Muscle
Extensor indicis
Independent index extensor
High-yield
Independent extension of the index finger (its tendon lies medial to extensor digitorum's); posterior interosseous nerve.
Overview
A deep extensor giving the index finger its own extensor tendon, allowing pointing. Supplied by the posterior interosseous nerve.
Reference facts
- Origin
- Posterior surface of the ulna and interosseous membrane
- Insertion
- Extensor expansion of the index finger
- Action
- Extends the index finger and assists wrist extension
- Innervation
- Posterior interosseous nerve (C7, C8)
- Blood supply
- Posterior interosseous artery
Frequently asked questions
What does the extensor indicis do?
The extensor indicis extends the index finger and assists wrist extension.
What nerve innervates the extensor indicis?
The extensor indicis is innervated by the posterior interosseous nerve (C7, C8).
Where does the extensor indicis attach?
The extensor indicis originates from the posterior surface of the ulna and interosseous membrane and inserts on the extensor expansion of the index finger.
What is the blood supply of the extensor indicis?
The extensor indicis is supplied by the posterior interosseous artery.