Next Gen Limb Design

For 130 years, Winkley has helped make Minnesota a hub for prosthetics and orthotics

Robert, the seven-axis robotic limb carver at Winkley Prosthetics // Photo by Harrison Barden

Robert, the seven-axis robotic limb carver at Winkley Prosthetics // Photo by Harrison Barden

Inside a glass cube, Robert grinds away at a leg, swiveling his head from side to side, slowing down to carve the fine details of the ankle bone and arch, occasionally pausing to blast the leg with air and clear the dust. 

Robert lives in Golden Valley. He is a five-foot-tall workhorse—indispensable, dead accurate, able to out-sculpt any of his human counterparts. Robert is not, however, a human. He is a seven-axis robotic carver, one of only three being used in the industry nationwide, and he belongs to Winkley Orthotics & Prosthetics, the oldest privately owned orthotics and prosthetics company in the country—and the largest in Minnesota. 

Long before Robert existed, if you had a railroad or farming accident or, more commonly in the former flour capital of the world, a milling accident, there were no professionals around to help guide amputees through the arduous process of getting fitted with new limbs. You had to seek the help of a woodworker or other craftsperson—many of whom were themselves amputees, and who had taken to the practice in search of more comfortable options. They fashioned arms and legs from wood, leather, and steel, and it could take up to a year to get the custom limb from the carver. 

That was the situation in Minnesota until the late 1800s, when artificial limb companies started popping up in Minneapolis. By 1918, most likely spurred by the dangers of the various local industries, competition, and the city’s central location—not to mention the aftermath of World War I—Minneapolis had become a hub for artificial limb companies, including the Minneapolis Artificial Limb Company and Winkley Orthotics & Prosthetics, then known as The Winkley Artificial Limb Company. 

A craftsman and amputee works on a wooden limb at the Minneapolis Artificial Limb Company in 1918 // Photo by Charles P. Gibson, via Minnesota Historical Society

Winkley was founded in 1888 by Lowell Jepson and Albert Winkley, the former being the marketing and business guru of the operation, the latter a farmer-turned-inventor. Winkley first set up shop in what is now Gateway Park, at the west end of the Hennepin Avenue bridge, before opening a bigger factory on Washington Avenue. 

Many changes have taken place in the company since Winkley’s early days. At first they expanded nationally, sprouting clinics on the East Coast and all over the Midwest. But by the 1960s, it became too difficult to manage the myriad satellite locations, so Robert C. Gruman—the inspiration behind the name of the seven-axis carver—reeled the business back to Minnesota. Since 1977, Winkley has manufactured orthotics and prosthetics from their Golden Valley location and currently have nine clinics, two of which are in Wisconsin, and 60 employees. “We’ve stayed alive and relevant by putting the patient first,” president and co-owner Alex Gruman says. “And we treat employees well. It’s sort of a family.” 

Gruman and his sister, Amalia Gruman Laird, the company’s vice president and co-owner, represent the fifth generation of family owners. (Jepson was their great-great grandfather.) Both started the same way anyone at Winkley starts: as entry-level lab technicians, later working their way up to eventually becoming licensed clinicians. 

Amalia Gruman Laird, Winkley Prosthetics vice-president and co-owner, left, and Alex Gruman, president and co-owner right // Photos by Harrison Barden

Laird is a certified prosthetist; Gruman is an orthotist. Or, as Gruman puts it, “she’s fake legs and arms, and I’m braces.” Both see patients and, despite the weight of ownership and family lineage, seem more comfortable chatting with lab technicians in the back room or jumping in to help pull a sheet of thermoform plastic from an infrared oven than they do answering big questions about family history.  

Long gone are the days of woodworkers, amateur inventors, and DIY tinkerers. Plastics were implemented in the ’60s and ’70s, and resulted in much lighter, more comfortable orthotics and prosthetics. After that came laminates and fiberglass and carbon fiber, which, although strong and durable, were also relatively lightweight. Nowadays, prosthetics are utilizing microprocessors and hydraulics, and sockets are made from a lamination of nyglass, a fiberglass and nylon material, and carbon fiber with epoxy acrylic resin. The manufacturing lab at Winkley has a distinct smell of science: hot plastic and glue, coupled with the astringent tang of heated metals and rubber—some amalgam of a college physics classroom and construction zone. 

The current product has essentially been the same for a while, Gruman says. “No one wants to change to these new products; change is scary,” he explains. “And then you have old practitioners and you’ve got old patients who say, ‘I don’t want that new stuff.’ So, it takes a while for us to get used to it and for others to get used to the ideas.” 

When asked about major shifts in technology, Laird and Gruman respond in unison: “Microprocessor knees.” 

 A below-the-knee Genium microprocessor prosthetic // Photo by Harrison Barden

A below-the-knee Genium microprocessor prosthetic // Photo by Harrison Barden

“When microprocessors came around, it made it much safer for patients and was able to help them if they were to stumble or fall,” Laird says. The siblings grow excited about the technology and start finishing one another’s sentences. “The microprocessor can predict what’s going to happen,” Gruman says, quickly followed by Laird’s, “Yeah, now there’s more gyroscopes and sensors in there,” a thought then finished by Gruman: “So as you walk, it adjusts the tension so it keeps your leg stable.” 

And just what is a microprocessor? “It’s a tiny computer,” Laird says, smiling. 

 Microprocessor knees were introduced in the late ’90s and early 2000s, and the technology continues to grow more sophisticated. Now implemented with sensors and gyroscopes, the knee knows when you’re sitting and when you’re going down stairs. They are also Bluetooth enabled, allowing users to control settings from their phone, putting the knee in biking mode or running mode, for example. 

A new prosthetic begins with a 3D scan or a plaster cast, depending on the patient and the nature of the prosthesis. The plaster cast is then filled and modified by hand, or, if the patient is a good fit for scanning, clinicians can make changes digitally. Then the positive limb is carved out of a light, dense foam by Robert and plastic is thermoformed over the model to make a test socket. 

 A lab tech demonstrates 3D scanning // Photo by Harrison Barden

A lab tech demonstrates 3D scanning // Photo by Harrison Barden

Hand-applied touches done with Trautman grinders follow and, when it’s ready, the patient is fitted with the socket. After a round or two of adjustments and alignments, the patient is sent home for a trial run. Once everything fits and works well, there are more alignments and plaster molds, laminations, chipping and trimming, and, finally, follow-ups for socket modification. 

Though the process is intensely systematic, the artistic element of it all isn’t entirely absent. New lab techs fresh out of school might bring new ideas, changing up the lamination “recipe,” for instance, or introducing new methods. “They don’t always work,” Gruman says, “but sometimes they do. We’re always open to new ideas and new technologies.” This openness, along with the people-first mentality, seems essential to Winkley’s success.

Lab techs laying laminate over a limb // Photo by Harrison Barden

Lab techs laying laminate over a limb // Photo by Harrison Barden

When asked about patient success stories, though, Laird hedges. Stories of famous athletes with prosthetics—like snowboarder Amy Purdy or surfer Bethany Hamilton—are rare in the industry. Instead, she considers a patient simply using their prosthetic every day to be a huge success, because some might not use it at all. “Everybody goes through a grieving process, and it takes them a while to bounce back,” Laird says.

She’s being modest, no doubt due to being reminded daily of the emotional toll involved with limb loss and congenital conditions. One look around the clinic, though, and it’s obvious that Winkley’s reach goes far. Action shots of athletes are signed with effusive gratitude. Lab techs constantly consult one another, carrying themselves with an enviable lightness. And it’s difficult to dismiss the epic legacy: when asked if they felt any pressure to carry on the family business, Laird and Gruman immediately say, “No, not at all.” 

Whatever the recipe for success, Gruman and Laird exude everything you’d want in a boss: professionalism, deep knowledge, relatability, and a genuine interest in helping their employees (and the orthotics and prosthetics field as a whole) advance. “We find ourselves walking behind people in the mall and analyzing their gait, thinking, ‘Oh, you could use a foot orthotic,’ or, ‘You need a custom AFO [brace],’” Gruman says. “Where is that? Where did your doctor fail you?” Laird says they feel spoiled being able to walk into the lab right after a patient consultation. “If the patient is picky or particular,” she says, “we can walk right into the back and talk it over with the lab techs.” 

There’s not an ounce of denigration in her voice when she says “picky” or “particular,” either, which echoes Gruman’s earlier sentiment: “Patient first,” indeed.