Muscular Branch of Radial Nerve to Brachioradialis (Left)

Origin

A motor nerve branch to brachioradialis muscle originates from the radial nerve and contains motor nerve fibers from the C5—C6 cervical spinal segments.

Course

In the upper part of the arm, it descends posterolaterally (with the profunda brachii vessels) through the lower triangular space, between the shaft of the humerus, long head of triceps brachii, and teres major muscles. The nerve then enters the radial groove along with the profunda brachii vessels. It descends downwards and laterally between the lateral and medial heads of the triceps muscle, while in contact with the humerus.

In the lower part of the arm, it pierces the lateral intermuscular septum and passes into the anterior compartment of the arm to reach the cubital fossa where it lies between the brachialis muscle medially and brachioradialis and extensor carpi radialis longus muscles laterally. The radial nerve then passes deep to the brachioradialis muscle in the posterior compartment of the forearm and gives off a branch to the muscle before splitting into its superficial and deep terminal branches.

Branches

There are no named branches.

Supplied Structures

The muscular branch of the radial nerve to brachioradialis provides motor innervation to the brachioradialis muscle.

List of Clinical Correlates

—Inverted brachioradialis (inverted supinator) reflex (McGee, 2016)

References

McGee, S. (2016) Evidence-Based Physical Diagnosis E-Book. Elsevier Health Sciences.