A year ago at this time we shared the story of Marc Dunshee, the first (and only, as far as we knew) user of a hemp socket. He’s not alone anymore: Human Plant Solutions, the Kansas startup that created his device, is open for business. They started selling to the general public about two months ago.
As you might recall from our article last year, Dunshee touted the hemp socket’s comfort, fit, and durability. He’s worn the original prototype for roughly five years, putting that venerable unit through a Boston Marathon, a handful of triathlons, a bevy of 5Ks and 10Ks, and countless weeks and months of daily fitness runs.
“People talk about carbon fiber’s extreme high tensile strength, and that’s important,” says Kyle Trivisonno, Human Plant Solutions’ co-founder. “But high tensile strength comes with inherent brittleness, so impacts aren’t as friendly. When you’re developing a socket, you want something that has a little more flexibility, and the ability to compress without failure.”
According to Trivisonno, a hemp socket offers the strength of carbon fiber (it’s actually stronger, when properly treated) in a more supple, elastic, lightweight package. The comparison is akin to the difference between running on asphalt versus running on a gravel path: The more forgiving the surface, the less wear and tear on the body. And because it’s less corrosive than carbon fiber, hemp also takes less of a toll on prosthetists and technicians—and on the planet, for that matter.
All those objectives led Trivisonno to start experimenting with plant-based fibers about six years ago, while he was working as a prosthetic technician at a North Carolina clinic. He spent several years refining the design, with the 44-year-old Dunshee (a left below-knee amputee) as his primary tester. Human Plant Solutions relocated to Kansas in late 2020 to take advantage of some R&D partnership opportunities at nearby Wichita State University. The company also connected with the local VA, working with a cohort of amputees and prosthetists to perfect HPS’s product specs and fabrication processes. Last November, the firm quietly started accepting orders.
“We’re fully functional for central fabrication,” says Sam Spallitta, the company’s co-founder and CEO. “It’s pretty much a plug-in technology for the industry, no different from ordering a carbon-fiber socket.” Consumers shouldn’t notice much difference, he says—your prosthetist will make a test socket, overnight it to Human Plant Solutions, and get the fabricated hemp socket back a few days later. Final fitting and adjustment takes place at your prosthetist’s office, same as ever.
“We really respect the relationship between practitioner and patient,” Spallitta says. “We don’t want to get in the way of that. We want to introduce this new technology without asking people to change what they’re used to.”
Spallitta and Trivisonno will be the first to tell you the hemp socket is still a work in progress. “When it comes to sockets, there isn’t a ton of great data out there that allows practitioners to evaluate the performance of carbon versus any other material,” Trivisonno says. “There are some ISO tests out there for evaluating knees and feet and things like that, but nothing for sockets. We’re doing a series of tests with Wichita State’s engineering department, and hopefully we’ll have some results ready to publish fairly soon.”
In addition to driving improvements in socket design, those data may also suggest other potential applications for hemp within O&P. “We’re just excited to start the industry down the path of sustainability,” Spallitta says. “We’re doing a lot of R&D right now for companies who have ideas for how to implement natural fiber into other componentry that goes into prosthetics. The technology we’re working on is geared toward giving patients better, more active lifestyles and better mental health. That’s the reason we named the company Human Plant Solutions—we’re about people, utilizing plants, to create solutions.”
If you’re interested in giving the hemp socket a shot, have your regular prosthetist get in touch with Human Plant Solutions. Contact info is at humanplantsolutions.com.