Topography of the medullary cone of Choloepus didactylus for locoregional anesthesia purposes.

Choloepus didactylus (two-toed sloth) is a Xenarthran mammal whose morphology has so far been little studied. Given the increasing number of sloths requiring clinical and surgical interventions, this lack of clarity regarding anatomical features and landmarks has had a negative impact on veterinary decision-making for this species. We therefore sought to describe the topography of the medullary cone (MC) of Choloepus didactylus in order to provide guidance to qualified professionals on the ideal access for locoregional anesthesia. In evaluating four specimens, radiographs and dissections revealed that Choloepus didactylus has three lumbar vertebrae and five sacral vertebrae. The lumbar intumescence is located between T14 and the cranial half of L2, the medullary cone is located between the caudal half of L2 and L3, with an average length of 2.26 cm, and the cauda equina extends from S1 to S5. Based on these anatomical findings, we propose that the lumbosacral region would be the most suitable target for epidural anesthesia in Choloepus didactylus.