Influence of diabetes on bone tunnel after anterior cruciate ligament reconstruction in rabbits

Abstract:

Objective：To investigate the influence of diabetes on anterior cruciate ligament（ACL） reconstruction in rabbits and the va－lidity of this animal model. Methods：A total of 36 healthy male New Zealand rabbits were randomly divided into groups A and B. The rabbits in group B were given the injection of alloxan 80 mg/kg via the auricular vein，followed by alloxan 120 mg/kg after 48 hours，and those in group A were given an equal volume of normal saline. After a model of diabetes was established，autologous tendon was used for ACL reconstruction. Gross observation，blood glucose，histology，bone mineral density（BMD），micro-CT，and qRT-PCR were used to observe the influence of diabetes on ACL reconstruction. Results：Gross observation showed that group A had smooth surface and homogeneous texture of the tendon graft in the articular cavity，while group B had rough surface，brittle texture，and yellow color of the tendon graft. From after modeling to 8 weeks after surgery，group B had a significant increase in fasting blood glucose and a significantly higher level of fasting blood glucose than group A（P<0.01）. Histological examination showed that at 8 weeks after surgery，group B had significant reductions in the numbers of pancreatic islets and islet cells（P<0.01）. At 4 weeks after surgery，group A had significantly higher BMD values of the bone tunnel and the surrounding area than group B（P<0.01）；at 8 weeks after surgery，both groups had a significant increase in BMD，and there was a significant difference between the two groups（P<0.01）. Micro-CT showed that compared with group B at 4 and 8 weeks after surgery，group A had a significantly smaller cross-sectional area of the bone tunnel than group B（4.544±0.056） mm2，（3.667±0.095） mm2 vs. （4.734±0.044） mm2，（4.247±0.069） mm2，P<0.05. Conclusion：The rabbit model of alloxan-induced diabetes and ACL reconstruction is safe，reliable，economic，and stable. There is a significant reduc－tion in BMD of the bone tunnel and the surrounding area in di－abetic rabbits after ACL reconstruction，which results in de－layed growth of the bone tunnel.