Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học quốc tế đề tài : Biomechanical analysis of a synthetic femoral spiral fracture model: Do end caps improve retrograde flexible intramedullary nail fixation? | Kaiser et al. Journal of Orthopaedic Surgery and Research 2011 6 46 http content 6 1 46 JOURNAL OF ORTHOPAEDIC SURGERY AND RESEARCH RESEARCH ARTICLE Open Access Biomechanical analysis of a synthetic femoral spiral fracture model Do end caps improve retrograde flexible intramedullary nail fixation Martin M Kaiser1 Gregor Zachert2 Robert Wendlandt2 Marion Rapp3 Rebecca Eggert1 Christine Stratmann1 Lucas M Wessel4 Arndt P Schulz2 5 and Benjamin J Kienast5 Abstract Background Elastic Stable intramedullary Nailing ESIN of dislocated diaphyseal femur fractures has become an accepted method for the treatment in children and adolescents with open physis. Studies focused on complications of this technique showed problems regarding stability usually in complex fracture types such as spiral fractures and in older children weighing 40 kg. Biomechanical in vitro testing was performed to evaluate the stability of simulated spiral femoral fractures after retrograde flexible titanium intramedullary nail fixation with and without End caps. Methods Eight synthetic adolescent-size femoral bone models Sawbones with a medullar canal of 10 mm and a spiral fracture of 100 mm length identically sawn by the manufacturer were used for each group. Both groups underwent retrograde fixation with two mm Titanium C-shaped nails inserted from medial and lateral entry portals. In the End Cap group the ends of the nails of the eight specimens were covered with End Caps Synthes Company Oberdorf Switzerland at the distal entry. Results Beside posterior-anterior stress Nm mm vs. Nm mm p the use of End Caps demonstrated no higher stability in 4-point bending compared to the group without End Caps anterior-posterior bending Nm mm vs. Nm mm p medial-lateral bending Nm mm vs. Nm mm p lateral-medial bending Nm mm vs. Nm mm p as well as during internal rotation Nm vs. Nm p . During compression in 9 - .
