颈椎前路生物活性玻璃涂层钛板系统的研制与生物力学评价

目的 研制颈椎前路生物活性玻璃钛板系统(ACBPS),并对其进行生物力学评价。方法 在钛板内面及螺钉表面等离子喷涂0.3mm厚的生物活性玻璃涂层。采用18具颈椎标本随机分为ACBPS、颈前路钛板系统(ACPS)、和Orion三组,在颈前路减压、植骨及钛板内固定后,行载荷-位移、扭矩和扭转刚度、极限力学性能测定并记录结果,进行对比;另对ACBPS、ACPS行拔出试验和疲劳试验,且以三维有限元素分析验证。结果 在前屈、后伸时ACBPS组的纵向位移降低幅度明显高于ACPS组或Orion组,同时其纵向位移值明显低

DESIGN AND BIOMECHANICAL EVALUATION OF ANTERIOR CERVICAL BIOGLASS-COATING PLATE SYSTEM

Objective To evaluate the biomechanical properties of self- designed anterior cervical bioglass- coating plate system (ACBPS) . Methods A 0.3mm coating thickness of bioglass was sprayed isoionically onto the surface of the screws and the reverse side of the plate. 18 cervical spine specimens(C2 -T1)were divided into three groups. After decompression, bone graft and implant fixiation with ACBPS, ACPS or Orion, the load-displacement, torque, twisting stiffness and ultimate mechanical performance were tested and compared. Furthermore, ACBPS and ACPS were subjected to pull-out test and fatigue test, and the results were further justified with a three dimensional finite element model. Results The results showed that the ranges of displacement decrease of ACBPS group was more significant than those of ACPS or Orion ( P < 0.05 ) in flexion-extension and the longitudinal displacements after fixation were lower ( P < 0.05 ) than those two implant groups as well. But torque,twisting stiffness and ultimate mechanical performance of ACBPS group were similar to those of ACPS or Orion ( P > 0.05 ) group. The maximum pull-out force and its relative displacement and energy absorption of ACBPS were greater than those of ACPS or Orion ( P < 0.05 ) . Its fatigue strength was 586.86MPa and could bear 6.55 · 105 times of loading on average before they appeared fissures externally to the screw holes. Althougth the stress concentration was located circum-ferentially of the holes of ACBPS, the diameter of holes and the distance of edges were still in the margin of safety. Conclusion ACBPS can not only provide sufficient biomechanical stability and prevent the loosening of screws or the system, but also reduce the stress concentration on the holes of the plate by its bioglass coating which prolongs its service life and is safe for long - time internal fixation.