Establishment of an animal model of cauda equina syndrome and its formative mechanism

doi:10.3321/j.issn:1673-8225.2003.29.007

Abstract：AIM: To establish an animal model of cauda equina syndrome simulate the actual clinical condition to study pathology of cauda equina syndrome.METHODS: Eighty normal adult male New Zealand rabbits were divided into control group, model 1 and 2 groups with compression injury in the cauda equina and spinal nerve root (groups A and B) . Nerve compression was applied to the dural matter and the nerve roots after partial laminectomy in the vertebral canal (1/9, 2/9, 1/2) . The specimens were sampled at different time points after the compression for pathological and immunohis-tochemical study with the nerve functions assessed.RESULTS: Significant neurological changes were observed with 75%restriction of the cauda equina, sacral nerve function grade 1/2 d after the compression in comparison with other time points ( P ＜ 0. 05). Neural tissue damage included inflammatory response in the cauda equina, and axonal and wallerian degeneration followed by Schwarn cell proliferation, axonal bud regeneration and necrosis of the pseudounipolar neurons in the nerve root ganglion. Apoptosis of the anterior horn cells occurred in the conus medullaris.Acute nerve compression can lead to cauda equina syndrome due to canda equina neural tissue damage, whichis most severe 1/2 day after the compression injury.