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61.
新型可吸收创面止血封固剂对动物体内止血性能的研究   总被引:1,自引:0,他引:1  
目的:研究新型可吸收创面止血封固剂对大鼠肝脏切除创面的止血功效。方法:采用大鼠肝脏切除术,与国外三种创面止血封固剂进行对比试验。结果:(1)新型可吸收创面止血封固剂具有与国外Tachocomb、Gelfix、Surgicel相近的止血速度,在体内24-96小时可完全降解吸收,而且术后各项生化指标、病理检查均无显性差异。(2)良好的亲水性能使其具有较强的粘附力。(3)不含蛋白质对人类各型血液的红细胞不发生凝集反应。(4)具有防止术后粘连的功效。结论:经细胞毒性、遗传毒性、急毒、植入试验等均达到ISO标准,而且新型可吸收创面止血封固剂的价格仅为Tachocomb的5%,可在临床手术中广泛应用。  相似文献   
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Posterior stabilization is a common surgical procedure, which aims for rigid stabilization by facet fusion. Facet non-union has a potential risk of the screw loosening and malalignment. Although some authors have reported the influencing factors about screw loosening in the lumbar spine, there are few reports about the risk factor contributing to the facet non-union in the cervical spine. In all, 22 patients (78 facets and 122 screws) with degenerative cervical kyphosis or spondylolisthesis who underwent decompression and lateral mass screw (LMS) fixation were analyzed. Age, gender, smoking, bone mineral density (BMD), the degree of facet decortication with bone packing, and screw loosening were investigated as risk factors contributing to the facet non-union at each segmental fused level. Facet fusion rate was 85.9% (67/78 facets) and the incidence of loosening was 4.9% (6/122 screws, 4 patients). Insufficient facet decortication with bone packing is a significant risk factor of facet non-union (p <0.05, odds ratio: 26.5). All six loosened screws were associated with bony non-union of the facet and were located in the uppermost or lowermost vertebrae. Comparing loosened screws and stable screws, the average maximal insertional screw torque (MIT) was 9.8 cNm and 39.5 cNm, respectively (p <0.05). Additionally, the length of the stable screws was significantly longer versus the loosened screws (p <0.05). Lower MIT and shorter screw length located near the ends of the lateral mass may predict loosening, which can lead to facet non-union. Sufficient facet decortication with bone packing is one of the important factors contributing to the facet fusion.  相似文献   
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【摘要】 目的:评估寰椎椎弓根螺钉联合经寰枢关节螺钉固定技术的力学稳定性。方法:选取成人颈椎新鲜标本6具,解剖剔除肌肉制备上颈椎完整模型(完整组),用生物力学测试及计算机视觉分析软件测量在1.5Nm力矩下前屈后伸、左右侧弯和左右旋转时C1-C2的活动度(ROM);破坏寰椎前弓和侧块制备不稳模型(失稳组),再次测量相同力矩下各运动方向C1-C2的ROM活动度。随后暴露寰枢椎置钉点,根据先后顺序置入寰椎椎弓根螺钉+枢椎椎弓根螺钉固定(C1P+C2P组)、单纯经寰枢关节螺钉固定(TA组)、寰椎椎弓根螺钉+经寰枢关节螺钉固定(C1P+TA组),依次分别测量相同力矩下各运动方向C1-C2的ROM,比较各组C1-C2 ROM的差异。结果:失稳组相较于完整组在六个方向上有更大的ROM,两组所有方向上的ROM均有显著性差异(P<0.05);C1P+C2P组、C1P+TA组、TA组与失稳组比较,所有方向上的ROM均有显著性减少(P<0.05),三组间比较,前屈、后伸、左旋转和右旋转方向上的ROM存在统计学差异(P<0.05),C1P+TA组相似文献   
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ObjectiveThis study aimed to evaluate the possible effects of surgical procedures on mortality and to identify the possible risk factors for mortality in the management of geriatric hip fractures.MethodsA total of 191 patients (105 women and 86 men; mean age 82.26±9.681 [60–108] years) with AO/OTA 31A2.2 intertrochanteric fractures and treated with sliding hip screw, proximal femoral nail, or hemiarthroplasty were included in this retrospective cohort study. The treatment type was decided by the responsible surgeon according to the patients’ pre-injury activity level, bone quality, and features of the fracture. Age, sex, type of fracture, type of surgery performed, American society of anesthesiology (ASA) grade, type of anesthesia, time to surgery, type of physical therapy, length of hospital stay, and number of comorbidities were documented. We evaluated the 30-day and 1-year mortality of patients treated with sliding hip screw (SHS), proximal femoral nail antirotation (PFN-A), or hemiarthroplasty and identified the possible risk factors for mortality.ResultsA total of 49 patients underwent SHS, 58 underwent PFN-A, and 84 underwent hemiarthroplasty. Of these, 2 patients with SHS, 2 with PFN-A, and 11 with hemiarthroplasty died within 30 days after surgery, whereas 7 patients with SHS, 15 with PFN-A, and 23 with hemiarthroplasty died 1 year after surgery. The 30-day and 1-year overall mortality rates were 7.9% and 23.6%, respectively. Both the 30-day and 1-year mortality risks were higher in patients undergoing hemiarthroplasty than in patients undergoing SHS (p=0.068 versus 0.058). The 30-day mortality was higher in patients receiving general anesthesia than in those receiving combined spinal and epidural anesthesia (p=0.009). The 1-year mortality risk was higher in patients with ASA grade 4 than in those with grade 1 and 2 (p=0.045). Advanced age (p=0.022) and male sex (p=0.007) were also found to be the risk factors for 1-year mortality.ConclusionWe demonstrated that higher ASA grade, male sex, general anesthesia, and hemiarthroplasty procedures are associated with higher mortality rates in elderly patients with hip fractures. Thus, we highly recommend orthopedic surgeons to consider all these factors in the management of intertrochanteric hip fractures in the geriatric population.Level of EvidenceLevel IV, Prognostic Study  相似文献   
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PurposeThis study aimed to compare the efficacy of decreasing leg-length discrepancy (LLD) and postoperative complications between tension band plates (TBP) and percutaneous transphyseal screws (PETS).MethodsThis retrospective study reviewed LLD patients who underwent temporary epiphysiodesis at the distal femur and/or proximal tibia from 2010 to 2017 (minimum two years follow-up). Efficacy of decreasing LLD was assessed one and two years postoperatively. Complications were classified with the modified Clavien-Dindo-Sink complication classification system. Knee deformities were assessed by percentile and zone of mechanical axis across the tibial plateau.ResultsIn total, 53 patients (25 boys, 28 girls) underwent temporary epiphysiodesis (mean age, 11.4 years). The efficacy of decreasing LLD at two years between the TBP (n = 38) and PETS (n = 15) groups was comparable. Seven grade III complications were recorded in six TBP patients and in one PETS patient who underwent revision surgeries for knee deformities and physis impingement. Four grade I and two grade II complications occurred in the TBP group. The mechanical axis of the leg shifted laterally in the PETS group and medially in the TBP groups (+7.1 percentile versus -4.2 percentile; p < 0.05). Shifting of the mechanical axis by two zones was noted medially in four TBP patients and laterally in two PETS patients.ConclusionMore implant-related complications and revision surgeries for angular deformities were associated with TBP. A tendency of varus and valgus deformity after epiphysiodesis using TBP and PETS was observed, respectively. Patients and families should be informed of the risks and regular postoperative follow-up is recommended.Level of evidenceLevel III  相似文献   
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针对髋臼前后柱置钉通道多截面调控规划法的不足,该研究提出了基于大密度点云数据、相关理论、软件内置功能及自编程序的规划方法,实现了对置钉通道总长的全局优化,同时进行了基于7截面、11截面调控规划法以及点云数据的前柱最大内接圆柱体虚拟置钉实验,分析了实验结果及形成机理,验证了基于点云数据规划法的全局优化效果,但对多截面调控规划法的调控有效性表示还存有疑问,此外,还对基于点云数据的髋臼置钉通道规划方法应用的相关原理和操作技巧作了简略介绍。  相似文献   
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目的:探讨3D打印导航模板辅助椎弓根螺钉在脊柱侧弯矫形术中的置钉效果。方法:回顾性分析2018年1月至2020年6月间采用椎弓根螺钉置钉法治疗的39例脊柱侧弯患者的病例资料,其中采用3D打印导航模板辅助置钉(3D组)18例,常规徒手置钉方法置钉(徒手组)21例。记录并比较2组的置钉时间、置钉出血量、置钉透视次数、置钉等级及准确率、置钉可接受率、置钉并发症和主弯矫形率。采用SPSS 19.0软件进行统计学分析。结果:39例患者均顺利完成术中置钉,术后徒手组4例出现并发症,治疗后症状消失,3D组无相关并发症出现。3D组的置钉时间、置钉出血量、置钉透视次数少于徒手组,置钉等级及准确率、置钉可接受率均优于徒手组,差异有统计学意义(P<0.05);3D组和徒手组主弯矫形率比较差异无统计学意义(P>0.05)。结论:在脊柱侧弯矫形术中采用3D打印导航模板辅助椎弓根螺钉置钉,可显著降低置钉难度、优化术中置钉操作、提升置钉效果,是一种较好的置钉方法。  相似文献   
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