Torsional strenght of graft removed long bones

Halit Ozyalcin, Erhan Sesli, Unal Evcim, Gurbuz Celebi,


It s important to know decreasing the torsional strength of graft removed bones which is frequently use for bone grafting. In this experimental and biomechanial research it is animed determining the maximum torqua force and energy to find the maximum area and shape of graft in secur limits. Circular and rectangular cortical grafts were removed from the right tibiae of 80 pairs of sheep bones. The area of the grafts were one cm2 and one and half cm2 Each pairs were broken comparingly by applying torque force. Sudden and strong torsional fractures were preferred because loading configuration effects to every section alongs its length and similar is encountered in clinical fraclures. \nIn experiment, the standard test machine of Burstein and Frankel s principles were used. The curve of maximum torque and degree for the fractures were obtained electronically and the results were digitalised by the computer. Torsional strength of the bones were compared with the contralateral samples. Average torsional strength loss are 11.28 (Nm) (%51.5) and 12.65 (Nm) (%60.2) for rectangular graft, removing with one, and one and half square centimeters. Subsequently, the values of 4.51 (Nm) (%19.66) and 4.71 (Nm) (%20.96) are measured as an average differences for the circular shape grafts removing with the same areas. The decrease of strength less in circular grafts.

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