mission driven innovation in small joint orthopedics


More than 20 million people in the US have symptomatic hand arthritis. Five million are actively seeking treatment to relieve pain and preserve motion. 

The majority are excluded from electing joint replacement surgery (arthroplasty) because of active lifestyle demands or inadequate stabilizing tissue in their finger joints.  High risk and unpredictable outcomes for current devices leave an estimated 1 million advanced stage arthritis patients with no good treatment options.  

Lifejoint was founded by a hand trauma patient and surgeon to answer this underserved market. We are developing a new joint replacement device to relieve pain and preserve motion for osteoarthritis, rheumatoid arthritis, and post-traumatic hand arthritis patients. 

gardening hands, construction worker, piano hands, weightlifter

Early Interest

Patient interviews

"My surgeon described the unpredictable outcomes and risks with finger joint replacement today. I said, no way!"

"I just take a lot of Meloxican and hope it doesn't burn a hole in my stomach."

"My wife has bad osteoarthritis in her hands. The pain bothers her all the time. She's tried wax baths. I had two hips replaced for arthritis. Successful joint replacement is life changing. It is a shame my wife can't get the same outcome for her hands."

Hand Surgeon interviews

“If I had a device that performs predictably well, is easy to insert, eliminates pain and preserves motion, I would be doing it all the time. We all would. It would be the bulk of my practice.”

"Pyrocarbon surface replacements squeak & dislocate, Swanson silicone hinge is not strong in colateral plane - do not have any good option. Djit option - that's interesting, novel, we need it. "

"Ease of use for surgeon a good feature… idea is totally novel. "

"We don’t even use the two-piece surface replacement device in Canada; expensive, unproven "

"…could be used to reverse a fusion."

Core Team

  • Marcia Hart

    CO-FOUNDER / CHIEF EXECUTIVE OFFICER

    Marcia Hart is a lifelong inventor, maker and entrepreneur. Her unusual career launched with a Master of Architecture degree from Harvard Graduate School of Design (GSD) and includes professional expertise and extensive networks in design and engineering, consulting, and entrepreneurship. In addition to Lifejoint, Ms. Hart designs and fabricates custom furniture in wood and steel. A table saw accident opened the door to partnership with Dr. Katz.

    Harvard Graduate School of Design, M.Arch.
    Princeton University, B.A. Architecture
    Phillips Exeter Academy

  • Dr. Ryan Katz, M.D.

    CO-FOUNDER / CHIEF MEDICAL OFFICER

    Dr. Katz is a Johns Hopkins trained plastic surgeon who completed a hand surgery fellowship at the Curtis National Hand Center in Baltimore. With several of his cases having garnered media attention, he is known for his innovative approaches to complex upper extremity reconstruction. He currently teaches the principles and practice of hand surgery to plastic and orthopedic surgeons who aspire to become hand surgeons. He has dedicated himself to optimizing patient outcomes and to advancing the science of surgery when it comes to the most challenging of cases.

    Curtis National Hand Center, Fellowship
    Johns Hopkins Hospital, Internship and Residency
    University of Maryland Medical School, M.D.
    Duke University, BS/BA

  • Mary Wentorf, B.A.

    CHIEF TECHNOLOGY OFFICER

    Mary has 25 years of global experience developing orthopedic & cardiovascular medical devices. She has held leadership roles in new product development, marketing, regulatory, quality, operations, clinical application engineering, and business development variously with DePuy Synthes, Zimmer, Boston Scientific, Guidant.

    As an engineer, Mary is an expert in total joints (hips, knees, shoulders) with a specialization in revision and endoprostheses, trauma and deformity correction. She holds over 40 patents.

    Having worked at companies of all sizes, Mary understands the importance of integrating design controls, risk management, regulatory strategy, clinical data, and product-market fit into the role of CTO.

    University of Minnesota, B.S. Mechanical Engineering

  • Fred Wentorf, Ph.D.

    DIRECTOR OF RESEARCH

    As Chairperson of the Department of Engineering and Associate Professor of Engineering at Grace College in Winona Lake, Indiana, Fred is ideally situated to lead academic research for Lifejoint. Located in the global heart of the orthopedics industry, Grace College boasts a state-of-the-art research facility under Fred's direction. Prior to his current academic appointment, Fred was Principal Research Engineer at Zimmer, responsible for testing of orthopedic implants in development.

    At Lifejoint, Fred is responsible for design inputs, prototype manufacturing, testing plan and execution, and support of new product development and regulatory submissions. Fred is Lifejoint's Principal Investigator (PI).

    Goshen College, B.A.
    Case Western Reserve University, B.S., M.S.
    University of Minnesota, Ph.D.

  • TBD

    Engineer - New Product Development (NPD)

  • Fraser Smith, Ph.D.

    CO-INVENTOR

    With over 150 patents , Fraser’s experience in value creation is a huge asset for Lifejoint. Throughout his career, Fraser has been responsible for winning contracts and developing innovative mechanical engineering solutions for defense, entertainment, and medical device industries. He is a co-founder of Sarcos, former President of Raytheon-Sarcos, and President/CEO of Raytheon’s spinout Sarcos Robotics, now Palladyne AI.

    University of Utah, Ph.D. Mechanical Engineering
    University of Toronto, MS, BS Mech. Eng.
    Phillips Exeter Academy

  • Allan C. Doyle

    DESIGNER

    Allan Doyle leverages advanced CAD software to explore new ideas with digital modeling and simulation. His easy facility using the most advanced features in Rhino, Grasshopper, SolidWorks, Fusion360, and 3D printing tools allows Lifejoint to visualize and present design options at the earliest possible stage, to solicit feedback from surgeons and other experts.

    Maryland Institute College of Art (MICA), B.A.

Contact us

Hand surgeon, patient, engineer, medtech investor, advisor, friend:
We want to hear from you.