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71.
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   
72.
【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   
73.
目的:评估一期前路病灶清除联合后路经S2骶髂关节螺钉内固定治疗腰骶椎感染的疗效。方法:回顾性分析2016年1月~2018年1月因腰骶椎感染行一期前路病灶清除联合后路经S2骶髂关节(second sacral alar-iliac,S2AI)螺钉内固定患者10例,男7例,女3例;年龄50~75岁,平均61.8±7.7岁。10例患者均系自发感染,其中3例合并糖尿病。所有患者均排除结核、布氏杆菌感染。所有患者术前完善白细胞计数、红细胞沉降率(erythrocyte sedimentation rate,ESR)以及C-反应蛋白(C-reactive protein,CRP)等检查。术前根据细菌培养及药敏试验结果应用抗生素。术后继续使用敏感抗生素,监测白细胞计数、ESR以及CRP以指导抗生素使用。记录手术时间、术中出血量、术前腰背痛视觉模拟评分(visual analogue scale,VAS)、术前腰椎JOA评分、末次随访VAS评分及JOA评分。影像学随访观察内固定及植骨融合情况。结果:10例患者均顺利完成手术,手术时间165~225min,平均193.5±20.6min,术中出血量为200~450ml,平均310.0±81.0ml。手术切口一期愈合。抗生素使用时间83~97d,平均89.2±4.5d。术后3个月时所有患者白细胞计数、ESR及CRP均降至正常。随访期间未发现感染复发的患者。腰背痛VAS评分由术前6.4±1.0分降至末次随访时的1.4±1.0分(P0.05),JOA评分由术前14.4±2.8分上升至末次随访时的24.3±2.9分(P0.05)。末次随访时,所有病例内固定位置良好,植骨区融合良好。结论:一期前路病灶清除联合后路S2AI螺钉固定治疗腰骶椎感染,可获得坚强的固定和满意的疗效。  相似文献   
74.
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   
75.
76.
目的探讨肝包虫囊肿压迫下腔静脉的外科治疗。方法采用回顾性描述性研究方法。收集2013年5月至2018年5月石河子大学医学院第一附属医院收治的10例肝包虫囊肿压迫下腔静脉病人的临床资料;男7例,女3例;年龄为(46±5)岁,年龄范围为38~51岁。根据术中肝包虫囊肿与下腔静脉的贴合程度以及囊肿完整切除的难易程度,分别行外膜内外囊完整切除术、外膜内外囊次全切除术、外膜内外囊完整切除联合下腔静脉部分切除术。观察指标:(1)手术情况。(2)术后情况。(3)随访情况。采用门诊和电话方式进行随访,于术后3、6、12、24个月门诊随访1次。行彩色多普勒超声检查了解病人肝包虫囊肿复发及下腔静脉栓塞情况。随访终点为术后2年,随访次要终点为肝包虫囊肿复发。随访时间截至2020年5月。正态分布的计量资料以x±s表示。计数资料以绝对数表示。结果(1)手术情况:10例病人均顺利完成手术,7例行外膜内外囊完整切除术,2例行外膜内外囊次全切除术,1例行外膜内外囊完整切除联合下腔静脉部分切除术。10例病人术中无大出血及感染性休克发生。10例病人手术时间为(99±27)min;术中出血量为(99±48)mL。(2)术后情况:10例病人术后2~5 d拔除引流管,无术后出血、术后残腔感染、术后胆瘘发生,无围术期死亡病人,术后住院时间为(7.1±1.8)d。(3)随访情况:10例病人中,9例完成终点随访,随访时间内均无肝包虫囊肿复发及下腔静脉栓塞形成;1例病人于术后12个月,第3次随访失访,此病人术后3、6个月随访未发现肝包虫囊肿复发及下腔静脉栓塞。结论外膜内外囊完整切除术、外膜内外囊次全切除术、外膜内外囊完整切除联合下腔静脉部分切除术均能完整切除肝包虫囊肿。  相似文献   
77.
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   
78.
BackgroudThe purpose of this study was to investigate the characteristics of osteoporotic vertebral compression fractures (OVCFs) in Korean postmenopausal women and the association between OVCFs and clinical factors such as age, bone mineral density (BMD), and quality of life.MethodsAccording to the population distribution in four regions in Korea, 1,281 postmenopausal female patients were recruited from nationwide orthopedic outpatient clinics. Radiologic, asymptomatic, and within 3 months of OVCF groups were analyzed based on age, fracture location, and prevalence according to BMD. In addition, BMD, T-score, body mass index, and European Quality of Life-5 Dimensions (EQ-5D) were investigated in the three groups, and the differences between groups were compared and analyzed.ResultsThe prevalence of radiologic OVCFs at the T11–L1 was 3.7 times higher in the 70s group (44.0%) than in the 50s group (11.9%). Femur and total hip BMD were significantly lower in patients with thoracolumbar junction fractures than in patients with L2–5 fractures, whereas no difference was observed in lumbar spine BMD. Of the three OVCF groups, the within 3 months of OVCF group had the lowest lumbar spine T-score of −2.445. The asymptomatic OVCF group also showed significantly lower lumbar spine T-score than did the group without radiologic OVCFs (p < 0.001). The EQ-5D showed a significant decrease in the radiologic OVCF group (p < 0.001) and within 3 months of OVCF group (p < 0.001).ConclusionsThe prevalence of OVCFs in the thoracolumbar junction rapidly increases with old age and low BMD in Korean postmenopausal women. Femur and total hip BMD are more predictive of thoracolumbar junction fractures than lumbar spine BMD. Patients with radiologic OVCFs had a significantly lower quality of life than no OVCF group. Therefore, this study shows it is important to treat and prevent osteoporosis before an OVCF occurs.  相似文献   
79.
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   
80.
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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