This study utilized finite element simulation and experimental methods to investigate the evolution of crack detection performanceof a flexible differential fractal Koch eddy current probe at different excitation freq...This study utilized finite element simulation and experimental methods to investigate the evolution of crack detection performanceof a flexible differential fractal Koch eddy current probe at different excitation frequencies as the lift-off distance increases.As the lift-off distanceincreased,the distribution shape of induced eddy currents changed,leading to reduced similarity in the shape of the excitation coil and an expandeddistribution range of induced eddy currents,ultimately resulting in weakened output signal strength.The experimental results showed that forexcitation frequencies of 10 kHz,20 kHz,50 kHz,100 kHz,200 kHz,500 kHz,and1000 kHz,the maximum lift distances of the real partof the output signal when cracks were detected were 5.0 mm,7.0 mm,8.0 mm,8.0 mm,8.0 mm,6.5 mm,and 4.0 mm,respectively.Theimaginary parts were 6.5 mm,6.5 mm,7.5 mm,5.5 mm,8.0 mm,6.5 mm,and 6.5 mm,respectively.展开更多
目的分析骶髂关节螺钉内固定治疗骨盆后环损伤术后螺钉松动的影响因素。方法回顾性分析2015-07/2023-07月作者医院骨科收治的163例行骶髂关节螺钉内固定手术的患者资料,依据术后是否出现螺钉松动将患者分为螺钉松动组(n=22)和螺钉未松动...目的分析骶髂关节螺钉内固定治疗骨盆后环损伤术后螺钉松动的影响因素。方法回顾性分析2015-07/2023-07月作者医院骨科收治的163例行骶髂关节螺钉内固定手术的患者资料,依据术后是否出现螺钉松动将患者分为螺钉松动组(n=22)和螺钉未松动组(n=141)。比较两组患者的年龄、性别、Young-Burgess分型、Denis分型、螺钉类型、置钉区域、置钉方向、钉道调整次数、亚洲人骨质疏松自我筛查工具(osteoporosis self-assessment tool for Asians,OSTA)指数、骨折复位情况、骨盆前环是否固定以及是否合并新月形骨折情况,并采用多因素Logistic回归分析影响术后螺钉松动的危险因素。结果163例患者均获随访,时间12~48(16.80±6.15)个月。与螺钉未松动组比较,螺钉松动组患者OSTA指数降低,Young-Burgess分型为VS型骨盆骨折、Denis分型累及Ⅱ区、采用普通螺钉、钉道调整次数≥1次的比例更高(P均<0.05)。Logistic回归分析结果显示,Young-Burgess分型为VS骨折、骶骨骨折Denis分型中骨折线累及Ⅱ区、置入普通螺钉、钉道调整次数≥1次以及OSTA指数偏低是骶髂关节螺钉内固定治疗骨盆后环损伤术后螺钉松动的危险因素(P均<0.001)。结论骨盆VS型骨折、骶骨骨折累及DenisⅡ区、术中置入骶髂螺钉较短、钉道调整次数≥1次以及OSTA指数偏低的患者在骶髂关节螺钉内固定治疗骨盆后环损伤术后更容易出现螺钉松动的现象,临床医师应进行术前评估,优化手术技术并加强术后管理以提高骨盆后环损伤患者的预后。展开更多
基金supported by the National Nature Science Foundation of China(Nos.62471206,52467002)。
文摘This study utilized finite element simulation and experimental methods to investigate the evolution of crack detection performanceof a flexible differential fractal Koch eddy current probe at different excitation frequencies as the lift-off distance increases.As the lift-off distanceincreased,the distribution shape of induced eddy currents changed,leading to reduced similarity in the shape of the excitation coil and an expandeddistribution range of induced eddy currents,ultimately resulting in weakened output signal strength.The experimental results showed that forexcitation frequencies of 10 kHz,20 kHz,50 kHz,100 kHz,200 kHz,500 kHz,and1000 kHz,the maximum lift distances of the real partof the output signal when cracks were detected were 5.0 mm,7.0 mm,8.0 mm,8.0 mm,8.0 mm,6.5 mm,and 4.0 mm,respectively.Theimaginary parts were 6.5 mm,6.5 mm,7.5 mm,5.5 mm,8.0 mm,6.5 mm,and 6.5 mm,respectively.
文摘目的分析骶髂关节螺钉内固定治疗骨盆后环损伤术后螺钉松动的影响因素。方法回顾性分析2015-07/2023-07月作者医院骨科收治的163例行骶髂关节螺钉内固定手术的患者资料,依据术后是否出现螺钉松动将患者分为螺钉松动组(n=22)和螺钉未松动组(n=141)。比较两组患者的年龄、性别、Young-Burgess分型、Denis分型、螺钉类型、置钉区域、置钉方向、钉道调整次数、亚洲人骨质疏松自我筛查工具(osteoporosis self-assessment tool for Asians,OSTA)指数、骨折复位情况、骨盆前环是否固定以及是否合并新月形骨折情况,并采用多因素Logistic回归分析影响术后螺钉松动的危险因素。结果163例患者均获随访,时间12~48(16.80±6.15)个月。与螺钉未松动组比较,螺钉松动组患者OSTA指数降低,Young-Burgess分型为VS型骨盆骨折、Denis分型累及Ⅱ区、采用普通螺钉、钉道调整次数≥1次的比例更高(P均<0.05)。Logistic回归分析结果显示,Young-Burgess分型为VS骨折、骶骨骨折Denis分型中骨折线累及Ⅱ区、置入普通螺钉、钉道调整次数≥1次以及OSTA指数偏低是骶髂关节螺钉内固定治疗骨盆后环损伤术后螺钉松动的危险因素(P均<0.001)。结论骨盆VS型骨折、骶骨骨折累及DenisⅡ区、术中置入骶髂螺钉较短、钉道调整次数≥1次以及OSTA指数偏低的患者在骶髂关节螺钉内固定治疗骨盆后环损伤术后更容易出现螺钉松动的现象,临床医师应进行术前评估,优化手术技术并加强术后管理以提高骨盆后环损伤患者的预后。
