BACKGROUND The volar approach with plate fixation is the gold standard for treating distal radius fractures,often requiring incision of the pronator quadratus(PQ)muscle.Preserving the PQ during surgery may facilitate ...BACKGROUND The volar approach with plate fixation is the gold standard for treating distal radius fractures,often requiring incision of the pronator quadratus(PQ)muscle.Preserving the PQ during surgery may facilitate early postoperative recovery.However,conventional minimally invasive plate osteosynthesis(MIPO)techniques frequently necessitate multiple(3-4)intraoperative fluoroscopic adjustments to achieve optimal plate positioning,which can inadvertently damage the PQ muscle.Based on our clinical observations,we developed a novel 3-point positioning technique to minimize PQ injury while ensuring accurate plate placement.Preliminary results demonstrate promising early clinical outcomes.AIM To retrospectively analyze distal radius fractures treated using the 3-point positioning-assisted MIPO technique with preservation of the PQ.METHODS The 3-point positioning technique was applied:The Kirschner wire was inserted after fluoroscopy and was correctly adjusted the position of the plate above the PQ.With the aid of Kirschner wires positioning the PQ stripping was performed only once,and the plate then placed in a correct and satisfactory position.Operation time,incision length,wrist pain score,upper extremity function disabilities of the arm,shoulder and hand(DASH)score,wrist Gartland-Werley score,wrist grip strength,and range of motion were among the quantitative variables recorded.Qualitative variables including AO fracture classification,intraoperative and postoperative complications were evaluated.RESULTS At a mean follow-up of 6.9±0.8 months,the mean scar length was 25.4±1.5 mm,the pain score was 0.7±0.6,the DASH score for the upper limb was 4.7±1.3,and the Gartland-Werley score for wrist function was 4.1±1.1 at the last follow-up.Mean flexion was 97.3%,extension was 97.0%,pronation was 98.9%,supination was 98.9%,and grip strength was 86.6%compared to contralateral values.No unfavorable intraoperative or postoperative complications occurred.CONCLUSION The 3-point positioning technique may reduce the damage to the PQ muscle and is a safe and effective method for MIPO for distal radius fractures.展开更多
近年来北斗2号卫星导航接收机在军民用领域得到广泛应用。随着北斗3号卫星导航系统的不断发展和完善,北斗3号单模多频点卫星导航接收机的研制成为北斗卫星导航领域重要研究方向之一。结合北斗3号卫星导航系统不同频点卫星信号特点,从工...近年来北斗2号卫星导航接收机在军民用领域得到广泛应用。随着北斗3号卫星导航系统的不断发展和完善,北斗3号单模多频点卫星导航接收机的研制成为北斗卫星导航领域重要研究方向之一。结合北斗3号卫星导航系统不同频点卫星信号特点,从工程实际应用的角度出发,设计了一种基于FPGA(field-programmable gate array)+DSP(digital signal processing)架构的北斗3号单模多频点卫星导航接收机。通过对接收机总体架构进行设计,详细阐述了不同频点卫星信号射频模块、基带信号捕获跟踪模块、导航定位解算模块的机理,设计了对应的北斗3号卫星导航接收机硬件驱动电路。最后,通过卫星导航信号模拟器端设置静态、高动态定位场景,验证设计方案的可行性。试验结果表明,设计并实现的接收机能够满足技术指标要求,进一步验证了本文提出方案的有效性。展开更多
随着全球导航卫星系统技术的发展,广播星历精度逐渐提升,为基于广播星历实现的精密单点定位(precise point position with broadcast ephemerides, BE-PPP)带来了希望。本文基于2022年6月至2023年11月的BDS-3广播星历分析了其误差特性,...随着全球导航卫星系统技术的发展,广播星历精度逐渐提升,为基于广播星历实现的精密单点定位(precise point position with broadcast ephemerides, BE-PPP)带来了希望。本文基于2022年6月至2023年11月的BDS-3广播星历分析了其误差特性,并基于此改正相应误差实现BDS-3 BE-PPP。根据实验结果,本文首次发现BDS-3广播和精密轨道间的赫尔默特旋转参数在2023年8月逐渐减小,这也改善了赫尔默特七参数的根和平方(root-sum-square,RSS)。2023年9月、10月和11月的RSS平均值分别为5.16 cm、5.51 cm和5.12 cm,明显优于其余月份。通过修正BDS-3广播轨道Z向年周期平移误差和引入广播星历视线方向综合误差参数进行BE-PPP数据处理,2月的静态和仿动态的三维定位精度分别为32.6 cm和52.5 cm;11月使用精度提升的BDS-3广播星历的静态和仿动态的三维定位精度分别为26.6cm和43.5cm,相比2月,分别提升了18.4%和15.5%。展开更多
基金Supported by Fujian Provincial Clinical Medical Research Center for First Aid and Rehabilitation in Orthopaedic Trauma,No.2020Y2014Fuzhou Health Technology Innovation Platform Construction Project,No.2019-S-wp2.
文摘BACKGROUND The volar approach with plate fixation is the gold standard for treating distal radius fractures,often requiring incision of the pronator quadratus(PQ)muscle.Preserving the PQ during surgery may facilitate early postoperative recovery.However,conventional minimally invasive plate osteosynthesis(MIPO)techniques frequently necessitate multiple(3-4)intraoperative fluoroscopic adjustments to achieve optimal plate positioning,which can inadvertently damage the PQ muscle.Based on our clinical observations,we developed a novel 3-point positioning technique to minimize PQ injury while ensuring accurate plate placement.Preliminary results demonstrate promising early clinical outcomes.AIM To retrospectively analyze distal radius fractures treated using the 3-point positioning-assisted MIPO technique with preservation of the PQ.METHODS The 3-point positioning technique was applied:The Kirschner wire was inserted after fluoroscopy and was correctly adjusted the position of the plate above the PQ.With the aid of Kirschner wires positioning the PQ stripping was performed only once,and the plate then placed in a correct and satisfactory position.Operation time,incision length,wrist pain score,upper extremity function disabilities of the arm,shoulder and hand(DASH)score,wrist Gartland-Werley score,wrist grip strength,and range of motion were among the quantitative variables recorded.Qualitative variables including AO fracture classification,intraoperative and postoperative complications were evaluated.RESULTS At a mean follow-up of 6.9±0.8 months,the mean scar length was 25.4±1.5 mm,the pain score was 0.7±0.6,the DASH score for the upper limb was 4.7±1.3,and the Gartland-Werley score for wrist function was 4.1±1.1 at the last follow-up.Mean flexion was 97.3%,extension was 97.0%,pronation was 98.9%,supination was 98.9%,and grip strength was 86.6%compared to contralateral values.No unfavorable intraoperative or postoperative complications occurred.CONCLUSION The 3-point positioning technique may reduce the damage to the PQ muscle and is a safe and effective method for MIPO for distal radius fractures.
文摘北斗三号卫星导航系统(BeiDou-3 Navigation Satellite System,BDS-3)于2020年7月正式开通全球导航定位服务.目前,BDS-3在B1I、B3I、B1C、B2a和B2b频点提供公开服务.伪距单点定位(single point positioning,SPP)因其成本低、算法简单等特点,广泛应用于车辆导航与智能终端定位等领域.为系统评估BDS-3各频点单频SPP性能,并探究北斗全球电离层延迟修正模型(BDS global ionospheric model,BDGIM)的性能,本文构建了适用于BDS-3全频点的单频SPP模型,基于22个全球均匀分布测站的观测数据,对比分析了BDGIM与GPS Klobuchar模型(GPSK8)在太阳活动活跃期与平静期对定位精度的影响.实验结果表明,在全球尺度上,BDGIM性能总体优于GPSK8,在平静期和活跃期的定位精度提升分别为15.6%和11.5%,且在高、低纬度地区改善尤为显著.各频点的单频SPP结果显示,B1C和B1I定位性能最优,3D方向精度分别为3.31 m和3.39 m.
文摘近年来北斗2号卫星导航接收机在军民用领域得到广泛应用。随着北斗3号卫星导航系统的不断发展和完善,北斗3号单模多频点卫星导航接收机的研制成为北斗卫星导航领域重要研究方向之一。结合北斗3号卫星导航系统不同频点卫星信号特点,从工程实际应用的角度出发,设计了一种基于FPGA(field-programmable gate array)+DSP(digital signal processing)架构的北斗3号单模多频点卫星导航接收机。通过对接收机总体架构进行设计,详细阐述了不同频点卫星信号射频模块、基带信号捕获跟踪模块、导航定位解算模块的机理,设计了对应的北斗3号卫星导航接收机硬件驱动电路。最后,通过卫星导航信号模拟器端设置静态、高动态定位场景,验证设计方案的可行性。试验结果表明,设计并实现的接收机能够满足技术指标要求,进一步验证了本文提出方案的有效性。
文摘随着全球导航卫星系统技术的发展,广播星历精度逐渐提升,为基于广播星历实现的精密单点定位(precise point position with broadcast ephemerides, BE-PPP)带来了希望。本文基于2022年6月至2023年11月的BDS-3广播星历分析了其误差特性,并基于此改正相应误差实现BDS-3 BE-PPP。根据实验结果,本文首次发现BDS-3广播和精密轨道间的赫尔默特旋转参数在2023年8月逐渐减小,这也改善了赫尔默特七参数的根和平方(root-sum-square,RSS)。2023年9月、10月和11月的RSS平均值分别为5.16 cm、5.51 cm和5.12 cm,明显优于其余月份。通过修正BDS-3广播轨道Z向年周期平移误差和引入广播星历视线方向综合误差参数进行BE-PPP数据处理,2月的静态和仿动态的三维定位精度分别为32.6 cm和52.5 cm;11月使用精度提升的BDS-3广播星历的静态和仿动态的三维定位精度分别为26.6cm和43.5cm,相比2月,分别提升了18.4%和15.5%。
