To observe the histology change of the insertion using different diamertrical bone tunnel in anterior cruciate l igament (ACL) reconstruction. Methods Ninety Japanese rabbits were selected, wihout female and male l imit, weighing 2.5-3.0 kg, and were randomly divided into 3 groups, 30 in each group. The ratio of transplantation l igament diameter and bone tunnel diameter was 1/1 (group A), the ratio was 1/1.5 (group B), and the ratio was 1/2 (group C). Bone tunnel observation and histology observation were carried out in the 4th, 8th and 16th weeks postoperat ively. Results Wound healed well in 3 groups. The mean time of walking functional recovery was 1.5, 2.0 and 3.5 days in groups A, B and C respectively. After 4 weeks of operation, more soft tissues at tunnel entry were observed in group A and group B than in group C; after 8 weeks of operation, there was no crevice at bone-tunnel entry of the groups A and B, there was no improvement in group C; after 16 weeks of operation, groups A and B showed the normal insertion, group C had no normal insertion. Histology observation: in groups A, B and C, bone-tunnel was filled with loose connective tissue after 4 weeks of operation; group A and group B emerged the discontinuation ACL insertion tidal l ine after 8 weeks of operation, group C had no insertion; groups A and B emerged the similarity normal ACL insertion tidal l ine structure after 16 weeks of operation, but group C had no this structure. The results of ultimate tensile strength in groups A, B and C were (75.44 ± 7.06), (91.37 ± 6.14) and (126.91 ± 4.61) N respectively at 4 weeks; the results were (74.31 ± 4.81), (88.30 ± 7.46) and (124.34±8.44) N respectively at 8 weeks; and the results were (62.20 ± 5.32), (71.53 ± 5.99) and (83.62 ± 5.69) N respectively at 16 weeks. There was no significant difference between group A and group B (P gt; 0.05), and there were significant differences between groups A, B and group C (P lt; 0.05). Conclusion In the ACL reconstruction, the ratioof transplantation l igament diameter and bone tunnel diameter being 1/1.5 will not affect the insertion outcome, but if theratio less than the l imit it will affect the insertion outcome.
ObjectiveTo investigate the effect of vascularized peroneus longus tendon graft reconstruction on anterior cruciate ligament (ACL) insertion in rabbits.MethodsEighty healthy New Zealand white rabbits were harvested to prepare ACL injury models and randomly divided into two groups (n=40). The ACL was reconstructed with vascularized peroneus longus tendon graft in group A and peroneus longus tendon graft without blood supply in group B. The survival of animals and the healing of incision were observed after operation; the grafts were taken for gross and histological observations at 4, 8, and 16 weeks; the biomechanical test of the grafts was carried out to record the maximum tensile strength and incidence of ACL insertion rupture at 8 and 16 weeks.ResultsAll animals survived until the experiment completed. General observation showed that the tunnel was combined with grafts, the vascular infiltration was abundant, and no obvious boundary between the tunnel and grafts existed at 16 weeks in group A; there was still an obvious boundary between the tunnel and graft in group B. Histological observation showed that the collagen fibers between tendon and bone in group A increased gradually, the dense fiber connection was formed, and the “tidal-line” like structure similar to the normal ACL insertion was formed at 16 weeks; but the“tidal-line” like structure was not obvious in group B. Biomechanical test showed that there was no significant difference in the incidence of ACL insertion rupture at 8 and 16 weeks between group A and group B (P=0.680; P=0.590), but the maximum tensile strength at 8 and 16 weeks were higher in group A than in group B (t=18.503, P=0.001; t=25.391, P=0.001).ConclusionThe vascularized peroneus longus tendon graft for ACL reconstruction can obviously promote the outcome of the ACL insertion.