Morphometric properties of the levator scapulae, rhomboid major, and rhomboid minor in human fetuses.

PURPOSE: The main objective of this study is to showcase the growth dynamics of levator scapulae, rhomboid major, and rhomboid minor algebraically, to help plan surgeries on newborns and young infants.

METHODS: Twenty-five formalin-fixed fetuses (11 male-14 female) with a mean gestational age of 21.80 ± 2.61 (range 18-27) weeks present in the inventory of Mersin University Faculty of Medicine Anatomy Department were dissected. Surface area of levator scapulae, rhomboid major, and rhomboid minor was calculated using digital image analysis software; width and length parameters were measured using digital calipers.

RESULTS: Neither sex nor side significant differences were observed in relation with the numerical data of levator scapulae, rhomboid major, and rhomboid minor (p > 0.05). Algebraic parameters such as surface area, width and length were detected to exhibit a linear growth from 18th to 27th week. Linear functions for levator scapulae, rhomboid major and rhomboid minor surface areas were obtained as y = - 136.871 + 10.598 × age (weeks), y = - 480.567 + 33.147 × age (weeks) and y = - 128.090 + 8.843 × age (weeks), respectively.

CONCLUSION: The results and data of this study can potentially be beneficial in planning of surgeries for many infancy diseases such as trapezius paralysis, obstetrical brachial plexus palsy, Sprengel's disease, or winged scapula. Linear functions calculated in this study are expected to provide a better understanding of the growth dynamics of levator scapulae, rhomboid major, and rhomboid minor in fetal term and more precise estimation of muscle sizes.