Hi everyone craig payne here i just want to talk to you about a little trick that i’ve developed with these things. These are the Archie’s thongs. Now we call these thongs in Australia, jandals in new zealand and flip-flops in the rest of the world, but these come with an arch support built into them and we sell them like hot cakes in the clinic pretty much everyone who tries them on likes them. The problem is with any arch support or any or even in these or in the orthotic. If that arch support pushes right where the subtalar joint axis happens to be that they can actually be uncomfortable or even worse, if the subtotal joint axis is very medial, the actual arch support area is on the lateral side of that joint axis and there’s actually a Pronatory moment at the subtalar joint, so that’s not exactly a desirable thing.
So what i want to show you? What i do is what i’ve done with some of these now this is my daughter steffy who who’s volunteered to be a participant in this little demonstration. Now i’ve made no secret of my of being a bit of a fan of the MOSI, the medial obliques of subtalar inclination, um, foot, orthotic or design feature in foot orthotics and combined with that. The importance of the subtalar joint axis and prescribing foot orthotics because, as you’ll see in this foot here it’s actually quite the access is quite medial. So what i want to try and do is incorporate a MOSI design feature into these Archies to try and um one make them more comfortable and probably perhaps more effective.
So the first thing i’m going to do is work out where the subpaler joint axis again. This is not a lesson on how to find the subtitle to a nexus, there’s plenty of information available elsewhere on that. This is also not a lecture on the MOSI design feature um, there’s plenty of information on that elsewhere. I have a whole lesson in my online clinical biomechanics boot camp sort of on this mozzie design feature. But if i was to try and palpate steffi’s subtotal joint axis, it’s here um, you know you can see that.
So this is the area where we want the design to work and if you even just look at the, even though i promise this isn’t a lesson on mozzies, you can see this whole area here of the arch is on the lateral side of the axis. So i’m going to mark this quite sort of with this felt, pin there’s a little ticklish and we’re going to put there put the arches on the foot and then what i’ve done. You can see i’ve just transferred that sub taylor joint axis of hers onto the device. So let me just stop the video here i’ll go and do something and then come back and then show you what i’ve done. Okay, so you can see what i’ve done here.
The first thing i’ve done is just i’ve used. I’Ve used a gray, eva and i’ve. It’S a about five six mil thick and i’ve glued it on on the medial side of that line. Now don’t forget that line that i drew is going to be different in everyone’s foot. It’S going to be in a different place, so you you’d move it around now i did have to heat up the eva to get it to fit into the curvature.
So what i’m going to do now and i’ll go ahead, and do this and come back is just better shape it and finish it so that we’ve got more load on the medial side of the subtalar joint axis now, combined with a bit of arch support that Come in these arches combined together are going to give a much more comfortable and a much better control of stiffy’s foot. Okay, so you can see what i’ve done here now. I’Ve done it in grey um, because i want you to be able to see it now. If i was doing this for a patient, i’d use, a white, eva arches come in a whole range of different colors, so we have a lot of different eva that will we’ll shape. So you can see how you know: i’ve ground that edge, smooth we’ve smoothed off that edge so stiffy wearing this.
We just put it on um. You can’t actually see from behind, but you can see what’s happening. Is we’ve got an extra force or or low on the medial side of that subtable joint axis? So can we just look so hopefully you find that as a useful design, design feature that you can add on to products like these that actually helps those ones that are not comfortable, because the arch area pushes right on the joint axis, and i think we just Know from experience with foot orthoses that, if there’s just too much force right where that subcover joint axis is it’s just uncomfortable um or as in steffy’s case. The arch here is actually on the lateral side of the sub-television axis.