目的探讨动力髋螺钉(DHS)、股骨近端防旋髓内钉(PFNA)、Inter Tan 3种内固定材料固定股骨粗隆下骨折生物力学性能,为临床选择有效内固定方式提供科学依据。方法采购人工股骨标本18根,按照Seinsheimer分型Ⅲa型予以截骨制作成粗隆下骨折...目的探讨动力髋螺钉(DHS)、股骨近端防旋髓内钉(PFNA)、Inter Tan 3种内固定材料固定股骨粗隆下骨折生物力学性能,为临床选择有效内固定方式提供科学依据。方法采购人工股骨标本18根,按照Seinsheimer分型Ⅲa型予以截骨制作成粗隆下骨折模型,分别用3种内固定材料固定,进行股骨的强度、刚度、稳定性、承载能力测式等生物力学实验,分析比较3种内固定方式固定股骨粗隆下骨折的生物力学性能。结果实验力学结果表明:Inter Tan髓内钉固定强度为(1.84±0.15)MPa,DHS为(1.39±0.11)MPa,PFNA为(1.36±0.12)MPa内固定的强度,Inter Tan组内固定强度大于DHS组和PFNA组,差异有统计学意义(P<0.05);Inter Tan组刚度EF为(945.35±82.01)N/mm,DHS为(638.54±78.21)N/mm,PFNA为(755.33±86.32)N/mm,Inter Tan组刚度大于DHS组和PFNA组,差异有统计学意义(P<0.05);Inter Tan组的抗剪、抗扭的稳定性、承载能力均明显优于DHS、PFNA组,差异有统计学意义(P<0.05);其动态力学性能疲劳寿命也相应比DHS、PFNA组优越。结论 Inter Tan及PFNA均是固定Ⅲa型股骨粗隆下骨折的理想方法,其中Inter Tan整体生物力学性能优于PFNA髓内钉固定,而DHS不适用于此型股骨粗隆下骨折。展开更多
Gauge length influences the biomechanical properties of herbaceous roots such as tensile resistance,tensile strength and Young’s modulus.However,the extent to which and how these biomechanical properties of herbaceou...Gauge length influences the biomechanical properties of herbaceous roots such as tensile resistance,tensile strength and Young’s modulus.However,the extent to which and how these biomechanical properties of herbaceous roots are influenced remain unknown.To better understand the behavior of roots in tension under different conditions and to illustrate these behaviors,uniaxial tensile tests were conducted on the Poa araratica roots as the gauge length increased from 20 mm to 80 mm.Subsequently,ANOVA was used to test the impact of the significant influences of gauge length on the biomechanical properties,nonlinear regression was applied to establish the variation in the biomechanical properties with gauge length to answer the question of the extent to which the biomechanical properties are influenced,and Weibull models were subsequently introduced to illustrate how the biomechanical properties are influenced by gauge length.The results reveal that(1)the variation in biomechanical properties with root diameter depends on both the gauge length and the properties themselves;(2)the gauge length significantly impacts most of the biomechanical properties;(3)the tensile resistance,tensile strength,and tensile strain at cracks decrease as the gauge length increases,with values decreasing by 20%-300%,while Young’s modulus exhibits the opposite trend,with a corresponding increase of 30%;and(4)the Weibull distribution is suitable for describing the probability distribution of these biomechanical properties;the Weibull modulus for both tensile resistance and tensile strain at cracks linearly decrease with gauge length,whereas those for tensile strength and Young’s modulus exhibit the opposite trend.The tensile resistance,tensile strength,and tensile strain at the cracks linearly decrease with increasing gauge length,while the tensile strength and Young’s modulus linearly increase with increasing gauge length.展开更多
目的测试颈椎钩椎关节融合器的初始稳定性。方法将20具山羊颈椎标本随机分为完整颈椎组、自体髂骨块植入组、钩椎关节融合器植入组、传统椎间融合器植入组四组,采用非破坏弹性法对山羊C 3~4节段进行过伸/过屈、左右侧屈以及轴向旋转活...目的测试颈椎钩椎关节融合器的初始稳定性。方法将20具山羊颈椎标本随机分为完整颈椎组、自体髂骨块植入组、钩椎关节融合器植入组、传统椎间融合器植入组四组,采用非破坏弹性法对山羊C 3~4节段进行过伸/过屈、左右侧屈以及轴向旋转活动范围(range of motion,ROM)测试。结果钩椎关节融合器组、零切迹融合器对照组在前屈、后伸、左右侧屈、轴向旋转维度上角位移与髂骨块植入组均差异有统计学意义(P<0.05);钩椎关节融合器组和零切迹融合器对照组过伸/过屈ROM差异无统计学意义(P>0.05),但钩椎关节融合器组左右侧屈ROM和左右旋转ROM略小于零切迹融合器对照组,差异有统计学意义(P<0.05)。结论钩椎关节融合器在左右侧屈与轴向旋转方面稳定性略优于传统零切迹椎间融合器,在前屈/后伸方面与传统零切迹椎间融合器稳定性相当。展开更多
基金financially supported by the Key R&D Program of Shaanxi Province(2023-YBSF-324)Shaanxi Provincial Department of Education Services Local Special Plan Project(23JC019)National Natural Science of Foundation of China(42267024).
文摘Gauge length influences the biomechanical properties of herbaceous roots such as tensile resistance,tensile strength and Young’s modulus.However,the extent to which and how these biomechanical properties of herbaceous roots are influenced remain unknown.To better understand the behavior of roots in tension under different conditions and to illustrate these behaviors,uniaxial tensile tests were conducted on the Poa araratica roots as the gauge length increased from 20 mm to 80 mm.Subsequently,ANOVA was used to test the impact of the significant influences of gauge length on the biomechanical properties,nonlinear regression was applied to establish the variation in the biomechanical properties with gauge length to answer the question of the extent to which the biomechanical properties are influenced,and Weibull models were subsequently introduced to illustrate how the biomechanical properties are influenced by gauge length.The results reveal that(1)the variation in biomechanical properties with root diameter depends on both the gauge length and the properties themselves;(2)the gauge length significantly impacts most of the biomechanical properties;(3)the tensile resistance,tensile strength,and tensile strain at cracks decrease as the gauge length increases,with values decreasing by 20%-300%,while Young’s modulus exhibits the opposite trend,with a corresponding increase of 30%;and(4)the Weibull distribution is suitable for describing the probability distribution of these biomechanical properties;the Weibull modulus for both tensile resistance and tensile strain at cracks linearly decrease with gauge length,whereas those for tensile strength and Young’s modulus exhibit the opposite trend.The tensile resistance,tensile strength,and tensile strain at the cracks linearly decrease with increasing gauge length,while the tensile strength and Young’s modulus linearly increase with increasing gauge length.
文摘目的测试颈椎钩椎关节融合器的初始稳定性。方法将20具山羊颈椎标本随机分为完整颈椎组、自体髂骨块植入组、钩椎关节融合器植入组、传统椎间融合器植入组四组,采用非破坏弹性法对山羊C 3~4节段进行过伸/过屈、左右侧屈以及轴向旋转活动范围(range of motion,ROM)测试。结果钩椎关节融合器组、零切迹融合器对照组在前屈、后伸、左右侧屈、轴向旋转维度上角位移与髂骨块植入组均差异有统计学意义(P<0.05);钩椎关节融合器组和零切迹融合器对照组过伸/过屈ROM差异无统计学意义(P>0.05),但钩椎关节融合器组左右侧屈ROM和左右旋转ROM略小于零切迹融合器对照组,差异有统计学意义(P<0.05)。结论钩椎关节融合器在左右侧屈与轴向旋转方面稳定性略优于传统零切迹椎间融合器,在前屈/后伸方面与传统零切迹椎间融合器稳定性相当。
