Physical or digital models of the foot for orthosis manufacture

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This study got me thinking: http://www.jfootankleres.com/content/3/1/19

If we took the cost of digital scanners out of the equation, how many people would still prefer to use plaster of Paris or foam boxes to capture the foot for the manufacture of a foot orthosis?

As ever, please vote in the poll and let me know your reasoning.

P.S. I tried to edit the poll to add a third option of both, but it was too late.

 

Do we assume that the same foot capture is made by both. ie one thing besides price thats holding me back at the min. is the qualilty of ´foot capture´ of digital scanners

 

Assume present technology, assume I'm offering to give you the scanner of your choice from the current market place- would you use it, or would you use plaster of Paris / foam box?

Why would you choose to use one over the other?

p.S. which scanner would you choose and why?

 

At the moment I would stick with the plaster methods. Probably a little stuck in my ways. I also know what I´m going to get and from reading posts from people such as Phil Wells the scan method will not yet give me those constant results. It also appears to me a little easier to manipulate the plaster cast - so maybe cast scanning is where I may end up rather than direct foot scan ?

But maybe I´m a little stuck in my ways, to make that jump, yet.

 

Were you taught to use scanners at Podiatry School?

Question: which podiatry schools provide practical tuition to undergraduates on foot model capture using one or more digital scanner systems?

If I manufactured and/or wanted to sell scanners, I'd loan one to every school in the country or at the very least give free training days to undergrads.

 

No not taught to use a scanner - doubt there was foot orthotics made with a scanner in 1995. But there are lots of things I use daily that I was not taught at school.

When we were discussing the orthotics lab set up here for the school, It was one of the components that I wanted - physical v´s digitial orthotic manufactor, but we only discussed that it was a good idea and then that was it.

 

What about you, reading between the lines with some of your posts re direct milled or pressed devices have you gone back from digital to physical ?

 

Had a digital scanner for a year and although patients thought it was great and very swanky, I had to re scan on several occasions because the lighting was poor(I suspect things have moved on), my computer would peiodically crash etc etc.

It tended to produce very generically shaped devices as I had no control, other than filling out a prescription form after taking the scan.

Also, I had several occasions where I looked at the scan and thought - well that doesn't quite look right - and I couldn't do anything about it. Now I use POP or foam boxes and tweak almost every cast before going to the lab so that the minimum amount of work from the lab is required.

I'm sure the scanners are better now but that is my rather poor experience

Robin

 

I've never captured a foot impression digitally for a foot orthosis (I've done it for orthopaedic shoes), I've scanned-in plaster casts for foot orthoses. I'd like to move away from plaster completely and embrace the digital revolution. Personally, I think that for the vast majority of cases (I see), digital capture and CAD/ CAM manufacture is the way forward- but there will always be the odd exception.

Here's what I would like to see in the not too distant future: labs providing scanners that are capable of non-weightberaing through to weightbearing captures of the foot, and desk-top milling machines capable of producing plastic and foam devices. I scan in a foot, e-mail the file to the lab along with a prescription form. They create the device digitally and e-mail the file for milling. I lease / buy the hardware from them/ a.n.other and buy materials from them/ a.n. other to manufacture the devices. If I'm locked to their lab by the hardware, you might even expect it to be loaned for free. I pay a click fee for the orthotic design and get it returned in an agreed time- price may vary on turn around time. Just one view of the future.

 

Phil and I email discussed a method where I would scan the cast - design the device - email the file - Phils lab would mill the device and ship back to me. The lab would also review the device before mill and ask questions of my design if there was holes.

We never got to discuss in person due to volcano activity, maybe next year when I come to the UK for some CPD activity, and if the biomechancis summer school is not on the 25th/26th on June.

 

The key is in the CAD system, in order for Johnny practitioner to be able to use it, it would have to be stripped down and simplified, the labs should have the best CAD systems, i.e. full delcam, solidworks etc and have the skilled people to use it to its full potential. They do it day in day out- they're going to be better than you or I at doing it.

OK, so bigger/ better milling machines will be quicker / more accurate, but at the end of the day that is just dumb hardware and technology advances so it gets quicker and more accurate on the smaller scale. The human skills need to be learned. In order for you to send the design to Phil or anyone with a milling machine, you need to be able to buy and use the CAD not as easy as might think. So two option, dumbed down CAD or slower milling? How many devices do you need per day? Are two slower millers better than one dumbed down CAD and the manufacture and shipping costs?

 

I've had this choice. For a while I had both a laser scanner and the old tech versions available in the clinic.

After a brief flirtation with the digital revolution, I reverted to the Foam.

The scanning certainly impressed the punters. But the we came to the matter of modifying the cast. With foam, if I want a bit more THERE or a groove THERE or a coutout THERE I can do it, myself, in clinic, with the patient in front of me, with my thumb. If I want to specify exactly where, how deep and what angle a skive is, I can mark that on the foam also.

With the cad cam, there was the facility to do all of that (I suspect). But it was less intuitive and much more time consuming. With foam, the shape of the inside of the box is the shape the insole will be. Simple. What I see is what I get.

Also I like to use a broad palette of materials. I like polyprop, EVA, plasterzote, poron, poron 92, and assorted laminates thereof. I like the option of a high medial wrap. Again, I suspect someone clever could do all of this with CAD, but I'm not that person.

So call me a luddite if you will, but I'm a control freak. I like to see and know EXACTLY what shape my device will be, and I can't do that with CAD.

 

Is it just a training issue? I.e. the first time you made a plaster cast it was probably rubbish... (is that why you gave up and went for foam boxes ;-))

 

I would like to move to digital (not that i have any hands on experience with 3D digital scanners)

From above threads, patients love them. My patients always ask Whats new in orthotics? people want technology.

I am using POP, i feel it gives the most accurate representation of the foot (in my opinion). But its messy and takes around 15 minutes from set up to clean up.

I have used cad cam orthotics and have no problems with them (except price) and using a digital scanner will lock you to a particular lab, this i feel is probably the major drawback.

 

A good point - time is money and the longer time spent learning the CAD systems would be very large compaired to a couple of mins. etc mill time. But then there the time and money spent keeping the mill up and running - which should be covered in your hire costs. Also another advantage to have a mill at the clinic, could be a simple system for things such as heel lifts.

 

Rude man . I used POP for 3 years before I started using foam.

But yes I think there is a big training issue with all three systems. I suspect with the right training you can get what you need from any of them.

Mind you, with the right training you could probably whittle it from a block of pine...

 

I'm currently looking at the scanner from Paris orthotics. I believe this has a two lazer and one camera system which apparently triangulates as compared to two camera systems. Not sure how to deal with the flay interface for capturing ff valgus, plantar flexed first rays etc but will report back after September 30.

 

Sorry, FLAT interface

 

As most of you know, I use an AMFIT Digitizer to capture my digital scans. It would be difficult to be used for non-weight bearing scans, but not impossible.
I use partial weight bearing sitting scans with knee and ankle at 90 degrees and a modified technique to find STJ neutral. I explained this technique in an article for Podiatry Today online.
I think AMFIT's software is far superior to any other scanner that I've seen. It really does allow you to add accomodations, trough's (which I use for cutouts at the first ray) medial heel skives or lateral and total device in / eversion as you wish. There really is not much it cannot do.
They, AMFIT are now making polypro devices as well and we've had great results adn feedback from our patients in the initial testing with my patients.
I would like to be able to make the polypros in the office, but that is not possible at this time. For the full length EVA devices we have a Cad Cam table top milling machine that works great.

Same old stuff from me. Total control would be great for those of us who have controls issues.
Sincerely;
Bruce Williams

 

Thats me

Actually, to be fair, I've had a play with the amfit software and I found it pretty intuitive and easy to use.