Repeated Freezing And Thawing Of The Biomechanics Of Tendon Allograft People

ObjectiveTo explore the biomechanics effects of multiple freeze-thaw on human allograft tendons.MetrhodsThirty tendons (flexor digitorum superficialis and flexor pollicis longus tendon) were taken from three fresh cadavers. We divided these tendons into six groups randomly (Fresh group;1 cycle,2 cycle,3 cycle,5 cycle or 10 cycle freeze-thaw groups). We estimated structural and mechanical properties as well as viscoelastic change of each group, and performed Statistical comparison of results among groups.ResultsThe results of 1 cycle,2 cycle and 3 cycle freeze-thaw groups were similar to the fresh tendons. The tendons that underwent more than three freeze-thaw cycles demonstrated a significantly lower ultimate load and maximum stress (P<0.05). Moreover, the 5 and 10 cycle groups performed a significant increase in viscoelastic properties compared with other groups.ConclusionIn the cryopreservation of tendon allografts, the cycle of freeze-thaw should not exceed 3 times. Multiple cycle freeze-thaw will weaken the biomechanical properties of tendon allografts, making grafts easier to fatigue or even rupture.