Experimental Study Of The Adjacent Cervical Disc Degeneration After The Operation Of Anterior Cervical Decompression And Orthotope Bone Graft Plate

Objective: To study the morphological differences of adjacent intervertebral discs between Anterior Cervical Decompression And Orthotope Bone Graft Plate with Anterior Cervical Decompression And Ilium Crest Graft Plate Internal Fixation.This in vivo experiment may premote the utility of the Anterior Cervical Decompression And Orthotope Bone Graft Plate in clinic surgery with the evidence of its advantage.Methods: 9 normal mature goats, female, the weight between 30～40kg, the age between 3～4 years old. Goats were divided into three groups( I , II, III) randomly and evenly. The Group I was a normal control without any dispose; The Group II was operated by Anterior Cervical Decompression And Orthotope Bone Graft Plate; The Group III was operated by Anterior Cervical Decompression And Ilium Crest Graft Plate Internal Fixation. The Operation site was C3/4. All groups were took the X-rays at preoperative, postoperative, and after the operation 1,3, 6 month, to contrast the fusional dgree and the height of the adjacent intervertebral space. After 6 months of operation, we cut the adjacent intervertertebral discs of Group I and Group II,III which was proved already fused by X-ray,made them into electron microscopy specimens and analysed as well as observerd the morphological differences of the ultrastructure under transmission electronic microscopy. We removed the C2/3 and C4/5 disc contains a little vertebrae after killing the goats, preparated specimens for light microscopy investigating.Results: (1)After 6 month,all the operated groups were radiological fusion.The intervertebral space of the operated disc is still remaining in Group II, but have bony fusion in Group III. Before and 6 months after the operation,compared the height and the lost height of the adjacent intervertebral space relatively,three groups had no significant difference. (P>0.05); (2) Three groups evaluated by the Miyamoto Standard of light microscopy, though the degree of degeneration became slight to severe from Group I to Group III, but without statistical significance (P>0.05); (3) Take the group I as the contral group and observe the ultrastructure comparely. The degeneration of Group II ,Group III was mild,mostly severe respectively.The result of cell Count under different degree degeneration, Group II with statistical significance compared to Group I , III relatively (P<0.05); there was high statistical significance between the Group III and the Group.Conclusions: (1) We can build a satisfying experimental animal model of the anterior cervical surgery by goat; (2) Anterior cervical fusion may result in degeneration at the adjacent intervertebral discs; (3) The effect at the adjacent intervertebral discs of the Anterior Cervical Decompression And Orthotope Bone Graft Plate was markedly lighter than the Anterior Cervical Decompression And Ilium Crest Graft Plate Internal Fixation. (4) The further research of Anterior Cervical Decompression And Orthotope Bone Graft Plate is of great value to premote its utility in future clinic.