Animal Experimental Study On The Effect Of Diabetes Mellitus On Bone Ingrowth Of Titanium Screw

Objectives:To provide experimental basis for perioperative strategies of artificial joint replacement in clinical DM patients through the comparative observation of the effect of diabetes mellitus on bone ingrowth of titanium screw.Methods:We purchased sixty healthy SD male rats aged 2 months and weighing 200~230g.Then the rats are randomly divided into two groups with 30 rats in each group,the diabetic group and the normal control group.Diabetic rats are intraperitoneally injected with 1% streptozocin(STZ)to estabilish a diabetic animal model,and blood glucose is monitored to comfirm the success of the diabetic rat model.After 4 weeks,titanium screw with a diameter of 2.0mm were implanted into the distal femur and proximal tibia of both diabetic rats and normal control rats.Blood glucose was detected weekly after prosthesis implantation,and rats were sacrificed for micro-ct scan,histological examination of hard tissue section and biomechanical examination of bone trabeculae at 4w,8w and 12 w postoperatibely,respectively.Results:1.Diabetic animal model: By comparison,it was found that the blood glucose of rats in the DM group was stable at a high level,their body weight was significantly lighter,their consumption of drinking water was significantly faster,their hair color was significantly dim,and there were significantly more feces(urine and feces)in the rat cage,which proved that the diabetic rat model had been successfully established.2.Micro-ct scan:(1)three-dimensional reconstruction image: compared with the normal control group,the bone mass around the titanium screw was lower in the diabetic group,the bone tissue texture was weak,and the trabecular bone arrangement was sparse and irregular.(2)Trabecular bone parameters: at 4w,8w,and 12 w a fter the implantation of prosthesis,the thickness,number,surface area fraction,and volume fraction of the titanium screw trabecular were significantly lower in the diabetic group than in the normal control group,while the trabecular spacing was significantly higher than in the normal control group,all P < 0.05.3.Biomechanical test: at 4w,8w,12 w after surgery,the maximum load of the prosthesis extraction experiment in the diabetic group was significantly lower than thar in the normal control group,and the difference was statistically significant(P<0.01).4.Soft tissue sections: in the DM group,the bone tissue around the titanium screw thread was disordered,with less new bone tissue,poor maturity and continuity,and more voids between the titanium screw thread and the bone.5.Hard tissue sections:(1)staining observation: at 4w,8w,and 12 w after the implantation of titanium screw,the bone tissue around the titanium screw was disordered,the new bone tissue was less,the maturity and continuity were poor,and there were many gaps between the titanium screw screw and the bone.(2)data analysis: at 4w,8w and 12 w after the implantation of titanium screw,the area ratio of titanium screw nailing in the diabetic group was significantly lower than that in the normal control group.Conclusions:Diabetes can affect the bone growth of titanium screw,which is manifested as the disorder of the arrangement of bone tissue around the prosthesis,the lack of new bone tissue,poor maturity and continuity,and the poor parameters of trabecular bone,such as the thickness,number,bone surface area fraction,bone volume fraction and trabecular septum.