目的:探讨弯钳撬拔术在股骨近端髓内钉(proximal femoral nail antirotation,PFNA)内固定治疗难复性股骨粗隆间骨折中的应用效果。方法:选择2021年6月—2023年5月在罗定市中医院接受手术治疗的难复性股骨粗隆间骨折患者144例,用随机数...目的:探讨弯钳撬拔术在股骨近端髓内钉(proximal femoral nail antirotation,PFNA)内固定治疗难复性股骨粗隆间骨折中的应用效果。方法:选择2021年6月—2023年5月在罗定市中医院接受手术治疗的难复性股骨粗隆间骨折患者144例,用随机数字表法将患者分为对照组(n=72,接受切开复位PFNA内固定治疗)、观察组(n=72,接受弯钳撬拔PFNA内固定治疗)。对比两组手术基本情况、骨折愈合情况、髋关节功能评分、并发症发生情况。结果:两组手术时间比较,差异无统计学意义(P>0.05);观察组术中出血量较对照组少,差异有统计学意义(P<0.05)。观察组术后住院时间、负重开始时间、骨折愈合时间均较对照组短,差异均有统计学意义(P<0.05)。术后6个月,观察组髋关节功能评分较对照组高,差异有统计学意义(P<0.05)。两组术后6个月的髋关节功能优良率比较,差异无统计学意义(P>0.05)。两组并发症发生率比较,差异无统计学意义(P>0.05)。结论:弯钳撬拔PFNA内固定治疗难复性股骨粗隆间骨折较切开复位PFNA内固定治疗更具优势,在促进术后骨折愈合、恢复患侧髋关节功能方面的作用均较理想,且不会增加并发症,是一种优质的手术模式。展开更多
This study presents and verifies a new idea for constructing a rotary traveling wave ultrasonic motor （USM） that uses the radial bending mode of a ring. In the new design, 20 trapezoid cross section slots are cut sy...This study presents and verifies a new idea for constructing a rotary traveling wave ultrasonic motor （USM） that uses the radial bending mode of a ring. In the new design, 20 trapezoid cross section slots are cut symmetrically in the outer surface of a thick duralumin alloy ring, where 20 PZT stacks are nested. In each slot, two wedging blocks are set between the PZT stack and the two sides of the slot respectively to apply preloading on the PZT ceramics. Two radial bending modes of the stator that have a phase difference of a quarter wavelength on space are generated by using the d33 operating mode of the PZT elements, and then a flexural traveling wave is formed by the superimposing of two standing waves whose amplitudes are equal and phases are different by 90~ temporally. Two conical rotors are pressed to each end of the ring type stator by a coiled spring. The finite element method （FEM） simulation is developed to validate the feasibility of the proposed motor. The maximal speed and torque of the prototype are tested to be 126 r/rain and 0.8 N＇m, respectively.展开更多
文摘目的:探讨弯钳撬拔术在股骨近端髓内钉(proximal femoral nail antirotation,PFNA)内固定治疗难复性股骨粗隆间骨折中的应用效果。方法:选择2021年6月—2023年5月在罗定市中医院接受手术治疗的难复性股骨粗隆间骨折患者144例,用随机数字表法将患者分为对照组(n=72,接受切开复位PFNA内固定治疗)、观察组(n=72,接受弯钳撬拔PFNA内固定治疗)。对比两组手术基本情况、骨折愈合情况、髋关节功能评分、并发症发生情况。结果:两组手术时间比较,差异无统计学意义(P>0.05);观察组术中出血量较对照组少,差异有统计学意义(P<0.05)。观察组术后住院时间、负重开始时间、骨折愈合时间均较对照组短,差异均有统计学意义(P<0.05)。术后6个月,观察组髋关节功能评分较对照组高,差异有统计学意义(P<0.05)。两组术后6个月的髋关节功能优良率比较,差异无统计学意义(P>0.05)。两组并发症发生率比较,差异无统计学意义(P>0.05)。结论:弯钳撬拔PFNA内固定治疗难复性股骨粗隆间骨折较切开复位PFNA内固定治疗更具优势,在促进术后骨折愈合、恢复患侧髋关节功能方面的作用均较理想,且不会增加并发症,是一种优质的手术模式。
基金Project supported by the National Natural Science Foundation of China (Nos. 50875057 and 51105097)the State Key Laboratory of Robotics and Systems (No. SKLRS200901A04), China
文摘This study presents and verifies a new idea for constructing a rotary traveling wave ultrasonic motor （USM） that uses the radial bending mode of a ring. In the new design, 20 trapezoid cross section slots are cut symmetrically in the outer surface of a thick duralumin alloy ring, where 20 PZT stacks are nested. In each slot, two wedging blocks are set between the PZT stack and the two sides of the slot respectively to apply preloading on the PZT ceramics. Two radial bending modes of the stator that have a phase difference of a quarter wavelength on space are generated by using the d33 operating mode of the PZT elements, and then a flexural traveling wave is formed by the superimposing of two standing waves whose amplitudes are equal and phases are different by 90~ temporally. Two conical rotors are pressed to each end of the ring type stator by a coiled spring. The finite element method （FEM） simulation is developed to validate the feasibility of the proposed motor. The maximal speed and torque of the prototype are tested to be 126 r/rain and 0.8 N＇m, respectively.
