Experiment of treating dogs' tubular bone fractures in case of mutual usage of biocomposit and lightweight design of the external fixation device
Despite more than half a century time of using external fixation devices, with prototype of Ilizarov's classic device, there is still room for a search for new and original solutions in treatment of animal bone pathology. After analysis of one hundred objects (cadaveric material and clinical cases) of animal limbs, appropriate sizes for production and testing of external fixation device rings were determined. There are 6 sizes for animals from 2-3 kg to dogs up to 50 kg. The material is selected based on the principle of strength and weight parametres. For dogs and cats of small weight up to 2 kg, light materials are used (carbon fiber or titanium alloy, the weight of one ring does not exceed 7 g.) For large animals, rings are made of stainless steel of sufficient thickness. The technological and production solution for manufacture of the set was made by Ulyanovsk branch of Tupolev design bureau under the supervision of its director Stanislav Ryzhakov. For treatment of limb bone fractures of small domestic animals (heterogeneous and of different ages), we used rings from the experimental set of external fixation device with dimensions as close as possible to the anatomical thickness of the limbs of dogs and cats. Application of carbon-plastic fiber in production of rings of the smallest diameter made it possible to reduce the weight of the general structure of the external fixation device by 5-7 times. Intraoperative injection of the LitAr nanostructured hydroxyapatite-collagen material into the fracture site in combination with antibiotics or complex phage preparations made it possible to carry out treatment without possible complications. Mutual use of these two factors resulted in reduction of adherence time of uncomplicated fractures of limb tubular bones 5-7 days earlier than in the control group.