Posterior compartment of the arm
Cross-section through the middle of upper arm.
Latin	compartimentum brachii posterius
Artery	profunda brachii
Nerve	muscular branches of the radial nerve

The posterior compartment of the arm is an anatomic compartment which contains muscles which are all supplied by the radial nerve. This compartment is also known as the "extensor compartment", extension being its main action.

[edit] Contents

The muscles of this compartment are the triceps brachii and anconeus muscle.

• The triceps brachii is a large muscle containing three heads (lateral, medial, and middle).

• The anconeus is a small muscle that stabilizes the elbow joint during movement. Some embryologists consider it as the fourth head of the triceps brachii. As the upper and lower limbs have similar embryological origins and the lower limb contains the quadriceps femoris muscle (the lower limb equivalent of the triceps), which has four heads, this would seem to make sense.

[edit] External links

• lesson4nervesofant&postarm at The Anatomy Lesson by Wesley Norman (Georgetown University)
• Anatomy at Dartmouth elbow/muscles/muscles2
• Anatomy at MUN msk/arm
• Dissection at tufts.edu
• http://anatomy.med.umich.edu/musculoskeletal_system/axilla_ans.html

v • d • e List of muscles of upper limbs (TA A04.6, GA 4.432) Shoulder deltoid · rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) · teres major fascia: Deltoid fascia · Supraspinous fascia · Infraspinous fascia Arm (compartments) Anterior coracobrachialis · biceps brachii · brachialis Posterior triceps brachii · anconeus · Articularis cubiti Fascia Axillary sheath · Axillary fascia · Brachial fascia · intermuscular septa (Lateral, Medial) Other spaces (Quadrangular space, Triangular space, Triangular interval) Forearm Anterior superficial: pronator teres · palmaris longus · flexor carpi radialis · flexor carpi ulnaris · flexor digitorum superficialis deep: pronator quadratus · flexor digitorum profundus · flexor pollicis longus Posterior superficial: mobile wad (brachioradialis, extensor carpi radialis longus and brevis) · extensor digitorum · extensor digiti minimi · extensor carpi ulnaris deep: supinator · anatomical snuff box (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus) · extensor indicis Fascia Bicipital aponeurosis · common tendons (Extensor, Flexor) · Antebrachial fascia Other Cubital tunnel Hand Lateral volar thenar (opponens pollicis, flexor pollicis brevis, abductor pollicis brevis) · adductor pollicis Medial volar hypothenar (opponens digiti minimi, flexor digiti minimi brevis, abductor minimi digiti) · palmaris brevis Intermediate lumbrical · interossei (dorsal, palmar) Fascia posterior: Extensor retinaculum · Extensor expansion anterior: Flexor retinaculum · Palmar aponeurosis

This musculoskeletal system article is a stub. You can help Wikipedia by expanding it. v • d • e