Definition

By: Gregory R. Waryasz, MD

The brachioradialis muscle of the musculoskeletal system is characterized by being the only posterior/extensor compartment of the forearm muscle that flexes the elbow.

It is part of the forearm.  It consists of skeletal muscle fibers.

Its unique structural features include its fusiform shape. It helps to form the lateral border of the cubital fossa.

The origin is the proximal two-thirds of the supraepicondylar ridge of the humerus

The insertion is the lateral surface of the distal end of the radius proximal to the styloid process.

The blood supply is from the radial recurrent  artery and venous drainage is from the accompanying veins.

The innervation is from the radial nerve.

The brachioradialis muscle as well as all other bones, muscles, and ligaments of the body are derived of mesodermal origin in the embryo.

The function of the brachioradialis is to flex the elbow. It also is a semipronator and a semisupinator. During quick movements or when there is resistance to forearm flexion, the brachioradialis muscle helps to resist subluxation of the radial head. The synergists are the brachialis and the biceps brachii.

There are no common diseases.

Commonly used diagnostic procedures include clinical history, physical exam, and MRI.

References

Lieberman J (ed), AAOS Comprehensive Orthopaedic Review, American Academy of Orthopaedic Surgeons, 2008.

Moore K, Dalley A (eds), Clinically Oriented Anatomy (5th edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.

Wheeless’ Textbook of Orthopaedics: Brachioradialis (http://www.wheelessonline.com/ortho/brachioradialis)