The Musculoaponeurotic System and the Variation in Origin of the Flexor Digitorum Superficialis Muscle

Journal of the Korean Society for Surgery of the Hand 2004;9(4):262-266.
Published online December 1, 2004.

Young Ho Kwon, Pil Jae Park, Young Goo Lee

천수지 굴근 기시부의 근건막 체계와 변이

권영호, 박필재, 이영구

Abstract

Purpose
We studied the variation of relationship between the origin of flexor digitorium superficialis muscle (FDS) and tendons attached to the proximal phalanx in each digit and the anatomy of musculoaponeurotic system of its origin. Materials and Methods: 18 upper extremity cadavers were investigated and the 3-Dimensional anatomy was examined on the origin of FDS. Divided into two group, the independent muscle group was forming the separated origin of FDS. On the other hand, partially or completely mixed muscle fiber of other digit was called the dependent muscle group. Results: The rate of independent/dependent muscle in each origin of FDS was 0/18, 16/2, 8/10 and 0/18 in the order of 2nd to 5th digit. Unusually, intermediate tendon attached to its proximal and distal muscle fiber concurrently was observed in all cases. The origin of FDS showed large surface musculoaponeurotic system and was seen in a fan-shape array. Conclusion: In many cases, FDS was dependent muscle system but relatively independent especially in middle finger. The origin of FDS was formed in 3- Dimensional shape to expand the surface area for its thick muscle origin. Unlike other muscles, FDS had intermediate tendon which did not connect to origin and distal tendon.