兔异体骨-前交叉韧带-骨移植重建前交叉韧带术后早期组织学与生物力学观察

Reconstruction of anterior cruciate ligament with bone-anterior cruciate ligament-bone allograft in rabbits:a prophase study with histology and biomechanics

目的对兔同种异体骨-前交叉韧带-骨(bone-anterior cruciate ligament-bone,B-ACL-B)移植重建ACL术后早期(12周)移植物进行组织学观察及生物力学测试。方法 24只骨骼成熟新西兰大白兔,用新鲜冰冻异体B-ACL-B移植重建兔前交叉韧带,术中及术后均不使用免疫抑制剂。分别于术后3、6、12周对重建后的移植物进行大体观察、组织学观察及生物力学测试,对照组为自体正常侧ACL。结果重建术后早期移植物在关节内经历了植入物坏死、细胞长入、胶原纤维再生过程。术后移植物内大量成纤维细胞增殖,6周时最明显。术后原胶原纤维变性坏死,皱褶明显,小胶原纤维再生,12周时新生小胶原纤维排列较规律、致密。术后3、6、12周移植物最大抗拉载荷分别为(5.6±0.9)、(14.9±2.3)、(42.6±3.7)N,分别是正常ACL[(102.6±7.8)N]的5.5%、14.5%、41.5%,4组最大抗拉载荷的总体变异差异有统计学意义(P<0.05)。结论应用相同解剖学及组织学类型的兔异体B-ACL-B重建ACL,术后早期移植物组织学及生物力学表现良好。

Objective To observe the prophase histology and biomechanics in the reconstructed anterior cruciate ligament（ACL） with bone-anterior cruciate ligament-bone（B-ACL-B） allograft in rabbits.Methods Based on the study of anatomy,histology and biomechanics of normal rabbit ruciate ligaments,ACLs were reconstructed with B-ACL-B complex allografts in rabbits.Twenty-four skeletally matured New Zealand white rabbits underwent ACL reconstruction with aseptically harvested fresh-frozen B-ACL-B allograft on one knee randomly.No any immunosuppressive agent was used intra-operative and post-operatively.Gross observation,histological examination and biomechanics test were performed in these groups at 3,6 and 12 weeks after operation.The opposite side of normal ACL served as control.Results In the early period,the allograft tissue underwent a gradually healing process including the graft necrosis,cellular migration and collagen formation.After operation,a lot of fibroblasts were found in each period,especially at 6 weeks.The virgin collagen fibers crimped and degenerated,and the new collagen fibers were formed.At 12 weeks,the new collagen fibers organized regularly and tightly.The maximum loads of the allograft was 5.5%（5.6±0.9 N） after 3 weeks,and 14.5%（14.9±2.3 N） after 6 weeks,and 41.5%（42.6±3.7 N） after 12 weeks.The maximum loads of the control group was 102.6±7.8.There was significant difference among 4 groups in maximum loads（P0.05）.Conclusion The ACL reconstructed with graft of same anatomic and histological tissue can achieve a good result in prophase histological and biomechanics.