The Experimental Study Of The Patellar Tendon's Reconstruction In Tumor Knee Replacement

Objective and significanceWe will undergo an experiment that the patellar tendon of rabbits is reconstructed with a neotype devised upper tibia prosthesis.Through the experiment,we want to obtain a firmer effectiveness of the reconstruction of the patellar tendon-prosthesisbone in rabbits,and the method and its base theory of the patellar tendon reconstruction after the tumor in the upper tibia of the human body is exsected Material and MethodsOur experimental animal are rabbits,and the rabbits' upper tibia prosthesis is designed by ourselves,we carry out the animal experiment by imitating the key-place in the upper tibia of the mankind in clinic,where patellar tendon is reconstructed.The experimental animal:72 of homogeneity white rabbits from New-Zealand provided by Animal Experimental Center of Kunming Medical College.Their weight range 2.5 Kg to 3.5Kg,and their gender are not limited.They are divided into three groups randomly,and every group has 24 rabbits.Every group is divided three small sequentially,and every small group has 8 rabbits.We establish 3 type of models of rabbits,which are patellar tendon -prosthesis-bone(A group,experimental group,EG) and patellar tendon-prosthesis(B group,control group,CG) and patellar tendonligament (C group,control group,CG).EG A is the model of patellar tendon -prosthesis-bone which is implanted rabbit medial thigh muscles.In our body,we can use caput mediale musculi gastrocnemii to cover the anterior surface of the tibia prosthesis.So the reconstruction of patellar tendon in the rabbit and mankind have the same vivo environment.CG B and CG C are used to contrast with EG A.CG B is the type of patellar tendon-prosthesis,which be implanted rabbit medial thigh muscles as well.CG C is the type of patellar tendon-ligament,that patellar tendon is to be coincided by broken ends of patellar tendon directly,we contrast the different models' changes in aspects of biomechanics and pathology when the time is go to the point in time we set ahead.The points in time are the 4th weekend and the 8th weekend and the 12th weekend.4 weeks after operation,8 rabbits(Al/Bl/Cl) from A/B/C group are executed and the specimens are acquired.The specimen is the prosthetic patellar tendon in left leg,and general form of the specimens be observed with the naked eye. Then,the biomechanics data of the prosthetic patellar tendon are measured.The healing junction of the prosthetic patellar tendon are be done pathological examination,and to study the healing status of patellar tendon by different method of reconstruction.In the same way,other rabbits will be carried the procedure in 8 weeks or 12 weeks.All the data collected will be done by statistical analysis.Result1.Pathology results:Histological examination showed that the tendon-bone interspace of EG A was filled with considerable osteoblasts at the end of 4 weeks,and surrounding hyperplastic fiber and infiltrative inflammatory cells.At the end of 8 weeks,the tendon-bone interspace formed array-intensive Sharpey fiber,including small amounts of osteoblasts.Immature fibrocartilages and newly form bone appear in the tendon-bone at the end of 12 weeks,and fiber connection between the tendon-bone can be seen as well.The histological changes between CG B and CG C are uniform approximately,but the histological change in CG C is better than that in CG B at the point in time.Hyperplasia of fibrous tissue and infiltrative inflammatory cells are form at the end of tendon and surrounding at the end of 4 weeks.When 8 weeks,some of fiber tissue began to be collagenous degeneration,and the fiber tissue structure become intensive,inflammatory cells reduce obviously.At the end of 12 weeks,the fiber tissue shows tight,and less inflammatory cells. 2.Biomechanics result:every small group(8 rabbits) underwent biomechanics examination at the end of 4 weeks or 8 weeks or 12 weeks after being operated.EG A show much more anti-tensile strength than CG B/C at 4 weeks/8 weeks/12 weeks point in time.EG A>CG B/C,the difference of the comparison is of statistical significance(P<0.01).EG C > EG B(P<0.05).The anti-tensile strength of all groups(A/B/C) enhance increasingly with the time prolonging,and the difference of the comparsion is of statistical significance(P< 0.01).Conclusion1.The reconstruction measure of patellar tendon -prosthesis-bone is much better than that of patellar tendon-prosthesis or patellar tendon-ligament on the aspect of biomechanics,and have significance anti-tensile strength after being operated.2.With the prolonging of the time,every group's anti-tensile strength gradually increased.The reconstruction way of the patellar tendon-prosthesis-bone has a significant enhancement.3.The model of the patellar tendon-prosthesis-bone can reach tendon-bone healing, and that makes patellar tendon's reconstruction reach biological healing.While the patellar tendon-ligament's gains the reconstruction by scar adhesion healing and tie healing,and patellar tendon-ligament's gains the reconstruction by tendon-scarligament healing mainly.4.Through well-designed bone graft prosthesis for reconstruction of patellar tendon,the patellar tendon can provide a greater driving force,and the stability of the knee.