The irradiation effect on the initial mechanical properties of meniscal grafts.

In this study, the effect of sterilization was investigated on the mechanical properties of rabbit's meniscal grafts. The processes of freezing and irradiation were carried out and their effects upon the elastic and viscoelastic properties measured using a tensile testing machine and an indentation test. It was found that gamma irradiation, at dosages commonly used for sterilizing grafts, had a significant adverse influence on the elastic and viscous response of the grafts. Freezing led also to a small significant decrease in elastic stiffness but no change in failure strength. It is concluded that irradiation sterilization is unsuitable for clinical use and other techniques should be used whenever possible.