In vitro virtual reality: an anatomically explicit musculoskeletal simulation powered by in vitro muscle using...

Area of Science:

• Biomechanics
• Muscle Physiology
• Virtual Reality Applications

Background:

• Muscle force-length dynamics are influenced by intrinsic properties, stimulation, and load.
• Existing in vitro methods lack the capacity to integrate limb inertia, musculoskeletal architecture, and contractile dynamics.
• Understanding these combined effects is crucial for advancing muscle physiology research.

Purpose of the Study:

• To introduce and validate an in vitro virtual reality (in vitro-VR) system.
• To enable isolated muscle tissue to actively drive a musculoskeletal simulation.
• To investigate the influence of neuromuscular control and musculoskeletal anatomy on muscle dynamics and biomechanical performance.

Main Methods:

• Developed an in vitro-VR system coupling a frog plantaris muscle to a musculoskeletal jumping simulation.
• Muscle force was transmitted to a software model computing joint torques, inertia, and ground reaction forces at 1 kHz.
• Simulated muscle strain was fed back to update the in vitro muscle length, closing the experimental loop.

Main Results:

• The in vitro-VR system successfully enabled muscle tissue to drive a musculoskeletal simulation.
• Manipulation of stimulation timing and virtual muscle origin altered interactions between muscular, inertial, gravitational, and contact forces.
• Limb kinematics and jump performance were demonstrably influenced by these manipulated parameters.

Conclusions:

• In vitro-VR provides a powerful new tool for studying muscle force-length dynamics.
• This system allows for the investigation of how neuromuscular control and musculoskeletal anatomy interact to dictate biomechanical performance.
• In vitro-VR opens new avenues for understanding complex muscle function in a controlled experimental setting.