Background: The Brazilian fox (Pseudalopex vetulus, Lund 1842) is a naturally endemic specie of the Brazilian savana vegetation. Due to the rapid destruction of its habitat, the specie is considered “vulnerable” and subject to different kinds of trauma that usually results in fractures and dislocations. Among the methods of fractures fxation, highlights the external skeletal fxator intramedullary pin “tie-in” which consists of the intramedullary pin associated to the external fxator. The aim of the present report was to describe the case of a Brazilian fox with a comminuted tibial fracture, submitted to osteosynthesis using an external skeletal fxator intramedullary pin “tie-in”. Case: It was attended an exemplar of Pseudalopex vetulus, male, young adult, with 3.9 kg body weight and history of functional impotence of the left hindlimb. At the physical and orthopedic evaluations were observed loss of bone continuity and crepitus in tibial region, and the presence of a contaminated lacerating skin wound about 3 cm in diameter in the lateral side of the injured limb. Craniocaudal and mediolateral radiographic projections of the left hindlimb revealed the presence of a complete comminuted fracture at the proximal and distal shaft of the left tibia; and a complete transverse fracture at mid shaft of the left fbula. Due to this, the animal was submitted to fracture fxation using an external skeletal fxator intramedullary pin “tie-in”. For the surgical procedure, broad trichotomy and antisepsis of the left hindlimb were performed, followed by a longitudinal incision on the medial side of the tibia. After bone fragments identifcation, was realized the retrograde positioning of a Steinmann pin of 3.0 mm in diameter toward the proximal epiphysis. Subsequently, the pin was externalized in the parapatelar region and then replaced toward the distal epiphysis. The intramedullary pin was not cut, but folded and attached to the transcortical pins of the unilateral external skeletal fxator using polymethylmethacrylate acrylic resin. For the unilateral external skeletal fxator were placed four Kirschner pin of 1.5 mm in diameter. Of these, two pins were placed at the proximal bone segment of the fracture, and two at the distal one. The central bone segment was not transfxed by pins. Radiographic postoperative examination revealed fracture reduction with good alignment of the bone fragments. The metallic implants were also well positioned. Bone healing was verifed at 150 days postoperatively. At this moment, radiographic examination revealed calcifed and ossifed bone callus, and the maintenance of bone axis.The animal was reintroduced to nature. Discussion: The external skeletal fxator intramedullary pin “tie-in” features biomechanical superiority to both intramedullary and external skeletal fxator pin, since it resists to rotational, bending and axial forces that act at the fracture. Additionally, it is a less expensive fracture fxation method, especially when replacing the lateral connecting rod by polymethylmethacrylate acrylic resin. It was concluded that the external skeletal fxator intramedullary pin “tie-in”can be considered viable in small wild mammals, such as the Brazilian fox (Pseudalopex vetulus), since it enabled the bone healing and the limb functionality. Further studies with a greater number of individuals, however, are necessary to evaluate the real applicability of the fracture fxation method.Keywords: traumatology, osteosynthesis, wild animals.

Background: The giant anteater is considered a species vulnerable to trauma due to being slow and, therefore, vulnerable to long bone fractures, such as femoral fracture. Locking plates have the potential to restore and maintain fractured bone stability, as well as reduce damage to the vascular supply. This study aims at reporting cases of two giant anteaters subjected to femoral osteosynthesis using locking plates. Cases:Two giant anteaters presenting non-weight bearing lameness on the right pelvic limbs were evaluated, diagnosed with femoral fracture of unknown etiology and submitted to osteosynthesis. A clinical evaluation was performed under chemical restraint for the adult animal and physical restraint for the young one. Crepitation and swelling in the right femur topography led to a radiographic examination, which showed a complete and transverse diaphyseal fracture of the right femur in both cases. The first one was an adult male and was subjected to osteosynthesis of the right femur using a locking plate. Once anesthetized, the animal was placed in left lateral recumbency, and the right pelvic limb was clipped and sterilized. A craniolateral incision was made to expose the femoral diaphysis. A large amount of fibrous-looking tissue was found and removed. Subsequently, the fracture was reduced and the locking plate system was positioned on the craniolateral side of the femur. An osteotomy of the femoral trochanteric crest was required to position the implant. The overlying fascia lata was closed using monofilament suture in a simple continuous pattern. The closure of the subcutaneous tissue and skin was performed using a Cushing pattern and simple interrupted pattern, respectively. Immediate postoperative radiographic examinations showed fracture reduction and bone axis alignment, with a properly positioned implant. The surgical wound was cleaned daily with 0.5% aqueous chlorhexidine solution. Seven days after surgery, the animal had a partial dehiscence at the suture site, with bone and plate exposure. Wound healing by second intention was initiated. At 127 days after surgery, a radiographic examination showed periosteal bone proliferation in the middle third of the right femur and that the bone implants were well-positioned. The second case was of a young 3.68 kg female anteater. The surgery was performed as described for the adult one, but there was no fibrosis at the fracture site and the osteotomy of the femoral trochanteric crest was not required. Closure of the fascia lata, subcutaneous tissue, and skin was performed as in Case 1. An immediate postoperative radiographic examination showed fracture reduction, bone axis alignment, and a properly positioned implant. The surgical wound was cleaned daily with 0.5% aqueous chlorhexidine solution. On the day of the surgery, the animal could already bear weight on its right pelvic limb, presenting discrete lameness with gradual improvement. Twenty-three days after surgery, a radiographic examination showed moderate periosteal bone proliferation in the middle third of the right femur. The bone implant was still well-positioned and bone healing was achieved around the 40th post-operative day.Discussion:The cases are very similar, but the younger anteater's femoral trochanteric crest didn't prevent positioning the plate. The fibrosis observed on the adult specimen is indicative of a chronic fracture, which may explain, in conjunction with the post-surgical complications, the longer time required for bone healing in the adult animal. Even so, both animals recovered fully and it's safe to deduce that the locking plate is an adequate option for internal fixation in transverse diaphyseal femoral fractures in both adult and young giant anteaters.