1.the first affiliated hospital of south China university;2.Chongqing fuling guo changbi orthopedic hospital
key project supported by chongqing science and health research foundation of traditional Chinese medicine (No.2019ZY013438);
Abstract: objective: To explore the model of axial compression stress induced disc degeneration in goats and evaluate the imaging and pathological features. Methods: Methods: 20 goats were randomly divided into 4 groups (1 control group, 2-4 experimental group, 5 goats in each group).40N axial compressive stress was applied to goat intervertebral discs induced in 2 to 4 groups (4 weeks, 8· weeks, 12 weeks) by self-made axial elastic stress pressure device, and 1 group was used as the control group (no pressure was added).The height and degeneration of intervertebral disc were observed by DHI(DR) and Thompson grading (MRI). The histological changes of intervertebral disc were observed by HE staining and immunohistochemical staining of type 1 and type 11 collagen. Results: in the control group, DHI, Pfirrmann grading, HE staining and immunohistochemical staining of goat intervertebral disc were not statistically significant with the extension of axial compression time (P >0.5).In the experimental group, DHI decreased with the extension of time, which was statistically significant (P < 0.05).HE staining reduced the volume of nucleus pulposus and reduced the number of nucleus pulposus cells, which were gradually replaced by fibrous tissue.Immunohistochemical staining of nucleus pulposus type I collagen was changed from light yellow to yellow to brown-yellow.The staining of type II collagen in nucleus pulposus was from dark yellow to yellow to light yellow.The results indicated that collagen type I increased gradually and collagen type II decreased gradually, and degeneration occurred in the disc. Conclusion: certain axial compression stress can induce the degeneration of lumbar intervertebral disc in goats with the extension of time, and the time of axial compression directly affects the degeneration degree. Therefore, it is reproducible and feasible to construct the animal model of intervertebral disc degeneration.