3D Reconstruction of the Blood Supply in an Elephant’s Forefoot Using Fused CT and MRI Sequences

Abstract

Being the largest still-living terrestrial mammal on earth, an elephant’s feet play an important role in its health status. The musculoskeletal structures in the forefoot are well described in the literature, but information about vascularization is limited. The novel aim of this work is to provide anatomical guidance to structures found in the forefoot, focusing on the arterial system. Initially, native CT and MRI sequences were taken of the left forefoot of a deceased 6-year-old female Asian elephant; the foot was then filled with an iodine-containing contrast medium through the a. mediana and the CT scans were repeated in the same position. The images obtained were processed with 3D Slicer software for the 3D reconstruction of the bones and arteries. The results clearly showed the palmar blood supply of the forefoot. A so far undescribed vessel was revealed, stemming from the a. metacarpea, supplying the first digit and the digital cushion. The course of the deep palmar arch’s terminal section was also established. This paper provides the first description of the exact disposition of the arteries in the palmar aspect of an elephant’s forefoot and may be used in planning surgeries in clinically affected animals.

CT reconstruction based 3D model of the digital cushion’s blood supply in the hind foot of an African savanna elephant (Loxodonta africana)

“…Our study is the first to report the sinus tarsi in an African elephant. Although previously unreported in this species, it is in line with the anatomy of domestic mammals (20,21) and the Asian elephant (25).…”

“…Ramsey & Henry did not report the division on the proximal portion of both the medial and the lateral plantar arteries or the anastomoses near the sole, indicating that their dissection stopped at the level of the tarsus ( 17 ). This setup is very different from the one described in the forelimb of the Asian elephant ( 25 ), where a single trunk arising from the arcus palmaris profundus would serve as the major vessel, and its direct branches reach the digital cushion close to the median plane of the limb. Previous studies state that the anatomy of the hindfoot in the different elephant species are similar ( 17 , 18 ).…”

“…This study is subject to certain limitations, mainly the utilization of only one specimen for the research. Anatomical studies of rare, endangered species often use only one (25,(39)(40)(41)(42) or two (43) subjects. In addition, the possibility to use imaging techniques such as CT and MRI are also limited by the size, weight, and transport issues of this species (16) and the cost of such examinations.…”

“…Petneházy et al described the blood supply of the digital cushion in the forelimb of an Asian elephant using computed tomography (CT)-based reconstruction ( 25 ). They found that the metacarpal artery gave rise to a short trunk, which divided into a palmar and a dorsal branch, both of which supply the digital cushion from their respective directions; the short trunk also gave off a branch running toward the first digit.…”