关键词: 兔, 腰椎解剖, 腰椎间融合模型　

Abstract:

 Objective    In order to provide a standardized model for tissue engineering research，we took  measurement of lumbar bodies on rabbits to establish a stable interbody fusion model.    Methods    Forty-four healthy adult New Zealand white rabbits (2~2.5 kg) were randomly divided into an anatomical analysis group (group A, n=10), an interbody fusion with fixation group (group B, n=12), an interbody fusion with no fixation group(group C, n=12) and a blank control group (group D, n=10). Animals in group B、C、D underwent x-ray examination at 4 weeks after operation. At 12 weeks all rabbits were euthanasized, the fusion segments were tested by manual palpation testing, x-ray, Micro-CT, biomechanical and histological examinations.    Results    Because of the fixed screws into the spinal canal，one case with spinal cord injury in group B suffered paralysis of the lower limbs. The result of manual palpation testing showed the fusion rate of group B is 100% (12/12), while the group C is 75% (9/12). There is no obvious destruction in intervertebral spaces in group D.  The bone graft position of group B was superior to group C and the radiographic score of group B is significantly higher than group C （P<0.05）as shown by imaging tests. The histology indicated there was new formation bone at the fusion position between the interbodies  and only soft tissue existed at the failed fusion position. in biomechanic test， the maximal load of group B was higher than that of group C (P<0.05).    Conclusions    Making a lumbar fusion model on rabbit according to the lumbar anatomy is safe and reliable. The fixation can provide a stable space for the bone grafting fusion ， prevent graft from extruding from the fusion position, as well as do some help to improve the fusion effect.

Key words: Rabbit, Lumbar anatomy,  , Intervertebral fusion model