Researchers at Oregon State University (OSU) have tackled the problem and come up with an implant consisting of a simple pulley system that would more effectively transfer mechanical forces and allow more natural grasping function with less effort.

Unlike the nerve transfer technique we looked at a couple of years ago that reroutes nerves in the upper arms of patients with spinal cord injury at the C7 vertebra to restore some hand function, the technique developed at OSU connects multiple finger tendons to a single muscle via a passive hierarchical artificial pulley system.

This differs from surgical approaches currently used to restore gripping capabilities in hands following nerve damage that involve directly attaching finger tendons to a still-functioning muscle. The downside of such tendon-transfer surgery is that hand function remains significantly impaired, with large amounts of force needing to be exerted and all fingers moving at the same time, rather than separately.