Caratterizzazione biomeccanica sperimentale di tecniche di osteosintesi

Introduction:Locking plates (LP) and screws for distal radius and proximal humerus fractures are two conventional surgical approaches to 4-fragments fractures fixation. Malunion of fragments in osteoporotic patients treated with locking plates, associated with loss of fracture reduction, and screw cut-out/migration are the common complications of the use of LP and screws. Cement augmentation seems improve the outcome of the fracture recostruction. Aim: The aim of this study was to compare the biomechanical characteristics of three different techniques for the reconstruction of a specific type of fracture of the distal radius and proximal humerus. Hypothesis:A bone substitute was used in combination or in replacement of plates and screws. It featured similar mechanical properties to metallic plates, representing a possible alternative Methods: Twelve pairs of radii were divided into two groups (Group A & B). In the first group six radii were treated with gold standard and the controlateral radii with the first innovative technique. In the group B the controlateral radii were treated with the second innovative technique. Six pairs of humeri were included in a third group. Six humeri were treated with gold standard technique, and the controlateral humeri were reconstructed with the second innovative technique Results:All specimens of human radii showed a typical failure. In the groups A and B the forces and an initial slope of Cement-and-Screws was on average larger than controlateral Screws-Only. All specimens of human humeri showed a progressive failure which started at 1st force failure just below the maximum force. The 1st failure e maximum forces of the Cement-Only was on average larger than the controlateral Screws-Only Conclusions:The two Innovative reconstructions showed positive results, demonstrating better mechanical characteristics compared to the Standard reconstructions. For humeri the results are definitive, while radii’s study requires further tests.