Contribution to the anatomic study of the innervation of the posterior and lateral crico-arytenoid muscles

The complexity of the laringeal inervation has motivated the appearing of a large number of researches, specially that ones related to the recurrent laringeal nerve (RLN). The plentiful variation, the important surgical appliance and even the dificulties in the functional corroboration of the nervous branchs to the larynx make this subject intriguing and challenging. Facing this, the aim of the current study is the elaborated investigation about the recurring laringeal nerve (RLN) branches, directed to posterior (PCA) and lateral (PCL) cricoarytenoid muscles. STUDY DESIGN: Experimental. MATERIAL AND METHOD: It was realized bilateral dissections, on the surgical microscope, in 20 adult's larynxes, from both Sex, referring to posterior and posterolateral regions of the larynx. RESULTS: There are morfological diferences in the RLN's branches that reach the PCA and PCL muscles, observing the unipedicular, bipedicular and tripedicular inervations. There are filaments of PCA muscle arranged obliquely to the main branch, forming "aqueduct", under wich passes the RLN. CONCLUSIONS: The recurring laringeal nerve (RLN) penetrates the larynx beneath its inferior border, behind the cricothyroid joint. The caracteristical inervation of both muscles (PCA and PCL) is predominantly bipedicular; the mentioned "aqueduct", formed by the PCA's fiber bundles, is a anatomical variation not much studied.

larynx; innervation; intrinsic musculature; recurrent laryngeal nerve

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