# A Prototype for an Inexpensive Foot Abduction Brace Using 3D Printing --- For more pictures from this project, [check out the gallery](https://hub.e-nable.org/u/kreeser1/gallery/custom-gallery/view?openGalleryId=87#.jpeg). --- ### Clubfoot On my first day at [Lake Victoria Disability Centre](https://hub.e-nable.org/u/kreeser1/wiki/page/view?title=Lake+Victoria+Disability+Centre+-+Complete+Article "Lake Victoria Disability Centre - Complete Article") (LVDC) in Musoma, Tanzania, I was told that northern Tanzania has a strikingly high number of [clubfoot](https://en.wikipedia.org/wiki/Clubfoot) cases. Clubfoot is a birth defect affecting the bones and muscles in the feet, causing the foot to be twisted inward into an unnatural position. While not generally painful for the child, the condition needs to be corrected through orthotics as soon as possible after birth, or the child will grow to be permanently disfigured and potentially unable to walk.  ###### A diagram showing the physical differences between a normal foot and a clubfoot. ###### Source: [https://kidshealth.org/en/parents/clubfoot.html](https://kidshealth.org/en/parents/clubfoot.html) --- Rajab Hamis, director of the Prosthetics and Orthotics department at LVDC has personally treated more than 150 such cases. Rajab’s treatment for clubfoot in babies and small children generally involves a series of plaster casts over several weeks or months to slowly move the feet into a more natural position.  ###### Repositioning clubfoot with a series of plaster casts. ###### Source: [https://www.mdorthopaedics.com/ponseti-afo-solutions/](https://www.mdorthopaedics.com/ponseti-afo-solutions/) --- Once repositioned, an ankle-foot orthotic (AFO) brace is fit onto the corrected foot to maintain the right position as the baby grows. Otherwise, the foot can often revert back to its previously twisted position. For the first several months, a brace is kept on the feet constantly. For several years after that, a brace is generally only worn while sleeping. As you can imagine, replacing these orthotic devices regularly as the child grows is necessary, but expensive. The foot abduction brace is often used in addition to, or in place of, the AFO while treating cases of clubfoot. The foot abduction brace is a set of two boots connected through a metal bar.  ###### Source: [https://www.aboutkidshealth.ca/article?contentid=1192&language=english](https://www.aboutkidshealth.ca/article?contentid=1192&language=english) --- The angle that the boots make relative to each other is adjustable, as is the distance between the boots. The foot abduction braces that I was introduced to come in a series of increasing boot sizes (approximately $215.00 USD/pair), while all could be used with the same connecting bar hardware (approximately $60.00 USD). Foot abduction braces are expensive and often donated to the facility, but due to the high number of clubfoot cases that Rajab treats, he regularly runs out. I immediately saw the potential for 3D printing to contribute to this area of need, and a prototype will be outlined in this article.  ###### Off-the-shelf boot and bar food abduction brace, [which retails for $275.00](https://mdorthopaedics.easyordershop.com/easyorder/index). --- Each boot was made of a sturdy plastic bottom, a thick rubber insert which makes contact with the foot, and a felt exterior with straps that hold the foot in place. The boots are connected to each other through a metal bar which can be lengthened or shortened to hold the feet an appropriate distance apart. The boots are angled relative to the bar in two dimensions: a fixed rotation due to a bend in the bar (see figure below), and a variable angle at the connection between the boot heel and the bar.  ###### Back view of an off-the-shelf boot and bar foot abduction brace. Note the bend in the bar as it meets the boot. --- ### Creating a Low-Cost Boot We began the project by taking apart an existing off-the-shelf boot, including each rivet holding the felt pieces of the boot together. The boot consisted of 8 separate felt pieces (2 large pieces making up the majority of the exterior, plus 3 straps and three buckles). We could have very easily traced these pieces and cut out our own, but the P&O department at LVDC needed to conserve resources, so we used these original felt pieces in our prototype. We hand-riveted the pieces back together, and replaced one of the original buckles with a different type of buckle as proof-of-concept that our prototype could use different parts. We used contact adhesive to glue the bottom of the main felt piece to a piece of cardboard cut roughly into the shape of the bottom of a shoe. This was not crucial but was done for stability and later positioning. Next, a set of boot bottoms were 3D printed in brown PLA. Rajab explained that is was crucial to have a tall rim around the boot base so that the child’s toes do not come up and over the lip of the rim, causing the foot to sit in a weird position in the boot.  The bottom of the card board (to which the felt pieces were attached) was then glued to the top of the 3D printed boot bottom using contact adhesive. ### Making and Installing a Thermoformed Foam Insert As the only part of the boot that makes contact with the child’s foot, the boot insert should be comfortable. A plaster cast of a small foot was used as a form to thermoform a piece of polyethylene foam around.  The thermoformed polyethylene foam was then trimmed to create the insert, which includes a back portion, a bottom portion, and wings on the sides which slight fold over onto the top of the foot when the felt straps are cinched.  Contact adhesive was used to secure the foam insert into place, completing the low-cost foot abduction brace boot.  ### 3D Printed Bar      ### Takeaways The main felt pieces for the right and left boot are mirror images, so only one template is necessary to create these pieces for both boots. ### e-NABLE Community Call to Action