Foot Orthoses For Chronic Ankle Instability
In light of an increasing body of research on the
Are You Over-Prescribing Them?
Dr. Lloyd Nesbitt, DPM
How are your results going with the orthotics that you prescribe?
Do you find that too many patients complain about one thing or another with their orthotics? Or, that you wind up sending them back to the lab for adjustments or remakes?
While minor modifications with orthotics are sometimes inevitable, ongoing issues with adjustments, modifications or complete remakes can be avoided. Once in awhile the simple use of a sani grinder to reduce a forefoot varus or valgus post can be done in a minute while the patients waits- an easy fix. But when it comes to accommodations on full length orthotics, there is a risk for more issues.
Sometimes the thickened edge of an accommodation bothers a patient. Either because it is not in the exact right place, or because the drop off is too steep. A patient may complain that the material is too thick, or that they feel an uncomfortable tightness. Then it’s back to the fabrication lab, and an unhappy patient.
It is not unusual when it comes to accommodations on orthotics that some patients feel that they are not placed in the right spot, or they feel the edge is bothersome. Some patients can seem sensitive to everything, and the accommodations themselves can be a source of irritation to them.
Using extensions with accommodations is required much less often that most practitioners think. You can save yourself the aggravation by being less dependent on the use of accommodations in your prescriptions, and feel confident that the actual orthotic component (heel to met heads) is doing the job of correcting the biomechanics accurately, from heel strike to toe-off. A prescribed and casted orthotic should, in many cases, properly address the abnormal deforming forces so that the forefoot symptomology is reduced, without ever having to use forefoot accommodations. That would be a win-win for the patient and the practitioner.
Your measurements, casting technique, diagnostic acumen and your orthotic prescription all play a role in the end product. Many practitioners prefer to use full length orthotics as a general rule, which can be a double edged sword. Some patients prefer a full length orthotic. For example, runners putting in long distances prefer the cushioning and stability of a full length device. It should be noted that even semi-rigid, basic shell length orthotics should be comfortable when worn on top of the existing shoe insoles for someone running long distances.
There may be a tendency among practitioners to over-prescribe their orthotics, as in over-complicating them. Adding unnecessary accommodations can often be problematic for the patient and a source of frustration to the practitioner as well.
After many years of prescribing and dispensing orthotics, I have found that they simplest, thinnest (but still accurate) orthotics work best and most patients prefer that. I only use accommodations when the biomechanics can’t be corrected without them.
Here are some areas where orthotic accommodations are commonly used, but are not required:
1. Calluses inferior to their second and third metatarsal heads.
Perhaps upon first impression, a full length orthotic with an accommodation on the extension seems like the solution. Not necessarily so!
With pronation, there is valgus rotation of the metatarsal heads and shearing forces result in the callus formation. A full length orthotic with accommodation is commonly prescribed for this issue. The problem is that patients often won’t wear the orthotics in a lot of their footwear because of the bulk. Or the accommodated area can be bothersome. However, if a thinner orthotic without extensions (i.e. only shell length) were used, then the patient would be more compliant in being able to easily wear them in a lot more of their footwear. A better result overall.
Orthotics without accommodations or even without full length extensions would still control the abnormal biomechanics and eliminate the pronatory forces so that the callus formation and shearing should not recur, or at least be drastically reduced. You can still achieve the desired end result without accommodations, and patients can more easily move their devices from one pair of shoes to another.
2. In the case of a rigid pes cavus foot type, there may be a natural tenancy to want to accommodate the metatarsal head area, particularly the first and fifth metatarsal heads that bear more than their fair share of weight.
Once again, the same principle applies with thinner, shorter orthotics without extensions. In this case, exhibiting the opposite of pronatory forces, the rigid pes cavus foot type has excessive pressure at the heel, and first and fifth metatarsal heads.
It has been my experience over many years with the use of thinner, shorter devices that patients are more willing to wear orthotics more of the time. The results are excellent in that the orthotics accurately match the shape of the foot in a rigid cavus foot type, and so they will offload weight-bearing to the metatarsal heads. Concomitant forefoot valgus posting may be required, but you would be surprised as to how effective the orthotics can be without any accommodations or extensions.
In my practice, only about 5% of orthotic devices would have full length extensions requiring accommodations.
3. While it is not unusual for me to prescribe a full length orthotic, because the patient wants to use them exclusively in their running shoes or hiking boots, I will usually avoid accommodations unless it is absolutely necessary.
In theory, it would be understandable that accommodations could be used for every sore spot on the ball of the foot. In practice though, that is not necessary at all, since the orthotic itself does the work in addressing the causative factors that created the symptomatic areas at the metatarsal head level.
I’ve you’ve been having trouble with the accommodations on your orthotic extensions it may be time to revaluate your prescribing. If your orthotics are accurate in the first place as shell length devices with no extensions, you may find that your patients will appreciate a less bulky, more versatile device. This seems to be a case where less is more. Less bulk and more compliance. Less returns to the lab and more optimal results the first time around.
If you are taking an accurate cast of the foot and have a proper biomechanical prescription, then try making orthotics without extensions and accommodations. If you really prefer to use full length orthotics, that’s fine. You may be pleasantly surprised to see that without accommodations on the extensions, your patients will still enjoy wearing their orthotics and experience good results. Scrapping the requirement for accommodations on your orthotics may make your life easier and your patients less frustrated with repeat visits and your continued attempts at making the orthotics more comfortable. Avoiding the back-and-forth changes and modifications at the lab will save you and your patients a lot of time and aggravation.
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