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viscoelastic properties are compared and analyzed, and it is found that the cushion capacity
of the fusion group sample with increased stiffness decreases significantly. Meanwhile, adja-
cent segments of fusion group and spine bear a greater cushion burden.
Loading time of 30 minutes is relatively short compared with many researches on the
viscoelastic properties of IVD (usually the loading time ranges from 4 hours to 8 hours
(Adams et al., 1996)), but for daily load, it is not realistic to continuously sit or stand for
4–8 hours. 30 minutes of continuous load is reasonable, and many experiments adopt load-
ing time of 30 minutes (Wang H. 2014). As for the selection of sample, samples of sheep
spine are very important model in many studies ...