First Truly Bionic Leg: Better, Stronger, Faster


SALT LAKE CITY, Utah. (Ivanhoe Newswire)— There are more than two million people living with limb loss in the United States and that number is expected to double by 2050. Whether it’s the result of a disease or an accident, having a limb amputated changes your life— drastically. People never know the moment their lives will change … But for one young man—he has video of it. Bionic leg

This is the moment Alec McMorris’ life changed forever.

“That was kind of the last time that I took steps with two feet,” McMorris recalled.

Alec was removing a tire from the road when a car sent him flying 30 feet. Alec lost his leg but gained a new perspective.

“This gave me a lot of direction, a lot of drive,” McMorris shared.

Alec was called on to be the first person in the world to test the first truly bionic leg.

McMorris expressed, “I love anytime I get the call to go up there, what are we going to push today? What boundaries are we going to try to test?”

The leg is designed to be lighter, stronger, and faster than any prosthetic invented before.

Tommaso Lenzi, PhD, director of the bionic engineering lab and assistant professor in the department of mechanical engineering at University of Utah stated, “It’s the first device that can really replicate the biomechanical functional of the biological legs.”

(Read Full Interview)

 Lenzi’s team at the University of Utah is creating the self-powered prosthetic leg with computer processors and motorized joints in the ankle and knee. Smart sensors pick up electrical signals from the skin.

“It looks if there’s load on it, if it’s moving in the space, if it’s impacting the ground. And that’s one thing that it does to understand what the user wants to do,” Lenzi explained.

Based on that real-time data, it provides power to the motors in the joints to assist in walking, standing up, and walking stairs.

“We’ll do a test or something and Dr. Lenzi will look at me and be like, well, now you’re the fastest person to ever walk on a power leg in the world,” recalled McMorris.

Now Alec’s using what he’s learning in the lab and transferring it to the playing field as an assistant coach.

“Teaching yourself boundaries, accountability, discipline, how to work hard,  how to work through adversity when hard things hit,” expressed McMorris.

Tommaso Lenzi and his team just received two grants to further advance the technology. One is a 2.2 million-dollar award from the National Institutes of Health and the other a $600,000 grant from the National Science Foundation. If all goes well, he hopes to get it on the market in the next five years.

Contributors to this news report include: Cyndy McGrath, Executive Producer; Marsha Lewis, Field Producer; Rusty Reed, Videographer; Roque Correa, Editor.

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REPORT:       MB #4823

BACKGROUND: There are nearly two million people living with limb loss in the U.S. The main causes of limb loss are vascular disease, including diabetes and peripheral arterial disease, trauma, and cancer. Approximately 185,000 amputations occur in the U.S. each year. People can lose all or part of an arm or leg for several reasons. Common ones include problems with blood circulation. These may be the result of atherosclerosis or diabetes. Severe cases may result in amputation. Injuries, including from traffic accidents and military combat, cancer, and birth defects are other common reasons. Some amputees have phantom pain, which is the feeling of pain in the missing limb. Other physical problems include surgical complications and skin problems from the artificial limb.

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GETTING A PROSTHESIS: While many people with limb loss do well with their prosthetic legs, not everyone is a good candidate for a leg prosthesis. The type of amputation can affect the decision. It’s generally easier to use a below-the-knee prosthetic leg than an above-the-knee prosthesis. The reason behind the amputation is also a factor, as it may impact the health of the residual limb. Physical health and lifestyle are also important to consider. There have been new developments in prosthetic limb technology. Microprocessor joints feature computer chips and sensors to provide a more natural gait. There are also specialized prosthetic legs for different activities, such as running, showering, or swimming, which you can switch to as needed. Osseointegration surgery is another option. This procedure involves the insertion of a metal implant directly into the bone, so there is no need for a socket.


NEW BIONIC LEG: Tommaso Lenzi, PhD, mechanical engineer at University of Utah, and his team at the Bionic Engineering Lab developed a new adaptive controller for their Utah Bionic Leg. The Utah Bionic Leg is a computerized and motorized prosthetic for leg amputees that is powered and can help users walk with ease. It uses custom-designed force and torque sensors as well as accelerometers and gyroscopes to help determine the leg’s position in space. Lenzi and his team developed a new controller that adapts to the movement of the user. This controller continuously looks at the user’s movement and updates the trajectory of the robotic leg 1,000 times each second to replicate what the biological leg would do in similar conditions. “Like the biological leg, with this controller each step is different,” Lenzi said. “When the user encounters an obstacle, he or she can just cross it by doing what they would do with their biological leg. No need to stop and go around it.”





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Doctor Q and A

Read the entire Doctor Q&A for Tommaso Lenzi, PhD, director of bionic engineering lab, assistant professor

Read the entire Q&A