At the entrance to the prosthetics lab of the Holland-Bloorview Kids Rehabilitation Hospital, there’s a diorama showcasing prosthetics “under the sea”: a forearm hanging from a fishing lure, a leg decorated with a fish pattern. Sunlight streams through coloured glass slats while a skiing competition plays on screens alongside a poster for the War Amps Child Amputee program (called CHAMP). A little boy with a hot-pink cast wheels past reception staff pushed by his mom. “See ya later!” he hollers.
The lab is less like a stuffy hospital than a high school-shop class conceived by Dr. Seuss. It creates orthotics and prosthetics for kids with congenital or acquired anomalies and has developed devices for Paralympians such as sledge hockey players Greg Westlake, Bradley Bowden, and Billy Bridges. As one of the largest and most advanced prosthetic labs in Canada, Bloorview’s researchers are also developing new innovations in prosthetics powered by muscle murmurs (muscles emit a small, low-frequency vibration as they contract) as well as designing a knee joint for active kids—a particularly tricky endeavour. Using elements of engineering, robotics, medicine, anatomy, nursing, art, and kinesiology, the team also manufactures adaptive devices that allow for specific activities like playing ping-pong or riding a horse. The lab features a mill, a lathe, a sandblaster, rainbow-painted vacuum-pump machines, and a plaster room—“the messiest room in the hospital,” according to prosthetist team leader Shane Glasford.
To make a prosthetic limb, the prosthetist first wraps bands of plaster of Paris (a slurry which hardens like cement) around the residual limb (or stump), and uses that model to make a cast. The cast is then smoothed over, removing any ridges. From there it is taken to the lamination room and covered with PVA material, a “sock,” and resin, all of which gets curved around the cast with a vacuum. The result is a socket which follows the shape of the cast.
The socket is tested to see if it fits—the “sock” is what will affix to the residual limb; the rest of the device is attached to this point, and can include joints and skeletal components to create a functioning limb (in rare cases, the apparatus may even contain a computer system). For cosmetic purposes, the device can be covered by soft silicone parts to make it resemble a more realistic limb.
The kids get to choose their own decorations for their laminated sockets; options range from Batman to Lebron James. Prosthetist Kristen Matthews recalls a little girl who specifically wanted “Barbie shopping in a purple dress, with pink shopping bags, a pink purse, and a purple headband in her hair.” When presented with the finished product, “she was thrilled,” says Matthews. But the custom aesthetics aren’t always just cute characters. Glasford tells me about a little boy they’d outfitted with a new foot that included toes (his old prosthesis didn’t have any). He proudly showed it off, shouting, “Look grandma! I’ve got toes!” Says Glasford: “Nobody had a clue that it mattered to him, that it was important. But clearly, it was.”
HOLLAND-BLOORVIEW: BY THE NUMBERS
100-150: Minimum number of prosthetics made each year at Holland-Bloorview.
$20,000: Approximate cost for a transradial myoeletric prosthetic.
$40,000: Cost for a hand with independently moving fingers.
$8,000: Maximum cost of a silicone finger.
12 months: Average time a kid 3–15 years old will use a device before it needs replacing.
8: Number of people on Bloorview’s prosthetics team (four prosthetists and four technicians).
50 hours: Time it takes to make an average prosthetic arm (20-25 hours of manufacturing plus 20-25 hours clinical time).