ABSTRACT
Objective: To establish an animal model for anterior cervical-adjustable fusion fixator (AC-AFF), and to compare the operation time, blood loss, and recovery time of food intake and movement between AC-AFF group and other groups with different cervical reconstruction fixators. Methods: Eighteen goats were evenly randomized into 3 groups: AC-AFF, steel plate+ titanium mesh, and steel plate+autogenous iliac bone group. The 3 fixtors were implanted after corpectomy. The operation time, blood loss during operation, and recovery time of food intake and movement were recorded in each animal and were compared. Results: All experiment animals survived after operation; one animal of steel plate+titanium mesh group suffered from incision infection and recovered 5 days after intramuscular penicillin therapy. Two animals in steel plate+autogenous iliac bone group could not stand on forehoof, but food intake was not influenced; the animals could stand 1 week later without treatment and walked with difficulty, and they recovered normal walk 2 weeks later. Four animals received C3 corpectomy (2 received AC-AFF and 2 received steel plate+titanium mesh) and the rest received C4 corpectomy. It was found that AC-AFF group had the shortest operation time (P<0.01), and there was no difference between the other 2 groups. The intra-operation blood loss in the steel plate+autogenous iliac bone group was significantly higher than that in the other 2 groups (P<0.01), with no significant difference found between the latter 2 groups. Conclusion: AC-AFF is easier to manage than the other 2 fixators; besides, AC-AFF has less blood loss, short operation time, less post-operation complication, and early recovery of food intake and movement.
ABSTRACT
Objective: To observe the bone graft fusion of goat cervical model implanted with anterior cervical-adjustable fusion fixator(AC-AFF), laying a foundation for future studies. Methods: Eighteen experiment goats were implanted with AC-AFF, titanium mesh and autogenous iliac bone combined cervical plate after corpectomy. Six months later, the fused cervical spine vertebrae were collected, prepared, and observed grossly, under microscope, by X-ray photographs and CT scan; the fusion of the graft was evaluated. Meanwhile, the fusion of AC-AFF with the adjacent vertebral surface was observed. Results: All the experiment animals survived after operation; all the implants were stable, without displace or loosening. The interface where the titanium or AC-AFF contacts the vertebral body surface was bulged and ossified. All iliac bone graft fused well and a great deal of bony callus was found covering the vertebral body surface. Lucency area was not seen surrounding the bone graft, titanium and AC-AFF on the X-ray films, and there was new bone formation in the interface of internal fixation and bone. The central region of titanium and AC-AFF became vague and new bone formation was found in the intracavitary area of implants by CT scan. And part of the new bone transited the parietal reticulation and connected with normal ossea at titanium and AC-AFF. A large number of phoroblasts and chondrocytes were found microscopically in the bone fusion sites in all cases; however, the region without bony callus still existed in the titanium mesh lateral wall. Conclusion: There are no differences in bone fusion between AC-AFF with titanium mesh and autogenous iliac bone combined cervical plate. New phoroblasts and chondrocytes can be generated in the bone graft interface. AC-AFF has been proven as an important method for cervical stability reconstruction after decompression operation.