Korean J Phys Anthropol.  2018 Sep;31(3):99-103. 10.11637/kjpa.2018.31.3.99.

Concomitant Variations in Flexor Digitorum Superficialis: A Case Report

• Choe WR
• Cho YS
• Nam KI

• KMID: 2429147
• DOI: http://doi.org/10.11637/kjpa.2018.31.3.99

Abstract

The flexor digitorum superficialis (FDS) muscle is located in the intermediate layer of the muscles in the anterior compartment of the forearm. Variable but individual variations have been reported in the FDS regarding the number of head and the origin, distribution and interconnections of muscle slip and insertion to finger. In this case, we report a concomitant complex variation in FDS which was observed in a cadaver during a routine dissection classes for the undergraduate medical students. It includes the variation which is the separation of the tendon of FDS into the superficial and deep layers, the structural variations in muscle slips and associated tendon variations, the finding of Gantzer' muscle leading to flexor pollicis longus muscle. These complex variations in FDS are very rare case and this report summarizes the related phylogenetic and embryological significance.

Keyword

Flexor digitorum superficialis; Variation; Additional muscle; Gantzer' muscle; Additional tendon

MeSH Terms

Cadaver
Fingers
Forearm
Head
Humans
Muscles
Students, Medical
Tendons

Figure

• 

  Fig. 1. Cadaveric dissection showing left flexor digitorum superficialis. Superficial layer (A) and deep layer (B) of left flexor digitorum su-perficialis. SM, superficial-medial muscle slip; SL, superficial-lateral muscle slip; HH, humeral head of superficial-lateral muscle slip; RH, radial head of superficial-lateral muscle slip; MN, median nerve; RN, radial nerve; BR, brachioradialis (cut); DM, deep-medial muscle slip; DL, deep-lateral muscle slip; AM, additional muscle slip; AT, additional tendon; GM, Gantzer's muscle; FPL, flexor pollicis longus.

Reference

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