Early Effect Of Bone Trabecular Metal Cone In The Reconstruction Of Aori Type Ⅱ And Ⅲ Metaphyseal Bone Defects Of Knee Joint

Objective: To investigate the early effect of bone trabecular metal cone in the reconstruction of AORI type Ⅱ and Ⅲ metaphyseal bone defects of knee joint in complex primary knee arthroplasty and revision.Methods: From July 2015 to January 2019,18 patients(19 knees)who underwent complex primary knee arthroplasty and revision and used trabecular metal cone to reconstruct AORI type Ⅱ and Ⅲ metaphyseal bone defects of knee joint were retrospectively analyzed.Among them,there were 6 males and 12 females,aged 38-80 years,with an average age of 66.4 years,BMI value of 21.9-35.7,with an average age of 26.6.There were 2 cases of primary knee arthroplasty and 17 cases of revision knee arthroplasty.During follow-up,ROM,VAS and AKS scores of knee joint were evaluated,Long Leg Radiographs and X-ray films of knee joint were reexamined,force lines of knee joint were measured,bone penetration of trabecular metal cone was observed,and complications were recorded.Results: Eighteen patients were followed up for 5 to 47 months,with an average of 18.6 months.During the last follow-up,one patient had fracture of the middle femoral shaft 20 days after operation,and the other patients had no complications such as prosthesis-related infection,dislocation and peripheral fracture.AKS score increased from preoperative(46.7±9.6)to(82.7±10.3).The difference was statistically significant(t =-14.98,P < 0.05).VAS score decreased from preoperative(4.5±1.24)to(1.22±1.16).The difference was statistically significant(t = 14.512,P < 0.001);knee joint mobility changed from preoperative(52.8 ±38.9)to(84.9±29.5)degrees(t = 3.868,P < 0.05).The FTA of knee joint changed from(169.8±9.1)degree to(174.9±1.7)degree,and the difference was statistically significant.During the last follow-up,17 patients(94.4% 17/18)had good bone ingrowth,no osteolysis was found,no aseptic loosening caused by bone resorption,and all the prostheses were firmly fixed.Conclusion: Trabecular metal cone can effectively fill AORI Ⅱ and Ⅲ metaphyseal bone defects of knee joint during primary knee arthroplasty and knee revision.Bone ingrowth in cone is good,initial stability of knee prosthesis is strengthened,mechanical alinement of knee joint is reconstructed,and knee joint function is obviously improved.