tailieunhanh - báo cáo hóa học:" Comparison of transverse wires and half pins in Taylor Spatial Frame: A biomechanical study"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học quốc tế đề tài : Comparison of transverse wires and half pins in Taylor Spatial Frame: A biomechanical study | Khurana et al. Journal of Orthopaedic Surgery and Research 2010 5 23 http content 5 1 23 JOURNAL OF ORTHOPAEDIC SURGERY AND RESEARCH RESEARCH ARTICLE Open Access Comparison of transverse wires and half pins in Taylor Spatial Frame A biomechanical study A A r I I X I I -X 1 T r -X z I fx 0 ir . zx2 T c -X zzx c x x z2t I_11 zzx I -1 x -xlz-x3t xzeilzl_I X I X 1 x x 3 T Asnisn Khurana Carlton Byrne Sam Evans Hiro lanaka Kartik naranaran Abstract Background The aim of this study was to compare the stiffness characteristics of Taylor Spatial Frame TSF fixed with transverse wires and half pins. Design Methods Experiments were carried out at the biomechanics laboratory at Cardiff University. All mechanical testing was performed with a servo hydraulic test frame MTS 858 Mini Bionix II R MTS Corp. Mineapolis USA . Custom built mounts were used to attach the bone rigidly to the one end of machine and the TSF ring to the other. Rings were fixed with mm transverse wires or hydroxy-apatite coated mm half pins in 45degrees 60degrees 75degrees and 90degrees divergence angles. Bone was loaded with axial load to 400 N and torque to 20 Nm in an indestructible manner. Load displacement curve data were analyzed for slope and axial and angular displacements. Results For larger diameter rings 180 mm for axial stiffness there was no statistically significant difference between the transverse wires 4 wires with 2 rings and the half pins 2 pins with 1 ring p . For 155 mm internal diameter rings half pins provided statistically higher axial stiffness than transverse wires p . The half pins show significantly more torsion stiffness in both ring diameters p in comparison to transverse wires. As in axial stiffness small diameter rings show increased stiffness in torsion. There is increase in axial and torsion stiffness with the increase in the divergence angle between the wires or pins p . Conclusion Clinical Relevance Half pins provide greater