Anatomic and histological analyses of chiasma plantare and long flexor tendons of the foot on human fetuses
The aim of present study was to reveal slip transfers related to flexor hallucis longus (FHL) and flexor digitorum longus (FDL) by dissection and to investigate detailed structure of chiasma plantare composed of FHL–FDL tendons and quadratus plantae (QP), with precise composition of the long flexor tendons of lesser toes by histological sections in human fetuses.
Slip transfers related to FHL and FDL tendons were identified and the related morphometric measurements were taken with dissection in 28 formalin-fixed fetuses (25–40 weeks). Composition and restoration of chiasma plantare and long flexor tendons of lesser toes were traced histological by analyzing movements of the tissues on the sequential coronal sections in five fetuses in the third trimester. The numbers of layers constituting chiasma plantare and the muscles that formed layers were specified. Each of two to five flexor tendons arising from the chiasma plantare was analyzed regarding its formation and contribution of FHL slip.
Slip transfers were found as FHL slip in 86% and cross-connections in 14%. The ratios of the slip width to that of FHL and FDL tendons were found higher than in adult literature. Variance in the involvement of slip to FDL and QP, formation and layering of chiasma plantare and formation of long flexor tendons from chiasma plantare were revealed and great similarities were found with data from dissection of adult in literature.
Slip transfers between FHL and FDL tendons, and layering properties of chiasma plantare were largely finalized during intrauterine period, while structural changes in slip seem to continue in the later stages of life, possibly by the effects of growth and usage of the extremity. In addition to individual variations, investigating the contribution of FHL slip, FDL and QP to long flexor tendons by different methods in literature is also suggested to be responsible for some diversities of our histological study.
KeywordsChiasma plantare Long flexor tendons Flexor hallucis longus Flexor digitorum longus Quadratus plantae Fetus Slip
Ö Elvan: project development, data management, data analysis, manuscript writing, editing. O Beger: project development, data management, data analysis. Mİ Karagül: data management, data analysis, manuscript writing. D Uzmansel: project development, data analysis, editing. NŞ Yılmaz: data management, data analysis, editing. Z Kurtoğlu Olgunus: project development, data analysis, manuscript writing, editing.
Compliance with ethical standards
Conflict of interest
Authors declared no conflict of interest.
- 5.Herring JA (2013) Tachdjian’s pediatric orthopaedics e-book: from the Texas Scottish Rite Hospital for Children. Elsevier Health Sciences, AmsterdamGoogle Scholar
- 9.Kenney WL, Wilmore J, Costill D (2015) Physiology of sport and exercise 6th edition. Human kineticsGoogle Scholar
- 12.Lewis OJ (1962) The comparative morphology of M. flexor accessorius and the associated long flexor tendons. J Anat 96:321–333Google Scholar
- 15.Moore KL, Dalley AF, Agur AMR (2014) Clinically oriented anatomy, 7th edn. Lippincott Williams&Wilkins, BaltimoreGoogle Scholar
- 21.Standring S, Borley NR, Collins P, Crossman AR, Gatzoulis MA, Healy JC (2008) Gray’s anatomy: the anatomical basis of clinical practice, 40th edn. Elsevier, Churchill Livingstone, LondonGoogle Scholar
- 22.Tubbs RS, Shoja MM, Loukas M (2016) Bergman’s comprehensive encyclopedia of human anatomic variation. John Wiley & Sons, New JerseyGoogle Scholar