Mechanical properties of sciatic nerve injury after repaired with poly(lactic acid-glycolic acid) scaffold / 中国组织工程研究

ABSTRACT

BACKGROUND:The tensile and stress-relaxation mechanical properties of sciatic nerve injury after repaired with autologous nerve and poly(lactic acid-glycolic acid) (PLGA) scaffold are rarely reported. OBJECTIVE:To analyze the tensile and stress relaxation characteristics of sciatic nerve injury after the transplantation of autologous nerve and PLGA scaffold. METHODS:Sixty sciatic nerves were extracted from the fresh cadavers dead within 24 hours, processed into 35 mm samples, and were then randomly divided into three groups. The nerve samples in control group received no intervention;the nerves in artificial and autologous groups were modeled into 20 mm defects, followed by repaired with PLGA scaffold and autologous nerve, respectively. Afterwards, the tension and stress-relaxation tests were performed in each group. RESULTS AND CONCLUSION:The stress in each group descended fast at the first 600 seconds, then descended slowly and was closed to the horizontal level until 7200 seconds, and the stress-relaxation curves in each group were in logarithmic decrease. The order of the elastic limit load, elastic limit stress, maximum load, maximum stress, elastic limit strain and maximum strain during tension was as followscontrol group>artificial group>autologous group (P<0.05). Our results indicate that the PLGA scaffold holds good tension and stress-relaxation properties, which meets the mechanical requirements of the biomaterials used for sciatic nerve repair.