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.