Avaliação ex vivo de diferentes designs de fixadores esqueléticos externos com polimetilmetacrilato em modelo experimental de úmero canino.

Abstract

Ex vivo evaluation of different designs of external skeletal fixators with polymethylmethacrylate in an experimental canine humerus model. The aim of this study was to evaluate the different ways of using skeletal fixators from the use of polymethylmethacrylate in order to repair a fracture in an experimental humerus model. Fifteen pieces were used, studying canine humerus bone models, the models were collected in the Laboratory of Animal Pathology of the Veterinary University Hospital Prof. Dr. Ivon Macêdo Tabosa (HVUIMT), Federal University of Campina Grande (UFCG), Patos campus, Paraíba, Brazil. Mice of medium-sized dogs referred for necropsy examinations were dissected, the criterion adopted for inclusion in the study was that of animals between 3 and 5 years of age, of both sexes, without a defined race, without weight restriction and that did not present no endocrine, metabolic, infectious, or any other change that compromises the structure of the appendicular skeleton. care was taken to the collection, dissection and storage of bones, causing minimal changes to the bone models for the test mimetizasse as close to a mechanical test in vivo patient, the same authors also report that this care promote better results. After this process was conducted in a transverse fracture shaft average of all bones with the aid of oscillating saw, at the moment the bone models were divided randomly into three groups of five each bone models: -Group 1 (G1): were prepared FEE system type Ib, with two Schunz pins of 4.5 mm inserted into the cranial level of the bone (a pin for bone fragment) and connected by PMMA and two Schunz pins of the same diameter inserted into the bone side view (a pin for fragment bone) and connected through PMMA. -Group 2 (G2): were prepared FEE system tie-in type with four pins Schunz 4.5 mm inserted into the bone side plane (two pins per bone fragment) and a 4.5 mm intramedullary pin, all the pins were connected with PMMA. -Group 3 (G3): were prepared FEE system of the type tie-in with two Schunz pins inserted into the 4.5mm bone side view (by a pin bone fragment) and a 4.5 mm intramedullary pin, all the pins were connected with PMMA. During the work, it was observed that FEE configurations of type I b have mechanical characteristics similar to Tie-in configurations, being a good alternative to postoperative morbidity o Tie-in, pino, fraturas bserved in patients submitted to Tie-in designs.