The Experimental Comparison The Rabbit Femoral Condylar Defects Repaired With Alendronate/Calcium Phosphate Cement, Calcium Phosphate Cement And Allografts Bone

ObjectiveTo investigate the effect of CPC loaded with ALN,CPC and allografts bonerepaired on rabbit femoral bone defects.All groups were collected forX-ray,mechanical test,qualitation and quantitation of histological examination,thegroup was compared with each other,and provide reference for clinical usage.MethodThe bilateral femoral condylar defects model(4mm in diameter,10mm indeepness)were established in36adult and healthy New Zealand rabbits, which wererandomly divided into3groups(n=12);CPC as drug delivery system loaded withALN(group A),CPC(group B), allografts bone(group C) were implanted in the defects.At3and6months after the operation, all specimens were collected for mechanicaltest, qualitation and quantitation of histological examination.ResultsBiomechanical testing results showed: at3months of the defects, group A（39.54±4.40）M pa, group B（31.66±6.12）M pa, group C（18.83±3.35）M pa, at6month, group A（45.01±3.87）M pa，group B（33.47±5.46）M pa，group C（23.07±3.51）M pa, at3and6months, there was statistically significant difference when the3groups were compared in pairs. The midshaft of femur at3months, groupA（25.18±5.54）M pa，group B（16.05±3.61）M pa，group C（15.35±4.27）M pa，at6months, group A（31.38±4.96）M pa，group B（16.84±3.87）M pa， group C（16.61±4.07）M pa, the result of the compressive strength of the midshaft of femurare following, group A increased obviously when compared with those of groups Band C(p＜0.05)，and there was no significant difference between groups B and C（p＞0.05）. The outcomes of the histological examination are following, at3monthsafter operation, there were different degrees of new bone tissue regeneration aroundthe groups of A、B、C, and the material of groups A and B partly degraded, new bonetissue combined with material tighter when compared with group C. At6months, Thematerials had further degradation in the groups A and B, and new bone tissue growthinto the gap, besides, group A was better than group B in bone growth.，there was nosignificant change compared with the previous in the group C. The quantitativeanalysis results at3months, group A（27.66±4.28）%，group B（15.23±4.61）%，group C（6.34±5.82）%，at6months, group A36.35±5.71）%，group B（19.37±5.60）%， group C（10.67±4.49）%, there was statistically significant difference when the3groups were compared in pairs，and the percentage of the bone tissue at6monthsafter operation was obviously higher than that at3month.ConclusionCPC as drug delivery system loaded with ALN could rapidly restore the defects of rabbitfemoral condylar and increase the strength of femur compared with CPC，allografts bone.