Conduit/Wrap Repairs to Digital Nerves Provide Residual Strength After Peak Loading

Area of Science:

• Biomaterials science
• Regenerative medicine
• Microsurgery

Background:

• Sutures are common for digital nerve repair but can damage nerves and fail catastrophically.
• Fibrin glue and nerve conduits support regeneration but lack mechanical strength.
• Maintaining repair integrity after peak load is crucial for guiding nerve regrowth.

Purpose of the Study:

• To evaluate the mechanical strength and integrity of digital nerve repairs using conduits and fibrin glue after reaching peak load.
• To determine if combined techniques offer superior post-peak load performance compared to individual methods.

Main Methods:

• Digital cadaveric nerves were repaired using combinations of epineurial sutures, nerve conduits, and fibrin glue.
• Mechanical testing to failure was performed to assess load capacity.
• Gap displacement and post-peak load energy to dissociation were calculated.

Main Results:

• Conduit with glue and sutures at the ends demonstrated the highest post-peak load energy and displacement.
• Conduit with glue alone showed comparable displacement to repairs with sutures.
• Peak load capacity was similar for conduit-based repairs (with or without glue) and suture-only repairs.

Conclusions:

• Nerve conduits, with or without glue, maintain load capacity and a regeneration pathway post-peak load.
• Suturing at the conduit ends, rather than the coaptation site, minimizes nerve damage.
• Combined use of conduit, glue, and peripheral sutures offers promising mechanical stability for digital nerve repair.