Experimental Study Of Homograft Of γ-Irradiated Tendon Incorporated With Norfloxacin And Silver

Objective To observe the effect of homograft of γ-Irradiated tendon incorporated with norfloxacin and silver immersion and develop a new homograft tendon processing technique. Methods 32 rabbits were randomly divided into the following four groups: irradiated allogeneic tendon incorporated with norfloxacin and silver group(Group A), irradiated allogeneic tendon group(Group B),deep-frozen allogeneic tendon group(Group C)and autogeneic tendon group(Group D).They were then implanted into defects of Achilles tendons respectively. Ag+ level and bacteriostatic effect were detected in vitro. Biomechanic or histologic properties were observed preoperatively and postoperatilely. Immunologic property and hydroxyproline content were determined postoperatively. Results (1)No bacterial growth was investigated in Group A and B.By contrast,tendons of A group can effectively inhibit growth of bacteria(P<0.01).(2) Before implantation, the ultimate tensile stress of Group A and B was markedly greater than that of Group C and D(P<0.01),but there was no significant difference 12 weeks after operation.(3)Histological findings:At four weeks after transplantation,there were more cells in all grafts than in normal control tendons.The cells of the irradiated grafts were mainly oblong while others were predominatly spindle-shaped or linear. At 12 weeks,cellularity of all grafts had decreased but remained greater than in normal control tendons.The cells were mainly spindle-shaped or linear .(4) The contents of lymphocytoxicity showed lower in Group A,B and D than in Group C(P<0.05).The Hyp level was no significant between Group A ,Band D(P>0.05), but it was lower in Group C(P<0.05).Conclusion γ-Irradiated tendon incorporated with norfloxacin and silver immersion is a good substitute for autogenous grafts,which can remarkably decreased the antigenecity with sterility and strong bacteriostatic effect.