AIM: To investigate the in vivo effects of type Ⅰdiabetes on the mechanical strength of tibial bone in a rodent model.METHODS: The biomechanical effect of diabetes on the structural integrity of the tibia in streptoz...AIM: To investigate the in vivo effects of type Ⅰdiabetes on the mechanical strength of tibial bone in a rodent model.METHODS: The biomechanical effect of diabetes on the structural integrity of the tibia in streptozotocin induced diabetic Wistar rats was analysed. Induction of diabetes was achieved by an intra-peritoneal injection and confirmed by measuring serial blood glucose levels(> 150 mg/d L). After 8 wk the tibiae were harvested and compared to a control group. Biomechanical analysis of harvested tibiae was performed using a threepoint bending technique on a servo hydraulic MTS 858 MiniB ionix frame. Maximum force applied to failure(N), stiffness(N × mm) and energy absorbed(N/mm) were recorded and plotted on load displacement curves. A displacement control loading mode of 1 mm/min was selected to simulate quasi-static loading conditions. Measurements from load-displacement curves were directly compared between groups.RESULTS: Fourteen streptozotocin induced diabetic Wistar rats were compared against nineteen non-diabetic controls. An average increase of 155.2 g in body weight was observed in the control group compared with only 5 g in the diabetic group during the experimental study period. Levels of blood glucose increased to 440.25 mg/d L in the diabetic group compared to 116.62 mg/d L in the control group.The biomechanical results demonstrate a highly significant reduction in the maximum load to failure from 69.5 N to 58 N in diabetic group compared to control(P = 0.011). Energy absorption to fracture was reduced from 28.2 N in the control group to 23.5 N in the diabetic group(P = 0.082). No significant differences were observed between the groups for bending stiffness.CONCLUSION: Streptozotocin-induced diabetes in rodents reduces the maximum force and energy absorption to failure of bone, suggesting a predisposition for fracture risk.展开更多
文摘AIM: To investigate the in vivo effects of type Ⅰdiabetes on the mechanical strength of tibial bone in a rodent model.METHODS: The biomechanical effect of diabetes on the structural integrity of the tibia in streptozotocin induced diabetic Wistar rats was analysed. Induction of diabetes was achieved by an intra-peritoneal injection and confirmed by measuring serial blood glucose levels(> 150 mg/d L). After 8 wk the tibiae were harvested and compared to a control group. Biomechanical analysis of harvested tibiae was performed using a threepoint bending technique on a servo hydraulic MTS 858 MiniB ionix frame. Maximum force applied to failure(N), stiffness(N × mm) and energy absorbed(N/mm) were recorded and plotted on load displacement curves. A displacement control loading mode of 1 mm/min was selected to simulate quasi-static loading conditions. Measurements from load-displacement curves were directly compared between groups.RESULTS: Fourteen streptozotocin induced diabetic Wistar rats were compared against nineteen non-diabetic controls. An average increase of 155.2 g in body weight was observed in the control group compared with only 5 g in the diabetic group during the experimental study period. Levels of blood glucose increased to 440.25 mg/d L in the diabetic group compared to 116.62 mg/d L in the control group.The biomechanical results demonstrate a highly significant reduction in the maximum load to failure from 69.5 N to 58 N in diabetic group compared to control(P = 0.011). Energy absorption to fracture was reduced from 28.2 N in the control group to 23.5 N in the diabetic group(P = 0.082). No significant differences were observed between the groups for bending stiffness.CONCLUSION: Streptozotocin-induced diabetes in rodents reduces the maximum force and energy absorption to failure of bone, suggesting a predisposition for fracture risk.
