目的:经皮椎体后凸成形术(PKP)对骨质疏松性椎体压缩性骨折(OVCF)患者脊柱-骨盆矢状面参数及继发邻椎骨折的影响。方法:选取112例OVCF患者为研究对象,根据手术方式不同分为PVP组[椎体成形术(PVP)治疗]和PKP组(PKP治疗),每组各56例。比...目的:经皮椎体后凸成形术(PKP)对骨质疏松性椎体压缩性骨折(OVCF)患者脊柱-骨盆矢状面参数及继发邻椎骨折的影响。方法:选取112例OVCF患者为研究对象,根据手术方式不同分为PVP组[椎体成形术(PVP)治疗]和PKP组(PKP治疗),每组各56例。比较两组患者围手术期指标(骨水泥量、手术时间及住院时间)、并发症(骨水泥渗漏、术后感染)发生情况、术前及术后6个月疼痛程度[视觉模拟疼痛量表(VAS)评分]、日常生活功能障碍[功能障碍指数问卷表(ODI)评分]、影像学参数[胸椎后凸角(TK)、骨盆倾斜角(PT)、腰椎前凸角(LL)、骶骨倾斜角(SS)、骨盆入射角(PI)、脊柱骶骨角(SSA)]及继发骨折情况。结果:PKP组患者使用骨水泥量、手术时间高于PVP组(P<0.05)。两组患者并发症发生率差异无统计学意义(P>0.05)。术后7 d、6个月,两组患者VAS评分、ODI评分均逐渐降低(P<0.05),且术后7 d PKP组低于PVP组(P<0.05);术后6个月,两组TK均降低(P<0.05),LL、PT、SSA均升高(P<0.05),且术后6个月两组患者TK、LL差异有统计学意义(P<0.05)。两组患者继发骨折率差异无统计学意义(P>0.05)。结论:相较于PVP,PKP治疗OVCF手术时间较长,但可有效减轻患者术后疼痛,改善术后日常活动功能障碍,有利于改善脊柱矢状面平衡,值得临床推广。展开更多
Crushing and embedment are two critical downhole proppant degradation mechanisms that lead to a significant drop in production outputs in unconventional oil/gas stimulation projects. These persistent production drops ...Crushing and embedment are two critical downhole proppant degradation mechanisms that lead to a significant drop in production outputs in unconventional oil/gas stimulation projects. These persistent production drops due to the non-linear responses of proppants under reservoir conditions put the future utilization of such advanced stimulation techniques in unconventional energy extraction in doubt. The aim of this study is to address these issues by conducting a comprehensive experimental approach. According to the results, whatever the type of proppant, all proppant packs tend to undergo significant plastic deformation under the first loading cycle.Moreover, the utilization of ceramic proppants(which retain proppant pack porosity up to 75%), larger proppant sizes(which retain proppant pack porosity up to 15.2%) and higher proppant concentrations(which retain proppant pack porosity up to 29.5%) in the fracturing stimulations with higher in-situ stresses are recommended to de-escalate the critical consequences of crushing associated issues. Similarly, the selection of resin-coated proppants over ceramic and sand proppants may benefit in terms of obtaining reduced proppant embedment.In addition, selection of smaller proppant sizes and higher proppant concentrations are suggested for stimulation projects at depth with sedimentary formations and lower in-situ stresses where proppant embedment predominates. Furthermore, correlation between proppant embedment with repetitive loading cycles was studied.Importantly, microstructural analysis of the proppant-embedded siltstone rock samples revealed that the initiation of secondary induced fractures. Finally, the findings of this study can greatly contribute to accurately select optimum proppant properties(proppant type, size and concentration) depending on the oil/gas reservoir characteristics to minimize proppant crushing and embedment effects.展开更多
文摘目的:经皮椎体后凸成形术(PKP)对骨质疏松性椎体压缩性骨折(OVCF)患者脊柱-骨盆矢状面参数及继发邻椎骨折的影响。方法:选取112例OVCF患者为研究对象,根据手术方式不同分为PVP组[椎体成形术(PVP)治疗]和PKP组(PKP治疗),每组各56例。比较两组患者围手术期指标(骨水泥量、手术时间及住院时间)、并发症(骨水泥渗漏、术后感染)发生情况、术前及术后6个月疼痛程度[视觉模拟疼痛量表(VAS)评分]、日常生活功能障碍[功能障碍指数问卷表(ODI)评分]、影像学参数[胸椎后凸角(TK)、骨盆倾斜角(PT)、腰椎前凸角(LL)、骶骨倾斜角(SS)、骨盆入射角(PI)、脊柱骶骨角(SSA)]及继发骨折情况。结果:PKP组患者使用骨水泥量、手术时间高于PVP组(P<0.05)。两组患者并发症发生率差异无统计学意义(P>0.05)。术后7 d、6个月,两组患者VAS评分、ODI评分均逐渐降低(P<0.05),且术后7 d PKP组低于PVP组(P<0.05);术后6个月,两组TK均降低(P<0.05),LL、PT、SSA均升高(P<0.05),且术后6个月两组患者TK、LL差异有统计学意义(P<0.05)。两组患者继发骨折率差异无统计学意义(P>0.05)。结论:相较于PVP,PKP治疗OVCF手术时间较长,但可有效减轻患者术后疼痛,改善术后日常活动功能障碍,有利于改善脊柱矢状面平衡,值得临床推广。
文摘Crushing and embedment are two critical downhole proppant degradation mechanisms that lead to a significant drop in production outputs in unconventional oil/gas stimulation projects. These persistent production drops due to the non-linear responses of proppants under reservoir conditions put the future utilization of such advanced stimulation techniques in unconventional energy extraction in doubt. The aim of this study is to address these issues by conducting a comprehensive experimental approach. According to the results, whatever the type of proppant, all proppant packs tend to undergo significant plastic deformation under the first loading cycle.Moreover, the utilization of ceramic proppants(which retain proppant pack porosity up to 75%), larger proppant sizes(which retain proppant pack porosity up to 15.2%) and higher proppant concentrations(which retain proppant pack porosity up to 29.5%) in the fracturing stimulations with higher in-situ stresses are recommended to de-escalate the critical consequences of crushing associated issues. Similarly, the selection of resin-coated proppants over ceramic and sand proppants may benefit in terms of obtaining reduced proppant embedment.In addition, selection of smaller proppant sizes and higher proppant concentrations are suggested for stimulation projects at depth with sedimentary formations and lower in-situ stresses where proppant embedment predominates. Furthermore, correlation between proppant embedment with repetitive loading cycles was studied.Importantly, microstructural analysis of the proppant-embedded siltstone rock samples revealed that the initiation of secondary induced fractures. Finally, the findings of this study can greatly contribute to accurately select optimum proppant properties(proppant type, size and concentration) depending on the oil/gas reservoir characteristics to minimize proppant crushing and embedment effects.
