Scoliosis Induced By Cutting Gramus Posterior Nervorum Spinalium On Rabbits

ObjectiveTo observe whether scoliosis is produced by only cutting off ramus posterior nervorum spinalium and to discuss the correlation between the denervation of paravertebral muscles and development of idiopathic scoliosis.Materials and Methods1,Experimental AnimalsGrowing Japanese rabbits weighting 500 to 700g and ranging from 4 to 6 weeks old were used.Experiments started with 80 rabitts and were divided randomly into 14 groups(n=5).2,Empirical methodExperimental groups had 40 rabbits and right ramus posterior nervorum spinalium were cut off.Control groups had 30 rabbits and undergone the same operation as experimental groups,but without cutting off right ramus posterior nervorum spinalium.Postoperative radiographs were performs three times until the 12th postoperative week at 4-week interval.After The paravertebral muscles of denervation at the 12th postoperative week were stained with hematoxylin and eosin to oberserve the histoligic features.3,Evaluation of resultPostoperative radiographs were performs three times until the 12th postoperative week at 4-week interval to observe condition of scoliosis.After The paravertebral muscles of denervation at the 12th postoperative week were stained with hematoxylin and eosin to oberserve the histoligic features assessing the atrophy of paravertebral muscles in the side of denervation.ResultsAlthought the paravertebral muscles of denervation at the 12th postoperative showed obvious atrophy,all groups did not produce scoliosis that the apex of the curvature was toward the side of denervation.Conclusions1,Scoliosis that the apex of the curvature was toward the side of denervation can not be produced by the method.2,Thus the authors think the denervation of paravertebral muscles may not be etiological factor of idiopathic scoliosis.3,The true etiology of idiopathic scoliosis remains unknown;however,it appears to be multifactorial.4,The reason that scoliosis that the apex of the curvature was toward the opposite side of denervation were produced is the contraction of muscle scar at postoperation.