Biomechanics Studie Of Polyaminoacid/Nanohydroxyapatite Cage In A Goat Cervical Spine Fusion Model

Objective: To assess the biomechanical feasibility ofpolyaminoacid/nanohydroxyapatite bioabsorbable cervical fusioncage(n-PAA/HA BCFC) replacing autogenous iliac crest bone graft inanterior cervical decompression(ACDF) of a goat and to providetheoretical basis for clinical application of n-PAA/HA BCFC by implantingn-PAA/HA BCFC and autogenous iliac crest bone graft into the cervicalvertebra respectively, and comparing the state of intervertebral fusion byX-ray and the biomechanics of two groups after fusion.Methods: Ten adult female goats underwent C3/4discectomy andintervertebral fusion with n-PAA/HA BCFC(n=15) or autogenous iliac crestbone graft(n=15), which were fixed by plates.12weeks postoperatively, allthe goats were killed to get cervical vertebraes. Then observe and give ascore to the state of intervertebral fusion, and nondestructive biomechanicaltest(flexion, extension, lateral bending, axial rotation) were performed forcalculating the stiffness and range of motion(ROM) of the n-PAA/HA BCFCgroup and autogenous iliac crest bone graft group. Finally, collect all the datas and make a comparison.Results: According to the observation and radiographic score of X-rayof two groups, the fusion speed of the group of n-PAA/HA BCFC wasfaster, which means the the group of n-PAA/HA BCFC demonstrated asignificantly(P<0.05) higher score. And according to the test ofbiomechanics(flexion, extension, lateral bending, axial rotation) of twogroups, there was a significantly differences(P<0.05) in ROM and instiffness between the group of autogenous iliac crest bone graft and thegroup of n-PAA/HA BCFC. In a word, the n-PAA/HA BCFC group showeda better biomechanics than the autogenous iliac crest bone graftgroup(P<0.05).Conclusion: From the study, the group of n-PAA/HA BCFCdemonstrated a higher fusion speed and better biomechanics. So then-PAA/HA BCFC can provide enough biomechanics before fusion.Although, before the n-PAA/HA BCFC is used in the clinical, it isconsiderable that we should keep doing much more researches on thehistology and optimize the propotion of this material, and add the BMP intothe material, which maybe cause a better satisfactory fusion andbiomechanics.