Muscle
Extensor carpi radialis brevis
Short radial wrist extensor
High-yield
Its tendon crosses wrist compartment 2 with extensor carpi radialis longus. Their insertions differ: brevis reaches metacarpal 3; longus reaches metacarpal 2.
Overview
From the outer elbow, this muscle runs beneath extensor carpi radialis longus to the third metacarpal. It helps hold the wrist extended during gripping.
Reference facts
- Origin
- Common extensor tendon at the humeral lateral epicondyle
- Insertion
- Dorsal base of the third metacarpal
- Action
- Extends the wrist and contributes to radial deviation
- Innervation
- Radial nerve, usually through its deep branch; C7-C8 are commonly listed, and the branching pattern varies
- Blood supply
- Radial and radial recurrent branches, with radial collateral contribution
Clinical correlation
The tendon origin is often involved in lateral elbow tendinopathy, commonly called tennis elbow. This association does not mean that all pain at the outer elbow comes from this tendon.
Frequently asked questions
What does the extensor carpi radialis brevis do?
The extensor carpi radialis brevis extends the wrist and contributes to radial deviation.
What nerve innervates the extensor carpi radialis brevis?
Radial nerve, usually through its deep branch; C7-C8 are commonly listed, and the branching pattern varies.
Where does the extensor carpi radialis brevis attach?
The extensor carpi radialis brevis originates from the common extensor tendon at the humeral lateral epicondyle and inserts on the dorsal base of the third metacarpal.
What is the blood supply of the extensor carpi radialis brevis?
The extensor carpi radialis brevis is supplied by the radial and radial recurrent branches, with radial collateral contribution.