Anatomical aspects of the nerves of the leg and foot of the giant anteater (Myrmecophaga tridactyla, Linnaeus, 1758)

Although distal stifle joint nerve distribution has been well established in domestic animals, this approach is scarcely reported in wild animals. Therefore, the aim of this study was to describe the nerves of the leg and foot of Myrmecophaga tridactyla with emphasis on their ramification, distribution, topography and territory of innervation. For this purpose, six adult cadavers fixed and preserved in 10% formalin solution were used. The nerves of the leg and foot of the M. tridactylawere the saphenous nerve (femoral nerve branch), fibular and tibial nerves and lateral sural cutaneous nerve (branches of the sciatic nerve) and caudal sural cutaneous nerve (tibial nerve branch). The saphenous nerve branches to the skin, the craniomedial surface of the leg, the medial surface of the tarsal and metatarsal regions and the dorsomedial surface of the digits I and II (100% of cases), III (50% of cases) and IV (25% of cases). The lateral sural cutaneous nerve innervates the skin of the craniolateral region of the knee and leg. The fibular nerve innervates the flexor and extensor muscles of the tarsal region of the digits and skin of the craniolateral surface of the leg and dorsolateral surface of the foot. The tibial nerve innervates the extensor muscles of the tarsal joint and flexor, adductor and abductor muscles of the digits and the skin of the plantar surface. The caudal sural cutaneous nerve innervates the skin of the caudal surface of the leg. The nerves responsible for the leg and foot innervation were the same as reported in domestic and wild animals, but with some differences, such as the more distal division of the common fibular nerve, the absence of dorsal metatarsal branches of the deep fibular nerve and a greater involvement of the saphenous nerve in the digital innervation with branches to the digits III and IV, in addition to digits I and II. Apesar de bem estabelecida nos animais domésticos, a abordagem da distribuição nervosa distal do joelho é rara em animais selvagens. Portanto, o objetivo deste estudo foi descrever os nervos da perna e pé do Myrmecophaga tridactyla, com ênfase na sua ramificação, distribuição, topografia e território de inervação. Para tanto, foram utilizados seis cadáveres adultos, fixados e conservados em solução de formalina a 10%. A dissecação envolveu desde a formação dos nervos femoral e isquiático pelos ramos ventrais dos nervos espinhais lombares e sacrais até sua distribuição nos territórios propostos. Os nervos resp