Morphometric properties of the latissimus dorsi muscle in human fetuses for flap surgery

Although latissimus dorsi (LD) flaps are extensively used in a wide range of interventions, fetus studies on this subject are quite limited. This study aims to obtain detailed information about the morphometric features of LD, thoracodorsal artery (TDA) and nerve (TDN).

The study was carried out on both sides of 50 formalin-fixed human fetuses (22 male/28 female) with a mean gestational age of 24.5 ± 4.7 (range 18-36) weeks, which were in the inventory of Anatomy Department of Mersin University Faculty of Medicine. Dimensions of LD, lengths and width of TDA and TDN were measured. Surface area of LD was calculated using digital image analysis software.

All samples had LD muscle. Neither gender nor side-significant differences were observed in relation with the numerical data of LD, TDN and TDA. Linear function of surface area was calculated as "y = - 1767.532 + 114.582 × Age (weeks)". LD was attached directly to the posterior part of iliac crest in 59 of 100 sides meanwhile in the rest 41, it was attached by the thoracolumbar fascia. TDA gave a branch to serratus anterior in 96 cases and 2 branches in 4 cases. TDN passed superficial to TDA in 84 and deep to TDA in 16 samples. TDN had bifurcation in 93, trifurcation in 6 and tetrafurcation in 1 side.

Data obtained from this study can be useful for estimating the sizes of LD and related neurovascular structures, especially in neonate surgeries. Linear function of LD surface area can be helpful to design the flap dimensions in newborn surgeries. A throughout knowledge about the branching pattern of TDN and its location-wise relation with TDA should be kept in mind to prevent possible complications during harvesting LD flaps and TDN grafts.