Establishment Of Rabbit Model Of Traumatic Arthritis Articular Cartilage Defect And Study Of Its Early Articular Cartilage Defect Repair

PART ?:Establishment?analysis and identification of a cartilage defect model of rabbit traumatic arthritisOBJECTIVE: To explore a method for the establishment of a model of rabbit knee arthritis that is consistent with clinical traumatic arthritis,inflammatory environment changes in joints,and articular cartilage defects.Methods: Three-month-old New Zealand white rabbits were sacrificed under sterile conditions to establish an unstable environment by severing the medial collateral ligament and anterior cruciate ligament of the knee joint.Simultaneous removal of the medial meniscus and establishment of perforation in the medial femoral condyle established early In the mid-term rabbit knee arthritis cartilage defect model,the gross appearance and Histomorphological changes of rabbit knee joints were observed at different time intervals,and pathological sections were prepared for histological scoring.The knee articular cartilage degeneration in each group of experimental animals was compared and compared.Conduct the analysis.Results: From the aspect of appearance,arthritis showed a progressive increase in the cartilage breakage,and the cartilage defect range was progressively increased in the animals after modeling;at 4 weeks,there was a thin layer of translucent tissue repair at the 4th week,8 weeks.At the time of milky white tissue hyperplasia,some of the cartilage was worn around,and the articular cartilage became thin and uneven.At 12 weeks,there was a wide range of cartilage wear.The cancellous bone was visible in the deep,and the fibrous tissue was surrounded by adhesion and adhesion.The joint activity was obviously affected.In the limit,cartilage tissue appeared extensive abrasion at 16 weeks,fibrous connective tissue and epiphyseal hyperplasia,articular surface loss of luster and normal morphology,joint cavity adhesions,activity disappeared.Histologically,normal chondrocytes gradually disappeared and the fibrous tissue cells proliferated.Conclusion: The medial collateral ligament and anterior cruciate ligament of the rabbit hind leg were cut off,the medial meniscus was removed,and the medial femoral condylar articular surface was perforated.The articular cartilage of the articular surface was destroyed while changing the knee joint stress and could be formed within a short period of time.An experimental model of osteoarthritis in a traumatic articular cartilage defect bearing a traumatic knee.PART ?:Study on Repair of Cartilage Defects in Rabbit Model of Early Arthritis and Rabbit Knee ArthritisObjective: To investigate the repair of articular cartilage defects of load bearing face with poor internal environment using thermosensitive hydrogels of chitosan,platelet-rich fibrin(PRF)and BMSCs/PRF chitosan thermosensitive hydrogels.Explore the ability to repair old cartilage defects with poor internal environment.Methods: Rabbits that have been successfully modeled for 4 weeks were entered from the original surgical incision of the knee joint.The granulation tissue of the old defect was removed with a hand-drill and the filling was filled into the gap.The medial collateral ligament was sutured and repaired as far as possible.Anterior cruciate ligament,a total of three treatment groups(chitosan group,PRF group,complex group)were established,with 15 rabbits in each group.After the defect was repaired,it was divided into three periods of 4 weeks,8 weeks,and 12 weeks.The joints were removed and scored according to ICRS and Cook's gross scores.Specimens were prepared and paraffin sections were prepared,stained(HE staining,aliocyanine staining,safranin-O staining,and type II collagen immunohistochemical staining)to detect staining changes and analyzed by Wakitani's histological scoring.Results: The synovial tissues of 45 rabbits showed different degrees of hyperplasia and hypertrophy.Chitosan group: The cartilage defect was obvious at each time period.In the early stage,a little fibrin covered the bottom of the defect,then the cartilage surface gradually began to degenerate,the cartilage cells appeared nuclear condensation,and the joint surface was deformed;in the PRF group,there was a gradual half of the defect.The formation of transparent repair tissue,the color is similar to the surrounding normal tissue,the surface is basically smooth,smooth,no significant boundary with the fusion of adjacent tissue,there are chondrocyte production,type II collagen formation.In the composite group,the cartilage defect of the knee joint was well repaired,and the new cartilage was similar to the surrounding tissue in the general view and staining.A large number of chondrocytes and type II collagen were observed.Conclusions: 1.Chitosan stent is very weak in the repair of old cartilage defects in rabbit knee traumatic arthritis.2.PRF has a certain repair effect on the old cartilage defect of knee traumatic arthritis,indicating that cytokines have a certain effect on the repair of articular cartilage defects.3.The old cartilage defects of traumatic arthritis in rabbits and rabbits were better than those in chitosan and PRF.