!
Board Review Orthotics & Prosthetics

Writing Orthotic Prescriptions

Scott Marshall,

Scott Marshall reviews the numerous types of orthotics that can be used to improve foot and ankle function for the specific needs of your patient.

CPME (Credits: 0.75)

PRESENT e-Learning Systems has designated
an unrestricted educational grant from
to support this online education activity.
  • CME Progress
  • Pre-Test

  • View Lecture ( CPME Credits: )

    Lecture Transcript

  • Post-Test

    Requires: Pre-Test, View Lecture
  • Survey

    Requires: Pre-Test, View Lecture, PostTest
  • Certificate

    Requires: All Content Above
Method of Participation

Complete the 4 steps to earn your CE/CME credit:

  1. Complete the Pre-Test
  2. View the Lecture
  3. Complete the Quiz (Min. 70% Passing Score)
  4. Complete the program Survey
Goals and Objectives
  1. Understand how to order orthotics to meet the specific needs of the patient
  2. Describe how surgery, orthoses, and shoe therapy can all be used to improve foot function
  3. Understand the different types of orthotics available and which conditions are best treated with each
  • Accreditation and Designation of Credits
  • CPME (Credits: 0.75)

    PRESENT eLearning Systems, LLC is approved by the Council on Podiatric Medical Education as a provider of continuing education in podiatric medicine.

    PRESENT eLearning Systems, LLC has approved this activity for a maximum of 0.75 continuing education contact hours.

    Release Date: 03/16/2018 Expiration Date: 12/31/2018

  • Author
  • Scott Marshall,

  • System Requirements
  • To view Lectures online, the following specs are required:

    • PC Pentium-III class or better processor
    • 256MB minimum of RAM
    • Cable or DSL broadband Internet
    • Browsers must have javascript enabled. Most browsers have this feature enabled by default.
    • Adobe Acrobat Reader (Free) to print certificates
    • Supported Browsers:
      • Chrome
      • Firefox
      • IE 10+
      • Safari
      Supported Mobile OS:
      • Apple iOS 4.3+
      • Android 2.3+
      • Honeycomb 3.1+
      • Blackberry Playbook
  • Disclosure Information
  • It is the policy of PRESENT e-Learning Systems and it's accreditors to insure balance, independence, objectivity and scientific rigor in all its individually sponsored or jointly sponsored educational programs. All faculty participating in any PRESENT e-Learning Systems sponsored programs are expected to disclose to the program audience any real or apparent conflict(s) of interest that may have a direct bearing on the subject matter of the continuing education program. This pertains to relationships with pharmaceutical companies, biomedical device manufacturers, or other corporations whose products or services are related to the subject matter of the presentation topic. The intent of this policy is not to prevent a speaker with a potential conflict of interest from making a presentation. It is merely intended that any potential conflict should be identified openly so that the listeners may form their own judgments about the presentation with the full disclosure of the facts.

    ---

    Scott Marshall has nothing to disclose.

  • Lecture Transcript
  • TAPE STARTS – [00:00]


    Harold: Our next speaker is Scott Marshall who has been involved with the laboratory KLM for 40 years, and has tremendous experience in Orthotic management control whether prescription or over-the-counter type of orthotics and foot and ankle orthosis. So, I think it’s an important element that we should be very much aware of, it gives us that much better results post-operatively, and it falls right into what I was talking about this morning, in what our responsibilities are with patients in the post-operative stage.

    So, please welcome, Scott Marshall.

    Scott Marshall: Thank you, Harold. So, today there’s well over a hundred different orthotic labs out there that can service your foot orthotic needs. And really from any of us you can order an orthotic via specific condition such as hallux abducto valgus, planar fasciitis, functional hallux limitus, or you can order via specific application like running, aerobics, golf, football, et cetera.

    What separates you, the podiatric medical specialists from everybody else out there ordering orthotics, is your ability to integrate surgical orthotic and pedorthic care as required, to maximize the patient’s specific benefit.

    In fact, your ability to take an orthotic labs standard designs and enhance them to fit the specific needs of a patient, is really innate to the specialty of podiatric medicine. It’s one of things that makes you the regional specialists of the foot and ankle.

    And so my goal today is to get you to understand the why behind the what when you’re customizing a lab standard prescriptions to meet the needs of a particular patient and I’m going to try and cover everything you see on this slide.

    I’m going to start with the materials we all use to make the orthotics shell with, and again we all used the same stuff composites, plastics, foams, and leather.

    Now, graphites and composites get their properties from the strands of graphites and fiberglass that are layered in the material. They’re typically the thinnest, lowest profiled devices that we make out there, graphite typically 1 to 2 millimeters, fiberglass typically 2 to 3 millimeters. And because they have the thinnest profile you get the best shoe fit from them but they also give you more options, more modifications that you can make in your prescriptions.

    The stiffness is determined by both the weave, and the size of the strands. And so for the same thickness of the material, you could have a rigid, or a semi-flexible, or a completely flexible device. That’s unlike all the other materials that we used.

    We also have the longest life span, and this is the ability of the material to flex, and then rebound towards the original thermal form corrected shape.

    They also are the on lightest in weight and actually probably the most superior material we have are the composites, but the problem is, they are definitely the most expensive by a long shot but they’re great materials.

    Now, plastics called polypropylene and subortholene these are the most popular materials that we used. It typically come in different thicknesses and colors which is a big reason for their popularity.

    And it’s the thickness of that shell that determines its particular stiffness. So on one patient, a 3 millimeter shell is going to be more flexible than a 4, and that will be more flexible than a 5. And It’s the same with its lifespan, the thinner the material, the faster it’s going to bottom out for you, the thicker, the more rigid, the longer it’s going to maintain its shape.

    They represent the median as far as orthotic weight, and they are the least expensive material we use which is another reason why they’re so popular.

    Now, for your patients you can’t tolerate plastics, you typically want to go towards EVA, foams and leathers. These materials like plastics come in many different thicknesses and many different colors and also durometers.

    Quite often used for your diabetic geriatric patients who need a more accommodative orthotic or just your patients who need a more forgiving shell, or they need a softer interface against the skin, i.e., your neopathic patients.

    Their stiffness is determined by both the thickness and the durometer in how their combined. So, a very thin material of low duromoters is going to be very soft and cushiony, a thick material high durometer is going to be very dense and very stiff. And so how you combined those will give you stiffness of the device so you can make them very soft and flexible or you can make them very rigid, depending on how you mix the materials together, how you combine them.

    They’re definitely the heaviest and the bulkiest devices that we make for the orthotic shell, often require extra depth shoes, and they certainly have the shortest lifespan, and definitely the median as far as cost.

    So, now that we’ve kind of talked about the core, the shell of the orthotic, now I want to go through some of the areas where you can modify that orthotic, to better enhance the performance for the patient. And I’m going to start with heel area.

    And the first thing I want you to think about is the heel cup height. Most labs choose gender and shoe type to determine that heel cup on their generic devices.

    Typically a man’s a 12 millimeter heel cup, women is about 10 millimeter heel cup. And the reason for this is the higher the heel cup, the more you’re lifting the foot in the shoe and also the wider the device, and women shoes are typically tighter fitting. So, typically we will air on the lower heel cup for a woman’s orthotic.

    Now, in contrast to this, a sport orthotic is usually 16 millimeters and the reason for this, most sport shoes have removable insoles, and so with a removable insole, you have a lot more options you can do in your orthotic.

    Now, what I want you to realize today is that we all measure heel cup height differently. Some labs measure it on the inside and some measure it on the outside. So, if you look at the bottom corner here, you’ve got a 12 millimeter inside heel cup and a 16 millimeter outside heel cup.

    And the reason for that is the shell is 4 millimeters thick, and so if you’re trying to order a 16 millimeter inside heel cup to really control pronation, and your lab is measuring it on the outside, you’re not going to get the level of pronation that – control that you’re interest in.

    Now, one option that you have here is, you can always have your lab plant or dry in the heel of polypropylene and subortholene shells toward there about a millimeter thick and this will keep the inside and the outside relatively the same height, but you cannot plant on dry in composites because if you do, you grind into the strands and into the weave, and you’re going to compromise the integrity of the shell, in fact it will break right where you compromise the integrity of it.

    A little pearl for you [? 07:24], the higher the heel cup, the more controlling device that you have. So you could tell from the upper picture, the higher up you go on the foot, the more surface area you contact, the more you control it. It’s also going to stiffen the device because you’re going to have more curvature where there heel cup transitions into the medial and the lateral arches.

    There’s also times when you want to increase the medial heel cup, especially to resist heel contact pronation. Likewise if you have a patient with lateral instability or tends to laterally sprain, you want increase that lateral heel cup height.

    Rearfoot posts are added to slow or control pronation from heel contact, and into early mid-stance phase of gait. Also, excellent for a low subtalar joint axis or whenever you have significant subtalar joint motion in the frontal plane. Usually, made from hard rubber or a high durometer EVA, and many orthotics come standard with sport orthotics, so mostly your sport type devices will typically come standard with a rearfoot post.

    The standard is typically 4 degrees of inversion with no motion, and basically the resistance pronation is done by the softness or the hardness of the material. So, a low durometer rearfoot post is going to resist pronation less than a high durometer rearfoot post.

    But you can add more or less depending on the patient need for example if you have a marathoner or someone that runs a lot of miles, a heavy pronator, you may want to go to a 6 degree inverted rearfoot post.

    You just want to remember that the more you invert that rearfoot post, the more material you’re putting under the heel, which means you’re going to lift that orthotic up in the shoe.

    Likewise, if you have a lateral ankle sprain or someone with lateral instability you’d want to go with a zero degree, a flat rearfoot post to really resist at supination at heel contact.

    You can also actually grind in the exact amount of motion in a post rather than depend on the compressibility of the material, like four degrees of inversion, four degrees of motion, and this certainly will help keep the orthotic thinner in the heel. But no matter how you slice it, adding a rear foot post is going to lift that heel up a little bit in the shoe, and you’re gonna hear me say over and over again how shoe fit is a critical decision point and how you modify your prescriptions.

    You can add flares to post, these are great modifications, and may increase the area of control. So typically, a rear foot post is in-flared for shoe fit reasons.

    [10:00]

    So you can see in the bottom picture how much more control area we have on the plantar aspect to that pose.

    Media flares really help delay both the extent and the speed of heel contact pronation and also excellent for stabilizing the subtalar joint. Likewise, lateral flares are excellent for lateral instability, your lateral ankles sprainers, your cavus-type feet that maintain a supinated position throughout the gait. And again, we’re putting a lot more material in the shoe so you’ve got to be careful on how you put a flare into a patient’s shoe.

    Now, you could have Heel Lifts in the orthotic, to any rear foot post as well, typically used to accommodate a limb length discrepancy, but also excellent for your equinus patients, especially if they have osseousis equinus or a forefoot equinus.

    Normal shoes, you could usually put about 6 mm of lift in the shoe. But if you have a shoe that has replaceable insole or an extra depth [? 11:01] shoe, you can get a lot more lift in the shoe as well. And it’s good to note that that’s the best way to deal with the limb length discrepancy is to raise the entire plain of the foot simultaneously.

    Medial Skives are another really important modification. They also create an additional resistance to pronation during heel contact in early mid-stance similar to a rear foot post. In fact, there’s quite a few studies that show that medial skives are effective, if not, more effective than a rear foot post. And the way that we do this is we flatten the medial area on the plaster model or the positive model under the medial aspect of the calcaneus. And that flat spot will, right there, go into the heel cup, so instead of having a nice parabola, you can see where that flat spot is going to push up on the medial aspect of the calcaneus giving you a supinatory moment or a resistance to pronation. You typically order this in the amount of millimeters that you want shave your flattened up, 2 mm, 4, 6 being the most resistant.

    Excellent to do this in combination with other modifications, so you’re rapid pronators really benefit by combining not only a medial skive but a deep medial heel cup at the medial flare on the post as well.

    Lateral skive, same concept, we’re going to flatten an area laterally on the positive to give ourselves a flat area, to push up on the lateral aspects of the calcaneus, give us a pronatory moment at heel contact. And again, if patients with lateral instability, great combination, high lateral heel cup, lateral flare on the post and a lateral skive as well.

    You can also add heel padding to any orthotic, great if you have tender heels, but also great if you could put a horseshoe pad or a donut pad and offload the particular sore tender area, like for planar fasciitis or for heels spurs. But 3 mm, 4 mm max is what you can get out of a normal shoe. Again, if you’ve got a shoe with a removable insole or you have a shoe, an extra depth shoe, you can get a lot more padding in there.

    Now, let’s look at the medial arch. So the role of the medial arch correction is to actually flare the medial edge of the orthotic away from the natural contour of the foot to allow some flattening of the medial arch. But you can do more or less depending on the patient need. For example, you can do more, you can put more material in there. And what that’s going to do is lower the medial arch on the final orthotic shell which is going to allow the foot to pronate more on that device.

    Now, this is an excellent option for your elderly patients or maybe your more obese patients where you don’t think they can handle full control. Likewise, you can add less fill which will mean you’re going to have a higher medial arch of the device, a more controlling device. Here’s an excellent option for your more competitive athletes or your young adults and kids who can really tolerate the additional control.

    A little pearl for you, by adding less medial arch fill and a high heel cup, you’re going to get a stiffer orthotic shell so you can possibly use a thinner plastic plate or a more flexible composite weave. Likewise, by ordering more medial arch fill and a lower heel cup, you’re going to get a less stiff, more flexible orthotic, more forgiving orthotic if your patients can’t handle full control.

    Plantar arch fills are very popular in sports applications where you want flexibility in the shell but you don’t want it to bottom out, and the key here is the durometer of the plantar fill material. So, if I have someone who’s doing a lot of stop/start sport, like tennis, I would go with a higher durometer material and want something a little stiffer, a high durometer EVA, say, 65 durometer, whereas if I’m making an orthotic for someone doing aerobics, I’m going to want more flexibility in that arch area.

    [15:00]

    So, I would go with a low durometer material like Poron. The thing you want to remember, again, if you’re filling the shoe, and so you all want to use plantar arch fills for shoes that have removable insoles.

    Medial flanges are added to increase the stiffness and the pronation control of the orthotic. We do this by rounding up the medial side of the arch correction. And what this does, so we still allow that medial part of the orthotic to flare away from the foot and then it’s going to wrap up under the talar or navicular area, like through here, really stiffens the device and gives you much more control. The problem is that a lot of adults can’t tolerate the additional correction and a lot of adult shoes don’t accommodate the medial flanges very well. But, wow, fantastic for pediatric patients and kids, they tolerate it, no problem, the shoes typically handle it. And, in fact, it’s an integral part of your typically UCBL type device.

    Fascial Band Accommodations are added for patients who have a flexible anterior cavus which causes the plantar fascia to bowstring at heel off. You can really easily see this by just dorsiflexing the hallux and looking at the plantar surface of the foot between the first and second met, and you’ll see that bowstringing of the plantar fascia and the Hallucis Longus. And what you want to do is you want to mark that, you want to make sure that it’s visible in your foam and pressure, in your plaster casts, your digital scan, and the lab will actually put a ridge of material that will create a little concave groove for that bowstringing to fit into without compromising the ability to control the foot.

    The lateral arch, so the role of the lateral arch is to accommodate or… correction here, it’s to accommodate fat pad expansion during weight bearing around the heel and, of course, up the lateral border. And especially useful on your non-weight bearing casts, if you have a weight bearing cast, maybe you wouldn’t want to do it all. But it’s really important for you to really look at your patient and examine and see if they have excessive fat tissue or a lack of tissue in this area. If they’ve got an excessive amount of tissue, then you’re going to want to ask the lab for more. And if they have a lack of it, you’re going to want to ask them for less.

    And you have to remember that we, as the lab, never see any of these. We never examine the patient. So we take what we have and we do what we normally do. And the more you communicate with your lab, the more you understand their processes, the better result you’re going to get the first time around.

    Now, some patients have a very prone styloid process at the base of that fifth met, and sometimes this can cause irritation in the orthotic. So you can accommodate this. And what the lab will do is they’re going to add more material, both plantarly and laterally, to that styloid process area. This is going to create a nice little pocket for it to fit into comfortably and a lot of practitioners will also add a little foam in there to make it more comfortable. But if you have patients who want to subluxate like say the lateral foam at heel-off, that styloid process accommodation is an excellent modification to allow it to sunbluxate into but still control the foot with the rest of the orthotic.

    Lateral Flanges are added to prevent the foot from sliding laterally off your orthotic device. Same thing, we’re going to round that area more so that the orthotics are going to bend laterally up around the cuboid and up laterally around the heel. It definitely gives you a much stiffer device but also excellent for patients with the increased transverse compensating metatarsal joints, or whenever you want increased medial lateral control during mid-stance.

    Again, like your Medial Flange, quite often not tolerated by adults. It doesn’t quite fit in the shoes well, but a great options for your pediatric patients. In fact, with the Medial Lateral Flange, you can really control them well. And again this is an integral part of your typical UCBL type device.

    Now, all labs typically include a little transverse arch supports in the shell of the orthotic itself, two the three millimeters maybe. But a lot of practitioners like to add more to not only lift the second through fourth with the apex under the third but to cushion on the met heads, say for example if we have a lack of fat tissue for cushioning. But it’s also an excellent way to engage the windlass mechanism. Now, all the labs typically have –

    [20:00]

    – different size metatarsal pads – small, medium, large, extra-large.

    So, when you order, you just have to tell the lab which size you want and then tell it how high you want it and whether you wanted a soft or firm materials. So you can mix and match them any way you want. You can make a large pad that’s very low out of a firm material or a small pad that’s very high out of a very soft material.

    Met Bars, do the same thing but they lift and cushion all the met heads simultaneously. Also excellent for engaging the windlass mechanism and basically tell the lab how high you want it and whether you want it soft or firm.

    Neuroma Pads, you want to add those when you want to lift and separate two metatarsal heads and prevent them from pinching, say a tender nerve or some other tissue, for example scar tissue. Same, you just need to tell the lab which interspace you got to put it into and then how high you want it and whether you want it firm or extremely soft.

    The thing you want to remember about Met Pads, Met Bars and Neuroma Pads is you’re erasing the metatarsals up in the toe box of the shoe so you can create shoe fit problems. So again, the shoe is a critical component of your decision-making process.

    Now probably the most popular modification that gets made to every orthotic out there is a forefoot accommodation to offload a tender area like IPKs, lesions, calluses et cetera. And what the lab is going to do is they’re going to add an extension to the distal edge of that orthotic and then they’re going to put another pad on top of it to accommodate or offload the area that you want to accommodate.

    In addition, lots of practitioners typically combine it with a Met Pad so that you’re going raise that area proximal to the metatarsal as well, further relieving pressure on that particular sore tender spot. The main thing you want to think about is marking it in your cut cast or foam, your digital scan. Make sure the lab knows exactly where they want it put and how big it needs to be.

    Morton’s Extensions, these are indicated for your patients that have a structural elevatus of the 1st ray. That is when that 2nd met head is bearing weight excessively and the 1st cannot plantarflex in late mid-stance and propulsion. Basically, we’re going to preload that first metatarsal area and we’re going to balance that load with the second. Very useful for hallux limitus and hallux rigidus or really whenever motion at the first metatarsal phalangeal joint is not desired. Again, what you’re doing is you’re going to support that met and hallux in late mid-stance and propulsion in relation to 2 through 5.

    Exactly opposite is your Dancer’s Pad or what we call – some call Kinetic Wedge. Here, similar to a first met offload accommodation, but basically we’re going to cut out an area on the first and we’re going to raise 2 through 5. So this is going to allowed the first met head to drop and function below 2 through 5.

    Excellent Functional Hallux Limitus where that plantar repositioning of the first ray down enables first metatarsal phalangeal joint dorsiflexion. Do a lot of this kind of stuff too.

    Varus and Valgus Sulcus Wedges, so what these do is these carry our correction from the distal edge of the orthotic forward under the ball of the foot and even to the end of the toes. And basically, when you balance the forefoot to the rearfoot, let’s say you have a patient with ten degrees of forefoot varus, when you balance that out, that correction ends at the medial distal tip of the orthotic. And so if the rearfoot control created by the orthotic does not give you medial column plantarflexing during propulsion, Varus Sulcus Wedge is an excellent option. And basically, what we’re going to do is we’re going to be paper thin under the fifth met up to maybe six millimeters under the first met, so you’ve got an inverted wedge that’s giving you a supinatory moment from heel off all the way through propulsion. Also excellent for your runners if they’re pronating rapidly. Once the heel comes off, you can put this in there and it will help control that pronation all the way through the gait cycle.

    Likewise, Valgus Sulcus Wedge, paper thin under the first met up to about six millimeters under the fifth met, really good for your supinators, for your lateral instability, and also an excellent way to stabilize a medial column in late stance and into propulsion. Then you want to remember you’re filling up the toe box of the shoe, so not recommended for shoes that do not have a removable insole.

    Toe Crests are added when you want to fill that sulcus groove. Excellent for stabilizing rigid and semi-rigid hammertoes.

    [25:00]

    Again, you can order this from soft or firm materials depending on whether you want a little give in there or whether you’re really trying to support those hammertoes. And always typically combined with these other modifications to stabilize the foot from heel contact through mid-stance and into propulsion.

    And on a final note, the width of your orthoses is a primary concern. Now the goal of our orthotics is to really contour as much of the foot as possible but still be comfortable and still fit in the shoe, right? And so, the labs typically want to air on less contour and narrow devices. Why? Because we don’t want to get them back. If they’re too wide, we don’t want to get them back. You know, if it’s less contouring, it’s probably going to be more acceptable to the patient. Whereas the practitioner typically wants to air on wider orthotics and more contouring orthotics to get more control of the patient.

    So your pearl here, always specify your shoe type. It’s really important for the technician to know what this is going into, especially if you want their opinion on how to make the orthotic for this particular patient. Or if we see that you’re going to put this in a man’s loafer or a woman’s fashion shoe and you’re adding medial flares or lateral flares, we’re going to call you say, “Probably not a good idea,” rather than send it to you and have you returned it anyway and you don’t look too good in front of the patient.

    For women’s fashion shoes, if you can send a representative sample, excellent, excellent thing to do. Because this way the technician doesn’t have to guess on shank curvature, heel counter limitations or toe box limitations.

    Now, there are some times when you want them wide or narrow. As an example of cavus feet with metatarsal, you want that orthotic as wide as possible. Or if you’re trying to get that first to function below 2 through 5, narrow that orthotic medially, ask for a narrow device and possibly even grind back that medial distal tip at a slant so that you allow that first and the medical column to drop and function as low as possible compared to 2 through 5.

    And always advice your patients to buy shoes with removable insoles. Today, most shoes are coming with removable insoles, which is great for you because this gives you so many more options in what you can do for that patient.

    So in summary, your goal is to improve foot function and ankle function and alleviate pain. Surgery, orthoses and shoes therapy are the tools you need to achieve that goal. Clinical Biomechanics is the core knowledge you need to use these tools. And of course, the best practitioners integrate all three. And this is how you become the regional specialist of the foot and ankle, the go-to person for foot and ankle treatment in your area. Thank you.


    TAPE ENDS - [0:28:08]