Page 208 - Clinical Anatomy

ECA3 7/18/06 6:45 PM Page 193

Course and distribution of nerves 193

Fig. 141◊The distribution
of the radial nerve.

Lying first behind the axillary artery, it then passes backwards between the
long and medial heads of the triceps to lie in the spiral groove on the back of
the humerus between the medial and lateral heads of triceps (Fig. 141). The
profunda branch of the brachial artery and its venae comitantes accompany
the nerve in this part of its course (Fig. 122).
At the lower third of the humerus, the radial nerve pierces the lateral
intermuscular septum to re-enter the anterior compartment of the arm
between brachialis and brachioradialis (a convenient site for surgical expo-
sure, Fig. 137). At the level of the lateral epicondyle its important posterior
interosseous nerve is given off, which winds round the radius within the