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The choice of the thoracic spine fracture fixation needs to recognize the torsional parameters of ribs. In this paper, we carried on the torsional experiment to the normal youth and the old fresh corpse ribs for analyzing their torsional properties and providing the biomechanics parameter in clinic. Forty experimental specimens were taken from 4 normal male fresh corpse, aged 23,27,72,76 years old respectively, and slivered into 55mm long longitudinally, The specimens were divided into 2 groups according to age, each group of 20 specimens. Under the temperature of 20℃, each specimen was nipped to the testing machine and twisted until it was broken at the speed of the 1° per second. When the specimen was broken we captured the maximums of torque and torsion angle via the test machine, observed the macroscopic fracture appearance of each specimen. The shear stress of each specimen was following calculated as well. The experimental results proved that the maximum torque, shear stress and torsion angle of youth rib were greater than those of the old with significant differences (P<0.05), which means there is difference in torsion property between youth and the old. By macroscopic observation we found that the most of fractured surfaces showed slanting and less horizontal, the bone trabecula of youth rib arranged closely, the old’s arranged sparsely, which are some features of senile osteoporosis.