12-year-old California amputee surfs again with 3-D-printed ‘water leg’
Natallie Rocha | San Diego Union-Tribune
Jonah Villamil jumped on a surfboard with two legs for the first time in three years in June. He was putting his new 3-D-printed prosthetic leg to the test.
Jonah refers to it as his “DNA leg” due to its twisted structure.
“There’s a bunch of lines on it that (the water) will just go through,” the 12-year-old Chula Vista resident explained. “It wasn’t like it was weighing me down.”
It’s not the first time he’s experimented with a prosthetic leg. But it was the first time he’d played in the ocean with a leg made by Limber Prosthetics and Orthotics, a UC San Diego startup that’s gaining funding.
Below-the-knee prosthetics are created by the company using an iPhone app that scans the patient’s limbs. Limber then sends that data to a 3-D printer, which produces a precise, customized prosthetic leg faster than traditional methods.
“I think one of the reasons why I fell in love with this specific project is that there’s a really tangible, direct impact — that’s sometimes difficult to get in other industries,” said Joshua Pelz, Limber’s co-founder and CEO. “You could work in another industry and have a big impact on people’s lives.” However, it may not be as tangible as providing someone with a device that allows them to get back on their feet and resume their lives.”
The Limber UniLeg was conceived in a UCSD classroom in the spring of 2019. The task was to solve a global problem using lab technology such as digital design programs and 3-D printing.
According to the World Health Organization, approximately 40 million people in developing countries are amputees, with only 5% having access to prosthetic care. Part of the problem is that traditional prosthetic limbs are handcrafted, making the cost and time required for care inaccessible to many people.
Pelz met his Limber co-founders Luca De Vivo Nicoloso and Herb Barrack while working on his doctorate in engineering. De Vivo Nicoloso was a doctoral student in engineering, and Barrack, a certified prosthetist and orthotist with nearly two decades of experience, was a subject matter expert assisting students.
They collaborated with their professor to create the first Limber UniLeg prototype, using a combination of materials that are stronger than regular plastic but allow the leg to maintain varying levels of stiffness and flexibility.
The Limber leg’s swirled, single-body design is not only cool, but it was inspired by the lightweight durability of a chollas cactus. As part of his doctoral engineering thesis, De Vivo Nicoloso investigated the plant’s structure and applied its ability to withstand high desert winds to the Limber UniLeg.
The Limber UniLeg is one piece, as opposed to a traditional prosthetic limb, which is made up of multiple components and tons of tiny metal screws.
For more than 20 years, Barrack, Limber’s chief medical officer, has made regular trips to Ensenada, Mexico, to assist amputees who cannot afford prosthetic care. Limber’s founders brought their prototype on one of these trips a few years ago and were able to deliver prosthetic limbs to the community.
The trips to Ensenada solidified Pelz and De Vivo Nicoloso’s desire to turn this class project into a sustainable business that makes prosthetics more accessible.
“It was staring us in the eye when we fitted our first patients outside the classroom that we realized, ‘wow, if we really can do this at scale, we will be able to help millions of people,'” said Limber’s chief financial officer, De Vivo Nicoloso.
Limber will go public in 2020.
The company began in someone’s garage, as have so many innovations throughout history, from the Etch A Sketch to the Dyson vacuum. Limber’s first two 3-D printers were built in Pelz’s garage.
“It’s just kind of been grinding, pedal to the floor, going as hard as we can, working on weekends to bring this thing into reality because it needs to be improved,” Pelz said. “It’s a global crisis, and we’ve witnessed it firsthand.” And we’re thrilled to be able to make a difference.”
The hard work has paid off.
Surprisingly, Limber is raising funds in a high-interest-rate environment where venture capital is not flowing into startups as it did earlier in the pandemic.
Limber won the San Diego Angel Conference’s top prize in May, an annual gathering of hundreds of early stage companies and investors from across the country. That first-place finish also came with a $263,000 investment, which has since grown.
UC San Diego recently invested $250,000 in Limber. Limber has raised approximately $1.2 million to date.
Limber will use the funds to build more 3-D printers, expand its capacity, and relocate to a larger lab space off-campus. It will also fund clinical trials for the device, as well as submit an application to the FDA and launch a commercial product next year.
Limber currently operates three printers and intends to construct five more by the end of the year. Pelz stated that the company’s goal for 2024 is to sell 200 legs in the United States. They are still working on a strategy for international expansion.
Limber has fitted 36 patients with varying levels of activity and ages ranging from 3 to 75 years old, according to Pelz.
Limber received a lot of media attention last summer for bringing five prosthetic limbs to Ukrainian soldiers fighting in the war against Russia, emphasizing the need for more capacity. While the founders’ trips to Mexico continue and they hope to help people in developing countries with their products, the company’s primary focus right now is on developing a sustainable business model in the United States.
“This is not only for people in need,” De Vivo Nicoloso explained. He went on to say that the device is not a “cheap alternative” to traditional prosthetics, but rather another way to improve patients’ quality of life and how clinicians make prosthetics.
Limber is not a customer-facing company. Instead, the company provides digital design and manufacturing assistance to clinics that make prosthetics. Limber is still building its network of certified clinics and has yet to determine the UniLeg’s price and whether it will be partially or completely covered by insurance.
According to Jesus Mendoza, a local certified prosthetist and orthotist who referred Jonah to Limber, it’s not a perfect, one-size-fits-all solution for anyone with a prosthetic limb. Mendoza is a longtime friend of Barrack, one of the Limber founders, and he recognized the design’s benefits for specific use cases.
For someone like Jonah, who needed his left leg amputated in 2020 due to a sudden infection that landed him in the hospital, it’s given him another way to stay active.
Jonah’s passion for sports such as wrestling, basketball, and jiu-jitsu inspired him to embrace being active with a prosthetic limb. He’d been requesting a “water leg” from Mendoza because he enjoys surfing and hiking with his family.
“I just knew Jonah was a champion, so whatever we did, he was going to make it better,” said Mendoza, whose family business, ABI P&O, has been assisting people in need of prosthetic limbs for nearly 30 years.
Mendoza works with many pediatric patients, including Jonah, and mentioned one advantage of the Limber system. Clinicians must adjust prosthetics on a regular basis, especially for children who are constantly growing and changing. Mendoza likes that the Limber technology allows him to take precise measurements and track any changes digitally, which helps him justify the frequent changes with medical providers and insurance.
Traditionally, prosthetists take plaster cast impressions of patients, take manual measurements, and modify everything by hand, he explained. These processes are now being gradually digitized across the industry. Mendoza went on to say that while the incorporation of digital software is not unique to Limber, the startup is streamlining the workflow. Mendoza is also optimistic about Limber’s potential to provide a more accessible option for patients who require prosthetic limbs, regardless of insurance coverage. He stated, for example, that the use of individual 3-D printed components in prosthetics has been shown to be less expensive than some traditionally manufactured parts, which can cost thousands of dollars.
Below-the-knee prosthetics can range from $5,000 to $15,000, but prices vary greatly depending on insurance coverage and device brand, according to Mendoza.
Limber is still in its early stages, so more testing on durability is needed to determine what applications it might be suitable for, according to Mendoza. Finally, when discussing prosthetics with their clinician, it comes down to patient preference for how different prosthetics feel.
“I don’t think this is the right leg for everybody,” he admitted. “However, I believe it will be part of the clinicians’ and doctors’ decision-making about who is a good candidate for this, but it will definitely add more to our toolbox and patients’ options.”
When Jonah first tried on the UniLeg at the Limber lab, he raced up four flights of stairs with his brothers, skipping every other step. He’d only been wearing the new 3-D printed prosthetic leg for about an hour.
“It looked natural on me,” he said, adding that it was much lighter than his traditional prosthetic leg.
Jonah was able to return to the ocean after being fitted for a Limber prosthetic leg.
Rhodalyn Villamil, his mother, was overjoyed to see him carrying his surfboard to the water on his own. He was born in the summer, so he’s always been a “water boy,” according to her.
“It was good for me,” said Jonah. “Like just knowing that because it’s plastic, I’ll be able to use it for more than just walking around.” I won’t have to clean it as thoroughly because there are only a few ridges to clean, and I’ll be able to surf and swim with it without having to remove my leg.”
