Anat Cell Biol.  2019 Mar;52(1):97-99. 10.5115/acb.2019.52.1.97.

A rare bilateral variation on the dorsum of the hand: extensor digitorum brevis manus and extensor medii proprius

• Lee DH
• Lee JH
• Woo RS
• Song DY
• Baik TK
• Yoo HI

• KMID: 2442338
• DOI: http://doi.org/10.5115/acb.2019.52.1.97

Abstract

A 78-year-old male cadaver showed bilateral anomalous muscles on the dorsum of the hand. An extensor digitorum brevis manus was noted on the dorsum of the right hand. It originated from the distal end of the radius and the radiocarpal joint ligaments and inserted into the metacarpophalangeal joint of the third digit. On the dorsum of the left hand, an extensor digiti medii proprius was identified. It originated from the distal third of the ulna near the extensor indicis proprius and the interosseous membrane and inserted into the metacarpophalangeal joint of the third digit. Awareness of these combined muscular variation would be helpful in understanding the identification of digital extensors and in requiring careful consideration for the reconstruction surgery of the hand.

Keyword

Forearm; Hand; Extensor digitorum brevis manus; Extensor medii proprius

MeSH Terms

Aged
Cadaver
Forearm
Hand*
Humans
Joints
Ligaments
Male
Membranes
Metacarpophalangeal Joint
Muscles
Radius
Ulna

Figure

• 

  Fig. 1 (A, B) Digital photograph and a sketch show the origin and insertion of the extensor digitorum minimi (EDBM) on the dorsum of the right hand. APL, abductor pollicis longus; DBUN, dorsal branch of the ulnar nerve; ED, extensor digitorum; EDM, extensor digitorum minimi; EIP, extensor indicis proprius; EPB, extensor pollicis brevis; EPL, extensor pollicis longus.

• 

  Fig. 2 (A, B) Digital photograph and a sketch show the origin and insertion of the extensor medii proprius (EMP) on the dorsum of the left hand. APL, abductor pollicis longus; DBUN, dorsal branch of the ulnar nerve; ED, extensor digitorum; EDM, extensor digitorum minimi; EIP, extensor indicis proprius; EPB, extensor pollicis brevis; EPL, extensor pollicis longus.

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