Shells 101

Brittany Meyer, Manager

Brittany Meyer, Manager

 Have you ever wondered how an orthotic gets its shape?

In this blog you will learn Allied OSI Labs standards on how we give an orthotic its shape.

First to determine length, bisect the 1st and 5th metatarsal heads. Lower the 1st met head 12mm and the 5th met head 10mm. That would make the distal edge of the shell to stop on the patient just before their metatarsal heads. It will still give you the control that is required for the patient.

3 grind width options:

-Wide Grind: Bisect the 1st met and move the bisection 1/8” medially

-Regular Grind: The bisection of the 1st

-Narrow Grind: Bisect the 1st met and move the bisection 1/8” laterally. The shell is ground into a “peanut” shape. (This will affect the arch height)

4 arch height options:

-No Arch Fill: The casts will be done to the exact height of the patient’s foot

-High Arch: The cast will have 0.13” (1/8”) added to the arch area.

-Medium Arch (standard): The casts will have 0.25” (1/4”) added to the arch area.

-Low Arch: The casts will have 0.50” (1/2”) added in the arch area.

All of Allied OSI Labs “Dress” products come with a narrow grind. We highly recommend that you always order a no arch fill on a dress product or any narrow grind device. Since Allied OSI Labs grinds the shell into a “peanut” shape, we are grinding into the arch area and it will lower the arch on the medial side. The orthotic will conform to the shape of the arch on the foot since the arch gets lower as it transitions into the middle of the foot.

If you have any questions or concerns, please contact us at [email protected] or 800.444.3632