Abstract: Ｏｂｊｅｃｔｉｖｅ：To investigate the bone biomechanical features of femur and the fifth lumbar vertebra in an adenineinduced renal osteodystrophy rat model of chronic kidney disease (CKD).Ｍｅｔｈｏｄｏｌｏｇｙ：Twenty male Sprague Dawley rats of eleven weeks old were divided into two groups:(1)  normal group,which were fed a diet without adenine;  (2)  CKD group,which were fed an 075％ adenine diet for the initial 4 weeks and then adeninefree diet for the subsequent 2 weeks.Six weeks later,rats were subjected to euthanasia and serum was collected for biochemical marker tests.Bone mineral density (BMD) and bone biomechanical parameters were examined in femurs and the fifth lumbar vertebra.
Ｒｅｓｕｌｔｓ： At the end of the sixth week,serum creatinine,blood urea nitrogen,serum phosphorus and serum parathyroid hormone were significantly higher,and serum calcium was significantly lower,in the CKD group compared with the normal group.Total femur BMD and fifth lumbar vertebra BMD were lower significantly in CKD group than in normal group.For bone biomechanical tests,femur threepoint bending tests indicated the femur indexes of both structural mechanics (maximum load,maximum displacement,stiffness,force energy) and materials mechanics (maximum stress,maximum strain,elastic modulus,toughness) in CKD group decreased significantly than in normal group,and lumbar compression tests indicated the fifth lumbar centrum indicators of both structural mechanics (maximum load,maximum displacement,stiffness,force energy) and materials mechanics (maximum stress,maximum strain,elastic modulus,toughness) in CKD group decreased significantly than in the normal group.Ｃｏｎｃｌｕｓｉｏｎ： Adenineinduced rat renal osteodystrophy model of CKD showed deteriorated properties of structural mechanics and materials mechanics in both cortical and trabecular bone,these features were in accordance with the actual clinical conditions.This model could be an appropriate medium in the study of  renal osteodystrophy in CKD in the future.