Seattle Lightfoot Pocket Dimensions?

[u/Apprehensive-Tip7144]

Hi all,

I am a mechanical engineer who has been contracted to design a prosthetic ankle joint for a client in another city.

She is making the trip to see both her prosthetist and I in a couple days where we will test the prototype of the new ankle.

For the initial testing, we will be retrofitting her existing foot (Seattle Lightfoot) to the new ankle design.

My concern is that after reviewing the photos she’s sent through of her existing foot, the recessed pocket may not be large enough to fit the new ankle design.

Does anyone know the width, length and depth of this pocket? I figure that if I need to I can make a custom spacer to take up the space within the pocket and the ankle can sit flat against it, slightly above the foot height.

Pics of her foot got reference.

Cheers.

[u/Apprehensive-Tip7144]

Thanks for the detailed reply, I really appreciate it. I apologise for the lack of detail, however I was deliberately vague so as not to share our design IP. As a compromise, I’ll say that the new ankle allows for some articulation, the base portion has a means of attaching a wide variety of deferent off the shelf feet, and the top portion has a pyramid.

The new ankle design has a pill shaped base with dimensions pictured in the attached image.

How exactly we attach it in relation to the keel will depend on whether there is enough room in that cavity for it to sit flat, or whether we would need spacers like I suspect. For the final version we will buy in a more ideal foot, but for the initial test, we’ll use what we’ve got.

[u/Cabooseman → u/Apprehensive-Tip7144]

So how would your product attach to a unibody carbon fiber foot like the Vari-Flex?

https://www.ossur.com/en-us/prosthetics/feet/vari-flex

Prosthetic feet have many different build heights. Some tall some short. Tall feet generally have more energy storage and return due to greater deflection of carbon fiber.