Researching the effects of intramedullary nails which are processed with different hydroxyapatite coating on fracture healing

Fracture is defined as a breach in the anatomic integrity and continuity of the bone resulting from external or internal excessive force. Repair of bone fracture begins as soon as fracture occurs. Healing of fracture has not been clarified accurately yet.Statistics of United States of America (USA) shows that there occurred mean 33 million musculoskeletal injuries per year and 6,2 of these injuries contain various fractures. Although most of these fractures have been treated with conservative methods (splints, plaster detection, various bandages ...etc) surgical interventions are applied for substantial number of those fractures.In the course of detection and selection of the surgical technique, factors such as bone quality, fracture type, anatomic location and surgeons preferences are taken in to consideration.Healing fracture is affected by various factors. Stability is a significant factor in fracture union.Our study aims to compare biomechanical and histological effects of intramedullary nails in different particle size ends coated with hydroxyapatite (HA) porous in healing of experimental fractures of rabbits tibias.For this study, 15 New Zealand rabbits are chosen randomly (n=5) in three groups. Fractures which are formed in mid-diaphysis of left tibias in each subject are treated with intramedullary pin in control group; intramedullary pin end coated with micro size HA is used in MHA group; pin end coated with nano size HA is used for the treatment of NHA group. At the end of the research, biomechanical and histological tests are carried out in disarticulated tibias.Two groups (MHA and NHA) subjected to tensile tests are compared to control group and increase in tensile strength is biomechanically significant increase. As a result of our study, it is determined that intramedullary pins coated with HA shows more significant biomechanical benefit than standard (non-coated) pins.