Posterior compartment of the forearm
After completing this study unit you will be able to:
- Name the superficial extensors of the forearm.
- List the deep extensors of the forearm.
- Become familiar with the attachments, innervation and function of each extensor of the forearm.
The muscles of the posterior compartment, also known as the extensor-supinator muscles, are divided into two parts:
- Superficial part: brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi and extensor carpi ulnaris muscles.
- Deep part: supinator, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus and extensor indicis muscles.
Most of the muscles in the superficial layer have a common origin on the lateral epicondyle of the humerus, while the muscles of the deep layer typically originate from the distal part of the ulna. All are innervated by branches of the radial nerve.
Find out more about the origin, insertion, neurovascular supply and function of these muscles by watching the video below.
Take a quiz
After watching the video you should be ready to test and solidify your knowledge of the extensors of the forearm with the following quiz!
If you want a broader focus of questions, customize your own quiz by clicking on the link below.
Download the PDF worksheets and learn the posterior muscles of the forearm.
Examine the extensor muscles of the forearm individually in this gallery.
|Superficial part||Brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor carpi ulnaris and extensor digiti minimi|
|Deep part||Supinator, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus and extensor indicis|
|Innervation||Superficial part: Radial nerve (C5-C8)
Deep part: Posterior interosseous nerve (C7, C8)
|Functions||Mainly extension of hand and digits|