Emerging prosthetic technologies such as the DEKA Arm, the Johns Hopkins University Applied Physics Laboratory’s Modular Prosthetic Limb (MPL), and the Alfred Mann Foundation’s Implantable Myoelectric Sensor (IMES) often lead the way in gaining media coverage related to upper-limb prosthetics.
Multiarticulating myoelectric hands, for example Steeper’s bebionic3, Ottobock’s Michelangelo, and Touch Bionics’ i-limb, are the next most covered topic. The promise of dramatic functional improvements, including intuitive control, increased speed, multiple grips, and even a sense of touch, is engaging. But often, the less glossy, more practical realm of activity-specific prostheses is where people are actively living their lives, and gaining self-confidence along the way.
Prosthetists specializing in upper-limb prosthetics understand that this patient population includes many individuals who want to participate in exercise, sports, and recreational activities. Upper-limb specialist Pat Prigge, CP, FAAOP, clinical manager, Advanced Arm Dynamics (AAD) North Central Center of Excellence, Minneapolis, sees many people who want specialized prosthetic options that take them beyond standard activities of daily living. This became particularly evident to Prigge when he assisted on the upper-limb prosthetic team at Walter Reed Army Medical Center (WRAMC), Bethesda, Maryland, in 2008. “Life is about engaging in activities that bring joy, meaning, purpose, and release,” he says. “Having the ability to do the activities they love is what makes people feel complete and able. Frequently, it’s necessary to design a prosthesis specifically for a certain activity—a device that’s engineered to withstand the forces and work that’s required to accomplish that activity.”
Michael Kacer: Healing Through Sports
Retired Staff Sgt. Michael Kacer joined the Pennsylvania National Guard when he was 17 years old. At age 26, after deployments to Bosnia and Iraq, he was gravely injured during his 2008 tour in Afghanistan when an insurgent-fired rocket exploded next to him. He survived a traumatic brain injury, facial lacerations, a severed intestine, and the transhumeral amputation of his left arm. While recovering at WRAMC, he dropped from a physically fit 220 pounds to 132 pounds.
“From right after my injury, up to the point where I started getting my sports-specific devices, my family and my friends were the only thing holding what little bit of self-confidence I had intact,” says Kacer. “I had all of these thoughts like, ‘I’ll never get back to where I was. Without an elbow I’ll never be able to lift weights again or ride a bike again.’ Not only did I lose my arm, I was losing sports.”
The upper-limb team at WRAMC fitted Kacer with a body-powered arm and a transhumeral myoelectric prosthesis, which he says helped him feel more normal. But he says the aha moment came when he saw a person with a transradial amputation wearing an activity-specific device to connect to a weight machine. Kacer asked his prosthetist about creating a similar device, and he was fitted with a transhumeral sports utility socket with two D-rings on the lateral distal side that attached directly to the pulleys on weight machines. It worked the first time he put it on, and he’s still using it today. He then asked for a prosthesis that would allow him to return to mountain biking and was fitted with a device that features a FOX shock absorber mounted in the elbow and a TRS Hammerhead terminal device (TD) for securely locking onto the handlebar.
“I use my sports-specific devices more than any other prostheses I have,” Kacer says. “My cycling arm is also great for kayaking. The torque and the durability make it totally reliable, and the way I can adjust the elbow to wrist area is critical to getting the right angle. I can even put a lacrosse net on the end and go play catch with my nephew.”
Kacer has competed in the Warrior Games, medaled in the 2014 U.K. Invictus Games, and completed the Triumph Games triathlon of mountain biking, kayaking, and shooting. “Now I have random amputees contacting me on Facebook asking me for advice like, ‘What do I use? How do I do things?’” Kacer says. “And I have the confidence and knowledge to know that I can actually help them and inspire them to try new things.”
His current training is focused on qualifying for the U.S. Paralympics swim team so he can compete in the 2016 Summer Games in Brazil. “For me, being able to compete in sports has pulled me through and given me a sense of accomplishment,” Kacer says. “[C]onfidence is the secret to success in life.”
Amber Peterson: Just Like Any Other Kid
As Amber Peterson plays tennis and rides bikes with her friends, she is in every way a fit, fun, giggly 11-year-old. Unless someone pointed it out, you’d probably never notice she’s wearing a prosthesis on her right arm. That has a lot to do with the fact that Amber started wearing a passive prosthetic arm when she was an infant, and graduated to her first myoelectric hand at 18 months old. Two years later, she was fitted with a durable, activity-specific prosthesis so she could fully explore the expanding frontiers of childhood—the sandbox, summer at the lake, and her first attempts at baseball. By the age of four, she was taking violin lessons, relying on a unique TD designed for holding the bow at just the right angle.
Amber’s mother, Jennifer Peterson, remembers the day she learned that her baby, the youngest of four children and the only girl, would be born missing her right hand and forearm. “You have a dream of what your child is going to be like, and all of a sudden that dream has to change,” says Peterson. “And what I worried about was, ‘Is she going to be able to do what other kids do?’” Now, seeing Amber so engaged in basketball, volleyball, tennis, soccer, softball, swimming, and biking, she says she sometimes finds herself mesmerized by how well things are going. “I watch her run around and do all of the same things as her friends, and I realize I’m just standing there smiling, so thrilled that she can be a normal child.”
“My sports arm is called ‘Sporty,’” Amber says. “It has about ten attachments that I can change for different sports. Right now, my favorite thing is soccer because with my prosthesis, I do throw-ins. And I can be on defense because it’s usually the defender who does throw-ins, so it’s good.” Her TDs enable her to have the right tool for each task she seeks to accomplish. “With only my myoelectric arm, I think I wouldn’t be able to do a lot of things because it would be a lot harder,” Amber says.
According to Amber’s prosthetist, maintaining body symmetry is as important for people with limb difference as it is for those who have all their limbs. “When it comes to sports,” Prigge says, “it’s particularly important to have proper body posture and biomechanics to reduce the risk of injury. Imagine trying to swing a bat or go mountain biking with only one hand. Not only would these activities be more difficult, they’d be dangerous.”
Lauren Scruggs Kennedy: Moving Away From Trauma
Lauren Scruggs Kennedy doesn’t look like someone who would own a pair of boxing gloves. She does though, and for a few years in her early 20s, her passion for boxing was the thing that pulled her forward. “It literally was what I looked forward to every morning: get to the gym and start training,” she says. “I think that being active again increased my endorphins. I’d be at the gym for about two hours a day, and honestly, it was just like the main part of my life for a year and a half to two years.”
The other part of her life was more challenging—resting and healing as she recovered from a near-fatal accident in 2011 that resulted in the loss of her left eye and her left arm below the elbow. “I just had a lot of thoughts of ways my accident could hold me back, like, ‘I’m never going to be normal again, never going be able to do the things I was doing before,’” she says. “And I think the workout prosthesis shifted that perspective, and I was like, ‘Oh wow, I can do this!’ It’s obviously a new way of doing it, but it’s a lot better than I expected.”
Kennedy’s prosthetist, Rob Dodson, CPO, FAAOP, clinical manager, AAD Southwest Center of Excellence, Dallas, fitted her with an activity-specific prosthesis and three interchangeable TDs from TRS, Boulder, Colorado: the Shroom Tumbler, the Dragon, and the Kahuna. All of these devices connect into a United States Manufacturing Company (USMC)-style Hosmer quick disconnect wrist. “Lauren uses a locking liner for suspension,” he says, “and the socket incorporates a Boa system to provide adjustable medial-lateral compression around her arm. These types of devices allow people to do the kind of activities that define who they are, giving them a feeling of normalcy that other prosthetic options simply cannot.”
Kennedy says her favorite TD is the Shroom Tumbler, and she uses it for almost everything in the gym, including doing push-ups, handstands, and Pilates, and she even hooks it to the handles of weight machine pulleys. For boxing, she wears the socket without a TD inside her glove. For everyday use, Kennedy has a high-definition passive restoration that closely resembles her sound hand. “I’m really all about realistic-looking prostheses,” she says, “My workout prosthesis doesn’t look real, but I love it and don’t know what I’d do without it. It just adds a lot of energy and confidence.”
Dave Newkirk: Athlete, Coach, Mentor
At 42 years old, Dave Newkirk says he has found his mojo. He’s passionate about competing as an adaptive athlete, coaching children with upper-limb differences, and mentoring adaptive athletes. He was born without a left hand and wore a body-powered prosthetic hook until he was about five years old. The next time he put on a prosthesis he was 16. It was a passive arm, and he only wore it when he played volleyball. A self-described “hypercompetitive sports nut,” Newkirk competed with the U.S. Paralympics standing volleyball team in the 1992, 1996, and 2000 Paralympic Games. More recently, he has shifted his athletic focus to the gym and CrossFit-style competition. “Back in 2013, I got involved with Crossroads Adaptive Athletic Alliance and competed in the Working Wounded Games,” he says. “I was hooked. I made my garage into a commercial-strength conditioning center, and I do all my training there. It’s great—it’s open 24 hours a day.”
He uses multiple TDs that connect to his transradial socket: the Shroom for doing push-ups and floor exercises; the TRS Black Iron Trainer for holding barbells; a TRS MaxGrip barbell attachment for bench pressing and lifting overhead barbells; and a lengthening attachment with a ratcheting clamp for using gymnastic rings. All of these are specifically modified for proper length with custom-made lengthening attachments using ½-inch x 20-inch bar stock and coupling devices. “I get together with Rob, my prosthetist, and we rough out designs on the whiteboard. It usually comes out of my head, through his hands, and back onto my arm. Being allowed to be part of the design process is absolutely key for me.”
Newkirk has held adaptive workshops with support groups for individuals with upper-limb differences, and in July, he was a coach at NubAbility Athletics’ All-Sport Summer Camp for children with limb differences. “Working with kids is a huge passion of mine and has really been my focus the last three or four years. There’s still time to help them grow and develop the right way versus how I grew up, which was growing and developing without using prostheses,” he says. “They can actually harm themselves trying to be active without the right prostheses, and that costs a lot more from a healthcare standpoint than providing them with a device that will make them more functional and healthy.”
Activity-Specific Prostheses Help People Thrive
Activity-specific prostheses are empowering people with upper-limb loss/difference to move in bold, new directions. It might be a child who steps away from the bench and onto the playing field, or an adult who discovers that being physically fit is what restores his or her hope and enthusiasm for life. Beyond sports and recreation, activity-specific designs help people enjoy doing crafts, cooking, gardening, working with tools, and more. These devices link people to an array of health benefits like body symmetry, improved musculoskeletal alignment, weight management, reduced overuse of the sound side, improved wellness, and an increased sense of confidence and capability. Prosthetists who specialize in upper-limb prosthetics have the experience and clinical expertise to help people reinvent their lives with unique, activity-specific devices.
Sherri Edge is a writer and video producer based in Oklahoma City, and has written about prosthetics for more than 20 years.