Extensor carpi ulnaris muscle
Citation, DOI, disclosures and article data
Citation:
Mirt G, Bell D, Hacking C, et al. Extensor carpi ulnaris muscle. Reference article, Radiopaedia.org (Accessed on 15 Mar 2025) https://doi.org/10.53347/rID-39872
rID:
39872
Article created:
24 Sep 2015,
Greg Mirt
Disclosures:
At the time the article was created Greg Mirt had no recorded disclosures.
View Greg Mirt's current disclosures
Last revised:
Disclosures:
At the time the article was last revised Daniel J Bell had no recorded disclosures.
View Daniel J Bell's current disclosures
Revisions:
15 times, by
8 contributors -
see full revision history and disclosures
Systems:
Sections:
Synonyms:
- Extensor carpi ulnaris tendon
- Extensor carpi ulnaris (ECU) muscles
- Extensor carpi ulnaris muscle
- Extensor carpi ulnaris (ECU) muscle
Extensor carpi ulnaris (ECU) muscle is a muscle of the superficial layer of the posterior compartment of the forearm. It is separated from the extensor digitorum and the extensor digiti minimi muscles by a distinct intermuscular septum. It is the only forearm extensor that lies in its own fibro-osseous tunnel at the level of the wrist with its own subsheath as it passes through the 6th extensor compartment of the wrist. At the level of the ulna, it is covered by a subsheath, extensor retinaculum and the linea jugata. It is one of the extrinsic muscles of the hand.
Summary
- origin: lateral epicondyle of humerus, radial collateral ligament and posterior border of ulna
- insertion: base of 5th metacarpal on posterior surface
- arterial supply: radial recurrent artery and posterior interosseous artery
- innervation: posterior interosseous nerve (C7 and C8), a continuation of the deep branch of the radial nerve (C7, C8)
- action: extension and adduction (i.e. ulnar deviation) of the wrist joint
Related pathology
- tendinosis and/or tenosynovitis
- ECU is the second most common site of upper limb tenosynovitis 3
- subluxation of the ECU tendon with subsheath injury 3
References
- 1. Last's anatomy, regional and applied. Churchill Livingstone. ISBN:044304662X. Read it at Google Books - Find it at Amazon
- 2. Standring, Susan, and Henry Gray. 2008. Gray's anatomy: the anatomical basis of clinical practice. [Edinburgh]: Churchill Livingstone/Elsevier. http://www.clinicalkey.com/dura/browse/bookChapter/3-s2.0-B9780443066849X5001X
- 3. Plotkin B, Sampath SC, Sampath SC, Motamedi K. MR Imaging and US of the Wrist Tendons. (2016) Radiographics : a review publication of the Radiological Society of North America, Inc. 36 (6): 1688-1700. doi:10.1148/rg.2016160014 - Pubmed
Incoming Links
Articles:
- Wrist
- Posterior interosseous nerve
- Ultrasound of the wrist
- Triquetrohamate ligament
- Tenosynovitis
- Reverse Bennett fracture-dislocation
- Ulnar collateral ligament of the wrist
- Posterior compartment of the forearm
- Rheumatoid arthritis (musculoskeletal manifestations)
- Extrinsic muscles of the hand
- Extensor carpi ulnaris tendinopathy
- Ulna
- Radiocarpal joint
- Ulnomeniscal homologue
- Extensor compartments of the wrist
- Tendon instability
- Accessory flexor carpi ulnaris muscle
- Common extensor origin of the elbow
- Antebrachial fascia
- Galeazzi fracture-dislocation
Cases:
- Extensor carpi ulnaris stenosing tenosynovitis
- Foreign body - extensor carpi ulnaris tendon sheath
- Scaphoid nonunion with humpback deformity
- Extensor carpi ulnaris subluxation
- Traumatic extensor carpi ulnaris subsheath injury and subluxation
- Wrist extensor tendons (reporting aid)
- Triangular fibrocartilage complex injury - Palmer 1a
- Extensor carpi ulnaris tendon split tear
- Extensor carpi ulnaris tendinosis
- Physeal arrest of the distal radius with midcarpal instability
- Extensor carpi ulnaris tendinosis and tenosynovitis
- Distal radio-ulnar joint subluxation
- Extensor carpi ulnaris subluxation
- Extensor carpi ulnaris subluxation
- Extensor carpi ulnaris tendinopathy and tenosynovitis
- Extensor carpi ulnaris tendinopathy
- Extensor carpi ulnaris tenosynovitis
- Extensor carpi ulnaris tendinosis and tenosynovitis
- Extensor carpi ulnaris tenosynovitis
- Extensor carpi ulnaris tendinosis and tenosynovitis
Multiple choice questions:
Related articles: Anatomy: Upper limb
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skeleton of the upper limb
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- scapula
- humerus
- radius
- ulna
- hand
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- accessory ossicles of the shoulder
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accessory ossicles of the wrist (mnemonic)
- os centrale carpi
- os epilunate
- os epitriquetrum
- os styloideum
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pectoral girdle
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shoulder joint
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glenohumeral joint
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shoulder joint
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wrist joint
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ligaments
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- radioscaphoid ligament
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- dorsal radioulnar ligament
- volar radioulnar ligament
- radioscaphocapitate ligament
- long radiolunate ligament
- Vickers ligament
- short radiolunate ligament
- ulnolunate ligament
- ulnotriquetral ligament
- ulnocapitate ligament
- ulnar collateral ligament
- associated structures
- extensor retinaculum
- flexor retinaculum
- joint capsule
- movements
- alignment
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hand joints
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metacarpophalangeal joints
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interphalangeal joints
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pectoral girdle
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anterior compartment of the forearm
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posterior compartment of the forearm (extensors)
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accessory muscles
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arteries
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arteries
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brachial plexus (mnemonic)
- branches from the roots
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- branches from the cords
- lateral cord
- posterior cord
- medial cord
- terminal branches
- lymphatic drainage of the upper limb