Mechanical properties of the human brachial plexus.

This study shows measurements of force and elongation during experimental traction of human brachial plexus. Experiments were realised on fresh cadaveric specimens, mechanism of traction injury of brachial plexus was simulated. Predominant lesion provoked by direct lateral traction of isolated brachial plexus was avulsion of the roots. Epineural mechanical failure as first lesion occurred at anterior margin of avulsed roots in the proximity of intervertebral foramen. The force leading to rupture of brachial plexus ranged between 217.7N-546.3N, stress value between 1.3 N/mm2-3.5 N/mm2. Elongation until rupture was 19.6%-58.8% of initial length.