Morphology of the brain base arteries of the giant anteater (Myrmecophaga tridactyla)

This study aimed to describe the brain base arteries of the Myrmecophaga tridactyla using ten cadavers of adults from this species, including five male and five female specimens. The arterial vascular bed was perfused via the thoracic aorta with a dyed natural latex solution, and the animals were fixed and preserved with a 10% formaldehyde buffered solution. The encephala were removed, and their vessels dissected. Basilar artery formation occurred by anastomosis of the thick ventral spinal artery with vertebral arteries. The basilar artery formed two arterial islands and gave bulbar and pontine branches, and cranial, middle, and caudal cerebellar arteries and ended by forking into its terminal branches, the caudal communicating arteries. The blood supply of the encephalon derived solely from the vertebrobasilar system, and the arterial circle of the brain was closed caudally and rostrally. The absence of participation of internal carotid arteries in encephalon irrigation, the island formations by the basilar artery, and the fusiform shape of the arterial circle of the brain are peculiar characteristics of the vascular anatomy of the brain base of M. tridactyla.

Reparo de lesão vascular não letal causada por tamanduá-bandeira (Myrmecophaga tridactyla) no Brasil / Repair of non-lethal vascular injury caused by giant anteater (Myrmecophaga tridactyla) in Brazil

Resumo O tamanduá-bandeira é um mamífero encontrado na América Central e na América do Sul. Esse animal possui garras que podem chegar a 6,5 cm de comprimento, utilizadas para escavar formigueiros e obter alimento, além de servir para sua defesa. Relatamos o caso de paciente masculino de 52 anos, com histórico de epilepsia, que foi levado desacordado ao pronto-socorro, devido a lesões no seu braço direito causadas por um tamanduá. Frente à suspeita de trauma vascular, o paciente foi submetido a exploração cirúrgica, que evidenciou uma lesão combinada de vasos braquiais, submetida a reparo. Apresentou boa evolução do quadro, recebendo alta hospitalar no segundo dia de pós-operatório e, no seguimento ambulatorial, evoluiu sem sequelas neurológicas ou vasculares.

Abstract The giant anteater is a mammal found in Central and South America. These animals have claws that can reach 6.5 centimeters in length, which they use to dig anthills to obtain food and for defense. We report the case of a 52-year-old male patient with a history of epilepsy who was taken unconscious to the emergency room due to injuries to his right arm caused by an anteater. He underwent surgical exploration to investigate suspected vascular trauma, revealing a combined (arterial and venous) injury of the brachial vessels, which were repaired. He recovered well and was discharged on the second postoperative day. During outpatient follow-up he continued to improve, with no neurological or vascular sequelae.

Anátomo-radiografia dos ossos longos do membro torácico do Tamandua tetradactyla / Anatomo-radiography of long-bones in thoracic limb of Tamandua tetradactyla

Objetivou-se descrever os acidentes anatômicos dos ossos longos do membro torácico de Tamandua tetradactyla por meio de análises macroscópicas e radiográficas. Foram utilizados 34 espécimes, que foram a óbito por atropelamento. A avaliação do úmero demonstrou as mesmas estruturas presentes nos animais domésticos, além de outras sem prévia descrição. Já no antebraço, rádio e ulna se apresentaram completamente separados, e apesar de, como o úmero, serem identificados alguns dos mesmos acidentes anatômicos descritos em outras espécies, também notamos particularidades. Todas as estruturas descritas na análise macroscópica foram identificadas à radiografia, quando realizada em pelo menos duas projeções ortogonais. As estruturas anátomo-radiográficas dos ossos longos do T. tetradactyla demonstraram grande variaçãoanatômica em comparação a outros mamíferos, o que torna a referida espécie muito singular. Assim o conhecimento de suas particularidades é fundamental para abordagens clínico-cirúrgicas mais seguras.

The objective was to describe the anatomical accidents of the long bones of the thoracic limb of Tamandua tetradactyla by means of macroscopic and radiographic analyzes. We used 34 specimens, which were death by running over. Evaluation of the humerus demonstrated the same structures present in domestic animals, besides others without previous description. In the forearm, radius and ulna were completely separated, and although, like the humerus, some of the same anatomical accidents described in other species were identified, we also noticed particularities. All the structures described in the macroscopic analysis were identified on radiography, when performed in at least two orthogonal projections. The anatomic-radiographic structures of the long bones of T. tetradactyla showed great anatomical variation compared to other mammals, which makes the species very unique. Thus knowledge of their particularities is fundamental for safer clinical-surgical approaches.