Humeral fracture repair using a robust fixation in an adult Giant Anteater (Myrmecophaga tridactyla): case report

Abstract

The treatment of fractures from the thoracic limb in giant anteaters is extremely challenging. Unfamiliar and peculiar anatomical characteristics, robust musculature and the imminent need for an early return to limb function highlight such challenges. The objective of this report was to describe the successful use of anatomical osteosynthesis with a robust locking compression plate in a humeral fracture of an adult giant anteater. The patient was rescued on the highway after being run over and presented for treatment at the Veterinary Teaching Hospital. Surgical stabilization was performed using a craniomedial approach to the humerus, using a customized broad 3.5mm locking compression plate. The patient presented early limb support at 24 hours postoperatively. Radiographic monitoring was performed at 30, 60 and 90 days postoperatively, and bone healing was observed without any complications. It is concluded that the treatment of humerus fractures in giant anteaters requires robust fixation. The use of a reinforced locking compression plate system proved to be effective and adequate to the mechanical load that an adult individual of this species needs for early use of the thoracic limb and, at the same time, efficient in controlling interfragmentary movement, which allowed fracture consolidation.

An Anatomical Study of the Thoracic Limb of the Giant Anteater (Myrmecophaga Tridactyla) Compared With the Domestic Dog to Guide Surgical Approaches to the Humerus and Radius

“…11 We were able to corroborate this finding, because the approach to the radius in anteaters requires knowledge of the anatomy, which is quite distinct from that of the dog. The medial approach to the radius requires careful dissection of vascular structures, such as the brachial artery, brachial vein, and median nerve, 12 that originate caudal to the humerus and pass through the supracondylar foramen, similar to the anatomical course in cats. 7 Even though careful surgical dissection is required to prevent nerve and vessel injury, the medial approach to the radius is superior to the lateral approach.…”

“…Reports on stabilization of fractures in giant anteaters have used association of implants (double plating) 11,12 increasing the rigidity of fixations. Locked plates do not depend upon friction with the bone, as occurs with dynamic compression bone plating.…”

Surgical stabilization of a distal tibial fracture in a jungle cat (Felis chaus) using orthogonal double plating

“…Surgical procedures in wild animals require special considerations due to important differences in comparison with domestic animals, notably anatomical differences, prolonged bone healing and problems with postoperative management (Minto et al., 2021a, 2021b). These issues have significant implications with regards to treatment and prognosis.…”

“…Treatment of an adult female giant anteater with a mid‐diaphyseal short complete oblique fracture of the left humerus is reported. The fracture was successfully managed with a 3.5 mm broad LCP plate with nine holes, with subsequent resolution of lameness after 90 days (Minto et al., 2021b). Ravasio et al.…”

“…wileyonlinelibrary.com/journal/vms3 1 of 6 https://doi.org/10.1002/vms3.1382 revision of failed plate osteosynthesis (Craig et al, 2018). The application of double plating has been reported previously in other species, such as the polar bear (Zimmerman et al, 2010), giant antlers (Minto et al, 2021a(Minto et al, , 2021b and domestic cats (Voss et al, 2009). Orthogonal plating provides more rigidity during mediolateral bending and a higher failure load in axial compression, although the disadvantage in small bones is the requirement for purchasing more screws (Craig et al, 2018).…”