ISSN: 2595-7651 Acta Sci Anat. 2019;1(2):141-143.

Sternal foramen in the La Plata dolphin (Pontoporia blainvillei) Fábio A. Rafael1, André Limonge Ráfare2, Marcio Antonio Babinski2, Marcelo Abidu-Figueiredo3

ABSTRACT The sternal foramen is an anatomic variation widely known in humans. It is caused during fetal development and can be commonly found during routine exams or autopsies. It possesses clinical significance as it can lead to misdiagnosis or increase the possibility of pericardial injury during bone marrow biopsy or acupuncture. Being an osseous variation, the sternal foramen can also be found in other mammals, such as cats, calves and dolphins, albeit rarely. We aim to report the presence of the sternal foramen in the sternum of the La Plata dolphin (Pontoporia blainvillei).

Keywords: anatomy, sternum, la plata dolphin, sternal foramen

INTRODUCTION foramen on the caudal portion of sternum (Figure 1). The dolphin sternal foramen observed was single The human skeleton has many variations and oval, situated at the midline of the sternum that may occasionally require distinction from (Figure 1). This anomaly was a complete defect with pathologic changes [1]. The sternum is one of the a denser connective tissue that filled the sternal skeleton parts with most frequent variation on foramen. images appearances or autopsy series [1, 2]. Among them, the sternal foramen is known to be a congenital anomaly represented by a complete perforation of the sternum, usually at its lower end, caused during fetal development [3]. It can be found in other mammals, such cats, calves and dolphins [4-8]. This variation possesses clinical significance in humans due to reports of serious complications after sternal puncture during bone marrow biopsy and acupuncture [4-6]. Thus, studies on the presence and frequency of the sternal foramens were performed in cadavers and dry bones [3, 5], and three-dimensional imaging by helical CT [1, 2]. Figure 1: Photomacrography showing the dry sternum CASE REPORT with a well defined presence of an oval sternal foramen.

.During the preparation and assembly of a dolphin (Pontoporia blainvillei) skeleton in the anatomical laboratory from the Vale do Itajaí University, the specimen showed a complete sternal

1Department of Anatomy, Health Science Center, Vale do Itajaí University, Santa Catarina, Brazil. 2Department of Morphology, Fluminense Federal University, Rio de Janeiro, Brazil. 3Human and Animal Anatomy Department, Federal Rural University of Rio de Janeiro, Rio de Janeiro, Brazil. Corresponding author: Marcelo Abidu-Figueiredo, PhD - [email protected] 142 Sternal foramen in dolphin

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RESUMO Forame esternal no golfinho toninha (Pontoporia blainvillei)

O forame esternal é uma variação anatômica amplamente conhecida em humanos. É causada durante o desenvolvimento fetal e pode ser comumente encontrada durante exames de rotina ou autópsias. Possui significância clínica, pois pode levar a erros de diagnóstico ou aumentar a possibilidade de lesão pericárdica durante a biópsia da medula óssea ou a acupuntura. Sendo uma variação óssea, o forame esternal também pode ser encontrado em outros mamíferos, como gatos, bezerros e golfinhos, embora raramente. Nosso objetivo é relatar a presença do forame esternal no esterno do golfinho toninha (Pontoporia blainvillei).

Palavras-chave: anatomia, esterno, toninha, forame esternal