Designing Orthotics for Young Patients with Cerebral Palsy
By Victoria Z. Lubas
Inside the MakerSpace at Tandon’s MetroTech Center, Victoria Bill, MakerSpace Manager, and Gabriella Cammarata, recent graduate of the Integrated Digital Media master’s program, are leading a Vertically Integrated Project (VIP) class in which students 3D print braces for children living with cerebral palsy. According to the Centers for Disease Control, “cerebral palsy (CP) is the most common motor disability in childhood…[affecting] from 1.5 to more than 4 per 1,000 live births or children of a defined age range.”1
The project began in 2016, when faculty from NYU Langone Health, the Rusk Rehabilitation team, and the NYU Ability Project approached the MakerSpace for their expertise on 3D printing. Teaming up with occupational therapists and working with patients selected by Rusk, members of Tandon’s VIP class, 3D Printed Biomedical Devices, get to combine patient interaction with technological advancement to directly help a child with CP.
Making the Brace
The first step to making a brace is scanning the patient’s arm using Heges, an iPhone app which records accurate 3D measurements. This app means they no longer base their designs on ruler measurements obtained from Rusk, which Victoria Bill appreciates since that system makes it “hard to have 3D printed parts.” Since the project began, improvements in apps have led to evolved scanning abilities, greatly increasing the ease of measurement-taking. Scanning also means they no longer have to manually design each piece, streamlining the process. Using the data obtained from the scan, the brace is built using the 3D design program, Rhino 3D.
Next, the brace is printed using an Ultimaker printer and wearer-friendly PLA plastic2 (similar to what is used to make plastic cups). The team prefers this plastic over harder ABS plastic (used to make objects such as LEGOs) because that hardness and the potential that patients’ skin could react to it makes it less wearer-friendly. Once the basic brace is complete, a series of fittings is scheduled between the patient and an occupational therapist to determine ways the brace could be further customized to provide the best results for each individual.
Currently, the project works with patients who have a hand stuck in flexion to create a brace that reaches from hand to elbow. The brace looks similar to a cast, is printed in two separate halves, and lined with neoprene, a fabric often used in wet suits. By printing the brace in separate parts, it is possible to reprint just the one part that needs corrections instead of having to print a whole new brace to make an adjustment. On the distal end of the brace there are three loops for the patient’s fingers that connect to the rest of the brace by fishing wire. This string system enables the hand to open when the elbow is moved a certain way.
Subsequent fittings with an occupational therapist provide the opportunity for intricate adjustments to the brace to directly address a specific patient’s needs, which often includes lengthening the brace’s elbow-to-finger wire. Gabriella Cammarata explained, “to make [the] fingers open correctly is [the] smallest, hardest, more important part of [a] brace.”
Overall, printing a brace takes about one day, with several printers working at the same time. The scanning and printing process is led by students, so the process from beginning to end can take one to two weeks, depending on the time of the semester.
Created in the Classroom
When this project first began, Cammarata worked with one or two undergraduate student workers. In January 2018, Cammarata was able to expand the project into a full course involving as many as fifteen students per semester. “Moving from a traditional research project to course marked an important change in the project,” said Cammarata. This transition has given many more students the opportunity to scan, print, and assemble braces and experience real patient interaction. This increase in man power resulted in a more rapid advancement of the brace. Cammarata continued, “one of the benefits of the class format is that we’ve really been able to perfect the approach. …[Now it’s] not just making something that works. [It’s] much more user friendly. More than ‘does it work?’ but ‘how [does it work]?’”
As a VIP class, students are able to earn one-to-three credits per semester for participating in this project and are encouraged to retake the course several times. Sequential enrollments in the course make for a more productive project with less time spent training a full class at the start of every academic term. As students reach their junior and senior years, they mentor the sophomores in the class.
The 3D Printed Biomedical Devices class meets once a week and consists solely of lab and printing time with no additional reading or homework. During these brainstorming design sessions, students solve shortcomings with the brace’s design and continue to improve it to create a more positive patient experience. During the project’s early days, the braces were printed as rounded, forearm-covering pieces that were difficult to print and to fit over a patient’s arm. The change to printing the brace in parts, connecting them, and lining them with fabric makes the braces much easier to print and wear, and much more comfortable. One brainstorming session also yielded a much smaller over-the-knuckle piece that holds the wires in a better position and uses less plastic, while also looking sleeker than the original model.
Looking Ahead
Since the program’s start in 2016, braces have been developed for six patients. The patients, usually aged six to 15, are selected by the Rusk Center for Rehabilitation because their type of disability is one that can currently be treated with the braces Tandon prints: hands that need help being opened. A future goal of this program is to develop a brace that can help opened hands close, allowing them to assist even more patients.
An ongoing goal of the MakerBrace program is to keep costs low. Heavy-duty medical braces, often priced at thousands of dollars, are typically not covered by insurance because children outgrow the braces too quickly to make it cost-effective.
The MakerSpace has been able to make their braces for less than $25, and those costs are covered by the medical and 3D printing budgets, meaning patients’ parents do not have to pay. Braces are important for children with CP because the arm mobility they give patients strengthens the muscles and can result in an improved condition over time. Bill explained, “Occupational therapists see this as a device for added functionality…and [as a] therapeutic device — as [you] move [your] arm and brace it also trains [the] muscle and brain…to give them added functionality,” such as the new ability to open and hold a water bottle.
The 3D Printed Biomedical Devices class is open to all students as an elective. While it is held in Tandon’s MakerSpace, it is not exclusively for Tandon students and offers an opportunity for students from various academic backgrounds to familiarize themselves with emerging tech and witness its ability to help others. Offering the course as repeatable and for credits allows students to work as a team to improve the project over the course of several semesters. This course is a great chance for students to get to interact with patients firsthand, and provides the resources NYU Langone, Rusk Rehabilitation, and the NYU Ability Project seek to help children with cerebral palsy. Bill sees this class as “very beneficial to students” and says, “I can see this class going on for years,” potentially taking on new projects using “OT ideas in the future to benefit patients through 3D technology.”
References
- Data and Statistics for Cerebral Palsy (Centers for Disease Control and Prevention)
- PLA vs. ABS: What’s the difference? (3DHub)