across the ball causing too much pressure on the metatarsal heads. The toes press down to offload some of the pressure of the metatarsal heads and if they do this long enough and forceful enough they will "freeze" in this state, creating a hammertoe. A shoe fit too short will rarely cause a hammertoe. Sure it will not help the cause and as stated many times before on this forum, if you are going to fit them wrong, fit them long but just giving the toes more length in a shoe will not resolve the problem. Building metatarsal support in the shoe will over time relax the toes and even though it's uncommon for the toes to straighten back out, they do not progress much further.

Once you have taken care of the cause for the toes to do what they do you have to make an informed decision if the toes still need as much width as your tracing shows. Answering that in a general sense is not possible, every case is unique and the decision on how much fit to sacrifice for looks is up to the shoemaker. As much as I hate to say it, if the customer does not like the look of the shoe they will find something wrong with the fit, if they like the styling they are willing to put up with a certain level of pinching.

Thought I'd share these thought with you all.

Rob
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Re: Correcting common foot problems

#149 Post by dw »

Rob,

I couldn't help but be interested in your analysis if only because I think I may be the "old hand" that Al referred to in the above quote.

I build on higher heels than you probably do and that may give me some leeway but in 35+ years of building boots, I have regularly seen the bottom paper from a last cover the footprint/pedograph very precisely in every location except the first toe. There I often use a last that allows a bit...maybe 20-35%...of the the big toe to peep out from under the perimeter of the bottom paper.

This may be blasphemy in some quarters...certainly Al isn't happy with the notion (correct me if I'm wrong, Al)...but I see no ill effects. No complaints, no long term effects.

To further underscore the point, my own foot is nearly as straight as a baby's foot all along the medial side. You could run a ruler from the side of the heel to the end of the first toe and it would be in contact with the foot the whole length. I do have a low arch and some would say I even pronate a little bit although I don't have any adverse symptoms, and I print a "wide/normal" arch. I have worn boots with the kind of "clipping" toe described above for nearly 35 years as my only footwear (I do wear moccasins on weekends while lounging around the house) and have never experienced any discomfort nor has my foot changed shape. The big toe has not shown any signs of migrating laterally or opening up in the joint, either.

I don't doubt that there are people who do experience problems even when the lateral pressure is slight. But, thankfully, I'm not one of them. And the great majority of my customers are similarly fortunate.

All that said, I was extremely interested to read your comment that most of these problems begin in the rear or midfoot. I don't know much about it or how that would change a person's need or preference for a last that doesn't clip at all. Maybe not at all, but I thank you for your insights as they have ratified many decades of experience for me.


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Re: Correcting common foot problems

#150 Post by relferink »

DW,

The post Al put up in “One Last Question” nearly triggered the idea to elaborate on “reading the toes” if you will. This post was not to agree or disagree with either Al or you per se. As put in my post, once you know the state of the foot by “reading the toes” you have to make an informed decision on how tight you want your toebox to be. Every case is individual and if you understand the larger issue at hand you may be able to offset it in the rearfoot / midfoot design of your last and make the toe pinching into a non-issue.
This may be blasphemy in some quarters...certainly Al isn't happy with the notion (correct me if I'm wrong, Al)...but I see no ill effects. No complaints, no long term effects.

You are correct in most cases, depending on your customer base probably 90% or more of the time. Still, wouldn't it be great if you could recognize the other 10% and know not to clip the toe for them? That's where you should be able to achieve if you pay close enough attention to what the toes are telling you.

Specially for readers that are not able to draw on many years of experience there should be a healthy reluctance to compromise the outline of the foot. Time and experience will teach you how far you can go in brining in the toe but if you fit them wrong, fit them wide it this caseImage.

Rob
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