Upper limb

Brachioradialis

Musculus brachioradialis

Origin

Proximal two-thirds of the lateral supracondylar ridge of the humerus

Insertion

Lateral side of the distal end of the radius, near the styloid process of the radius

Function

Flexion of the elbow, most powerful in the mid-position between pronation and supination

Innervation

Radial nerve

Movement & chain

Acts as an 'emergency brake' during rapid elbow flexion movements and actively brings the forearm to the neutral (thumb-up) position from both pronation and supination.

Palpation

Clearly visible and palpable as the most lateral muscle belly of the forearm, directly distal to the elbow crease, during flexion against resistance in the mid-position.

Clinical

May be involved in radial tunnel syndrome, in which the radial nerve can become entrapped beneath the muscle.

Segmental innervation

Radial nerve, C5-C6.

In clinical practice

The brachioradialis reflex (radial periosteal reflex) is elicited here by tapping the distal muscle belly or tendon and is a standard part of the neurological examination of the C5-C6 segments.

Region in the model

Upper limb