ETH Zurich creates 3D bioprinted tissue bridges for better prosthetics

Researchers at ETH Zurich have developed a breakthrough biohybrid system that combines synthetic and biological materials to replicate the natural interface between bones and muscles. This innovation could transform medical robotics and implants by solving the critical problem of poor force transmission between biological and artificial components, potentially leading to more effective prosthetics and human-machine interfaces.

What you should know: The team created a 3D bioprinted actuator that structurally and functionally mimics the natural connection between muscle and bone, addressing energy losses at biological-synthetic interfaces.

• Researchers developed a tendon made from printed cell tissue with stiffness levels between living muscle and bone-mimicking rigid segments.
• The system replicates the structure of tendons and their transition to muscle (the myotendinous junction) using living biological tissue.
• Initial tests showed the 3D bioprinted actuators demonstrated reliable and long-term stable contraction ability.

How it works: The biohybrid system uses 3D bioprinting technology with muscle cells and specialized anchoring structures to create functional tissue interfaces.

• Living actuators are created using muscle cells and tendon-like anchors containing connective tissue cells printed onto a platform.
• Computer-assisted analysis optimizes the shape and structure of each actuator for maximum efficiency.
• The approach mimics biological tissue structure and function while enabling improved integration with technical systems.

In plain English: Think of this like creating a bridge between two different materials—biological tissue (like your muscles) and artificial parts (like a robotic limb). Normally, these materials don’t work well together because they have different properties, causing energy to be lost when forces are transmitted between them. The researchers essentially 3D printed living tissue that acts as a perfect connector, similar to how tendons naturally connect your muscles to bones.

Why this matters: Current medical implants and robotic systems struggle with inefficient force transmission at the interface between biological and synthetic materials, leading to energy losses and reduced functionality.

• This breakthrough could enable enhanced human-machine interaction across healthcare, medicine, and robotics applications.
• The technology addresses a fundamental challenge that has limited the effectiveness of current prosthetics and implants.

Future applications: The research team has identified several promising medical applications for their biohybrid technology.

• Biomechanical modeling of the middle ear, specifically the interaction between the stapes bone and stapedius muscle.
• Development of adaptive prosthetics that better integrate with human biology.
• Creation of biologically integrated robotic systems and lab-grown replacement tissues.

Who else is involved: The ETH Zurich team collaborated with international research institutions to develop this technology.

• The Institute for Bioengineering of Catalonia (IBEC) and the University of Barcelona contributed to the research.
• Professor Robert Katzschmann leads ETH Zurich’s Soft Robotics Lab, which spearheaded the project.

What they’re saying: Research leaders emphasize the breakthrough nature of this development for biohybrid robotics.

• “This study represents a breakthrough in the development of functional muscle-tendon units, laying the foundation for biohybrid systems that bridge biology and robotics,” explained Professor Katzschmann.
• “We are taking the next major step towards musculoskeletal robots by investigating how to integrate real muscles and tendons into functional units,” he added.
• Lead author Miriam Filippi, a researcher at the Soft Robotics Lab, noted that the team based its solution on “a 3D bioprinted actuator” that “structurally and functionally mimics the natural connection between muscle and bone.”