Investigating the effects of different constant compression forces on pig femur bone during the process of spiral oblique long bone fracture

Abstract

Spiral Oblique fractures are known to happen by a torsional force while the bone is under certain compression force. The purpose of this research is to compare the effects of two different, constant compressional forces during the process of spiral oblique fracture of pig femur bone. This experiment was performed by simulating the fracture with a Materials Testing System (MTS). An epoxy at both, the proximal and distal heads of the bone stabilized each bone. The bone will then be placed in the MTS. The different tests performed included combinations testing 500 and 750°N compressional forces, each at the 6°, 12°, and 18° per second torsional rate. Seven bones were tested for each of the torque speeds on each group (sample size, n = 7). The average angle of twist for the slow, average, and fast rates for Group 1 were 0.7590°, 0.8948°, 0.9376°, respectively. The average angle of twist for the slow, average, and fast rates for Group 2 were 1.3213°, 1.2580°, 1.7459°, respectively. The average maximum torque for the slow, average, and fast rates for Group 1 were 129.4258°, 133.6292°, 148.4509°, respectively. The average maximum torque for the slow, average, and fast rates for Group 2 were 123.0230°, 113.7802°, 135.7897°, respectively. The average angle of fracture for the slow, average, and fast rates for Group 1 were 64.1919°, 59.9131°, 66.0148°, respectively. The average angle of fracture for the slow, average, and fast rates for Group 2 were 72.9282°, 69.4060°, 71.1549°, respectively. Overall, the fractures made under 750°N were overall cleaner and with higher angles. The proof given by the comparisons between angle of twist, angle of fracture, and maximum torque offer enough evidence that a higher compression force creates an overall cleaner and stronger fracture over the spiral oblique fractures of pig femur bone.