One of the more common issues that patients might complain of when first wearing a new orthosis is that one or both orthoses may feel like they are “too far forward” in the shoe. The patient may even complain that he or she feels like the orthotic does not match his or her foot well. However, when you compare the orthosis to the foot, you will likely find that, as long as you took a good negative cast and use a lab with high standards for castwork, the orthosis matches the foot very well.
The first thing you must do is to ensure that the orthosis is really not sitting too far forward in the shoe. The most common reason for this is that the shoe is too narrow for the heel cup so the orthosis is not allowed to slide all the way back into the shoe. If the orthosis appears to fit well in the shoe, then follow the instructions below.
The most common reason for a patient to feel as if an orthosis is sitting too far forward in their shoe is simply the device applying more force on the anterior aspect of the foot than on the posterior aspect. This can occur for a number of reasons; one being that one foot pronates a bit more than the other thereby increasing force between the foot and orthosis on that side.
Podiatrists can address this issue very easily. Simply grind the bottom aspect of the polypropylene orthosis in the anterior medial arch. This will thin the orthosis distally, making it more flexible and decreasing the force the orthosis is applying to the foot. By decreasing the force applied anteriorly, you will increase relative force being applied more posteriorly. This will usually eliminate the sensation of the orthosis sitting too far forward in the shoe
You can see a video demonstrating this adjustment here: http://prolaborthotics.com/Blog/tabid/90/EntryID/175/Default.aspx  .
This issue brings to light a couple other important points for the podiatrist wishing to provide optimum orthotic therapy for patients. First, the ability to make easy adjustments like this one is one of the reasons I feel polypropylene is currently the best material for manufacturing custom foot orthoses. Second, the best orthotic practitioners will have a grinder in their clinics, allowing them to make the more commonly needed orthotic adjustments during the patient’s appointment.
Editor’s note: This blog was originally published at www.prolaborthotics.com/Blog/tabid/90/EntryID/425/Default.aspx  and has been adapted with permission from Lawrence Huppin, DPM, and ProLab Orthotics. For more information, visit www.prolaborthotics.com  .