Utilização de equipamento de tração esquelética para redução de fraturas de ossos longos em gatos

Abstract

Fractures are frequent orthopedic conditions in the dog and cat clinic. In cats, they comprise approximately 40% of orthopedic cases. When planning a surgical treatment of fracture, the initial decision is to know what type of bone reduction will be performed. Distractors are orthopedic equipment used to reduce fractures, but despite their great application and benefits in human orthopedic surgery, skeletal intraoperative traction through them is not widely used in veterinary medicine. The objective of this study was to evaluate and to use the skeletal traction apparatus made by Tudury et al. (2017) in cats, since there are no reports in the literature of the use of table bone distractors in fracture reduction in this species; as well as to identify particularities for better use in this species, since the bones of these animals are considered more fragile than those of dogs. Before the distractor was used in the fractured cats, a test was performed on seven cadaver bones that showed normal bone densitometry in lumbar vertebra 2 (L2), totaling 14 humers, 14 radios, 14 femurs and 14 tibias. The femur, tibia and humerus bones, with an applied force of 30 kg, did not show macroscopic alterations such as cleft or fracture, at the site of the transfixation of the pins, nor in another region of the same. Already, 100% of the radios tested, fractured in the proximal transfixation hole, with a mean traction force of 24.16kg. Twenty-one fractured cats were operated on, using the distractor in all, being 19 non-defined cats (SRD) and two Siamese cats, aged between six months and two years, and weighing 2.0 kg to 5.3 kg. All fractures were reduced by the open method using indirect and direct reduction techniques. Overall, the mean fracture time was 15 days, the mean traction force applied by the distractor was 4kg and the mean reduction time was 18 minutes. In patients with fracture time greater than seven days, the time used for fracture reduction was higher, being statistically significant (p = 0.021). In some cases, the distractor was removed after performing the bone reduction, as it made it difficult to apply the orthopedic implant and the observation of fracture alignment. Other times, it helped maintain fracture reduction to facilitate the application of orthopedic implants. No fracture / cleft bone was observed in the patient at the site of the distractor, soft tissue, vascular and neurological trans and post surgical injuries due to the use of the distractor. The distractor was efficient in facilitating fracture reduction, also aided in maintaining the reduction and decreased the use of bone tweezers and the force to reduce fracture fragments, thus reducing the risk of fracture of the bone during reduction maneuvers.