Camera on a tripod records researcher and study participant talking in a lab with their backs to the camera while another researcher looks on.
Cindy Chestek, an associate professor of biomedical engineering at the University of Michigan, looks on as Karen Sussex, a study participant from Jackson, Mich., and Philip Vu, a biomedical engineering PhD candidate, discuss the next task in this lab session. The session is part of a prosthetic control study centering on the Regenerative Peripheral Nerve Interface, or RPNI.


Media Coverage

  • MIT Technology ReviewAn implant uses machine learning to give amputees control over prosthetic hands, 3/4/2020
  • ReutersProsthetic innovation: 'It's like you have a hand again' - study, 3/4/2020
  • ScienceMinimuscles let amputees control a robot hand with their minds, 3/4/2020
  • STATSurgery and AI give amputees more precise control of a prosthetic hand, study shows, 3/4/2020
  • WiredA deft robotic hand that’d make Luke Skywalker proud, 3/4/2020
  • EngadgetScientists develop neuroprosthetic tech that amputees don't need to learn, 3/5/2020
  • The ScientistPatients try most intuitive hand prosthetics yet in pilot trial, 3/5/2020
  • CBC Quirks & Quarks'It's like you have a hand again': A major breakthrough in robotic limb technology, 3/6/2020
  • Digital trendsProsthetics that don’t require practiceInside the latest breakthrough in bionics, 3/6/2020
  • Science FridayAll thumbs: A new trick for dexterity in prosthetic hands, 3/6/2020
  • MedicalXPress'It's like you have a hand again': An ultra-precise mind-controlled prosthetic, 3/4/2020

Meet the Researchers

Paul Stephen Cederna, M.D., is the Robert Oneal Professor of Plastic Surgery as well as a professor in the Department of Biomedical Engineering at the University of Michigan. His career has focused on the reconstruction of complex wounds, and his recent focus on the regenerative peripheral nerve interface is its latest form.

Cederna and fellow U-M researchers first hit upon the idea of utilizing muscle grafts as the connector between the brain and smart prostheses over a decade ago. By combining his clinical training in general surgery, microsurgery, and plastic surgery and background in biomedical engineering, he seeks creative solutions to enhancing functional restoration following limb loss.


Phone: (734) 936-5885


Research team:

Theodore Kung, M.D., assistant professor of plastic surgery

Stephen Kemp, Ph.D., assistant research professor of plastic surgery

Alicia Davis, C.P.O., senior prosthetist/orthotist

Ann Laidlaw, M.D., assistant professor of physical medicine and rehabilitation

Brian Kelley, D.O., professor of physical medicine and rehabilitation

James Leonard, M.D., clinical professor of physical medicine and rehabilitation

Carrie Kubiak, M.D., postdoctoral fellow of plastic surgery

Daniel Ursu, Ph.D., postdoctoral fellow from plastic surgery

Cindy Chestek, Ph.D., is an associate professor of biomedical engineering and a member of the Robotics Institute at the University of Michigan whose research centers on brain machine interfaces. That work is bolstered by a background that includes electrical engineering, computer engineering, as well as time spent in the neurosciences.

Before her collaboration with Cederna on RPNIs, Chestek only worked to harness prosthetic control signals directly from the brain. RPNIs represent an approach for restoring limb function that is less invasive than connecting with the brain and more effective than connecting directly to a nerve.


Phone: (734) 763-1759


Research team:

Philip Vu, Ph.D., postdoctoral fellow of plastic surgery

Deanna Gates, Ph.D., associate professor of kinesiology

Brent Gillespie, Ph.D., professor of mechanical engineering

Zachary Irwin, Ph.D., postdoctoral fellow of neurosurgery at Univ. of Alabama - Birmingham, former U-M biomedical engineering graduate student

Alex Vaskov, M.S., robotics Ph.D. candidate

Meet the Patients

Mike Moran, 45, worked as a professional painter when he lost his arm on the job. Humidity in the air caused his ladder to come in contact with the electricity from a power line.

Joe Hamilton, 30, lost his right arm in a 2013 fireworks accident. He was the first patient to undergo both the RPNI surgery and have electrodes implanted in his arm.

Karen Sussex, 53, lost her arm during unrelated emergency treatment at a hospital in 2015. She had previously worked at an injection molding plant, but is no longer able to perform the physical duties required.

The research team is looking for future participants for this and other studies. To be eligible for this study, you must live within 2 hours of the University of Michigan—Ann Arbor, be at least 22 years old, and have an upper limb amputation at the wrist or above. Other studies have different eligibility requirements. For more information, or to inquire about becoming a participant in the RPNI study, send an email to coordinator Kelsey Ebbs at and postdoctoral researcher Philip Vu at


Writing: Evan Dougherty

Multimedia: Steve Alvey and Evan Dougherty

Design: Scott Hyde and Amy Whitesall

Development: Nick Novak and Josh Walker

Editing: Nicole Casal Moore and Alison Wells

With support from Robert Coelius, Cara Gonzalez, Jim Lynch and the remainder of the University of Michigan College of Engineering Communications & Marketing Team


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