Deltoid muscle innervation in cadaveric specimens: A statistical analysis of the axillary nerve entering sites—preliminary results

Proximal humeral fractures are relatively common in the elderly, especially when osteoporosis is present. Surgical therapy includes deltopectoral and deltoid‐splitting approaches. There was sign of denervation of the axillary nerve, in 12,5% and 25% of the patients when subjected to the deltopectoral and deltoid‐splitting approaches, respectively, even in the absence of clinical symptoms, according to one study. Another study found irreversible increase, as well as histological damage, to the axillary nerve when performing the deltoid‐splitting approach in cadavers specimens. The exact placement of the axillary nerve into the deltoid muscle in not fully comprehended. Our objective in this study is to provide a statiscal analysis for the entry points of the axillary nerve to the deltoid muscle in cadaver specimens, which could possibly have further applications in surgical therapy. The axillary nerve and deltoid muscle were dissected in 5 cadavers, exposing the entry of the axillary nerve into the deltoid muscle. The points where the axillary nerve penetrated the deltoid muscle were collected and transposed to a cartesian graph, divided in 4 quadrants, each one representing a topographic muscular area. Generalized estimation equations were assessed to compare mean points in deltoids with Poisson distribution and identity link function assuming exchangeable correlation matrix. Bonferroni multiple comparisons were used to identify differences between every 2 regions. We have concluded innervation of the deltoid innervation comes predominantly from areas 1 and 3, without significative statistical difference between right and left deltoid muscle or gender. This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .