The anconeus is one of the muscles of the superficial layer of the posterior compartment of the forearm. It is a small triangular muscle just posterior to the elbow joint, its muscle fibres partially blend with the triceps brachii muscle.
The posterior compartment of the forearm consists of a superficial layer (7 muscles) and a deep layer (5 muscles).
The muscles in the superficial layer include:
- Brachioradialis
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor digitorum
- Extensor digiti minimi
- Extensor carpi ulnaris
- Anconeus
The muscles of the superficial layer share a common origin from the lateral epicondyle and lateral supracondylar ridge of the humerus.
All the muscles of the posterior compartment are innervated by the radial nerve.
Origin
- Lateral epicondyle of the humerus
Insertion
- Lateral surface of olecranon and proximal posterior surface of the ulna
Action
- Assists in extension
- Stabilises the elbow during pronation and supination
- Pulls the slack out of the elbow joint capsule which prevents it being pinched during extension
Innervation
- Radial nerve
Blood Supply
- Interosseus recurrent artery (from the posterior interosseus artery)