Abstract:

Objective　To investigate anatomic features of the triceps brachii muscle and its relationships to the radial nerve for improving the exposure of the radial nerve at the postmedian arm.　Methods　31 adult cadavers (62 sides) were dissected. The lateral heads of the triceps brachii muscles were separated bluntly from lateral brachial intermuscular septum　to humerus for exposing the radial nerve. The site where the medial and lateral heads of the triceps brachii muscle merged, the state of two heads before the merge, and the relationship of radial nerve with lateral and medial heads of triceps brachii, were observed and analyzed respectively.　Results　The distance between the site where the radial nerve pierced the lateral brachial intermuscular septum　and the proximal merge point of the medial and lateral heads of the triceps brachii muscle was approximately (6.7±2.6)cm，at the level of olecranon fossa.  Two heads of the triceps brachii muscle separated from each other distinctly. 79% (49 sides) lateral heads wholly arised from the bone surface of humerus proximately to the radial nerve groove, and 21% (13 sides) partly arised from the bone surface of humerus distally to the radial nerve groove, 9 of which were of tendous and 4 muscular types. 　Conclusions　To ulitize anatomic features of the triceps brachii muscle, the exposure of radial nerve at the postmedian arm can be more reasonable and secure.

Key words: Radial nerve,  , Triceps brachii muscle, Applied anatomy