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61.
目的:探讨脊柱-骨盆矢状位参数及关节突关节角度对退变性腰椎滑脱的影响及相关性研究。方法:以2016年7月至2019年9月确诊的120例L4-L5单节段退变性滑脱患者为观察对象(滑脱组),以性别和年龄相匹配的120例L4-L5节段退变性椎管狭窄患者为对照(对照组)。通过影像学资料测量如下参数:骨盆入射角(pelvic incidence,PI),骨盆倾斜角(pelvic tilt,PT),骶骨倾斜角(sacral slope,SS),腰椎前凸(lumbar lordosis,LL),胸椎后凸(thoracic kyphosis,TK),矢状面平衡(sagittal vertical axis,SVA),L4-L5头侧关节突关节角,尾侧关节突关节角及小关节不对称性。比较两组患者参数的差异并对有意义参数行Logistic回归分析。对退变性腰椎滑脱患者关节突关节方向与脊柱-骨盆参数进行相关性分析。结果:两组患者在PI、PT、LL、SVA、头侧关节突关节角、尾侧关节突关节角差异有统计学意义(P<0.05);Logistic回归分析发现PI、PT及头侧关节突关节角是腰椎滑脱程度的危险因素(P<0.05)。滑脱组头侧关节突关节矢状化与PI、PT呈现显著相关(P<0.05)。结论:高PI、PT及头侧关节突关节矢状化是腰椎滑脱的危险因素,并且关节突关节矢状化程度和大PI、PT密切相关。 相似文献
62.
63.
Christopher G. Lenz Richard Niehaus Ivo Knych Karim Eid Paul Borbas 《Foot and Ankle Surgery》2021,27(1):20-24
BackgroundScarf osteotomy has been widely used to restore axial orientation of the first ray in the treatment of hallux valgus deformity. The aim of the study was to present our radiological outcomes of bunion reconstruction, identify surgical complications in early follow-up, and assess to what extent a shortening of the first metatarsal is present after surgery as a possible cause of postoperative metatarsalgia.MethodsWe enrolled 106 patients (118 feet) and assessed patients’ pre- and postoperative measurements of hallux valgus and intermetatarsal angles on weightbearing X-ray images. Three different methods of measuring metatarsal length were compared and early postoperative complications noted.ResultsHallux valgus angle decreased significantly by an average of 18.7 degrees and the intermetatarsal angle by 7.8 degrees. Using three methods of measuring metatarsal length, all showed significant shortening of the first metatarsal. Mean relative lengthening of the second metatarsal averaged 0.45 mm. The Coughlin method showed the highest interrater reliability (ICC = 0.96).ConclusionsSignificant reduction of the hallux valgus angle and intermetatarsal angle was demonstrated with a low complication rate. There was significant shortening of the first metatarsal. The Coughlin method clearly demonstrated an excellent interrater reliability.Level of evidenceLevel IV. 相似文献
64.
Jian Qian Qian Zhang Qiang Cao Jie Jiang Pu Li Meiling Bao Chao Qin Zengjun Wang Lixin Hua Pengfei Shao 《Translational andrology and urology》2021,10(3):1030
BackgroundThis study investigated a comfortable suture angle (CSA) with optimized trocar position for closing the defect during renorrhaphy in retroperitoneal laparoscopic partial nephrectomy (LPN). The feasibility, usefulness, and safety of achieving the CSA with modified trocar position were determined for different tumor types.MethodsTwo optimized trocar positions were introduced for different tumor types. A suture angle was based on the tumor plane of the superficial parenchyma defect and the line formed by the needle holder. Preliminary surgical simulations determined a CSA that combined the least suture time with the greatest ease of performance. Achieving the CSA was attempted during renorrhaphy of 106 enrolled patients undergoing retroperitoneal LPN. Patients’ characteristics, operative features, and follow-up information were collected and analyzed.ResultsFor 89 (83.96%) patients, a CSA was successfully reached and parenchyma recovered. The remaining 17 patients were successfully sutured, but the attempt to achieve a CSA failed. For the CSA group, the suture, clamping, and overall operative times were significantly less than that of the non-CSA patients. The groups were similar regarding estimated blood loss, positive surgical margin, and rates of glomerular filtration reduction and complications. Univariable analyses determined that tumor location, growth pattern, and R.E.N.A.L. nephrometry score (RNS) may influence the success of this approach. Multivariable analyses indicated that only tumor location and RNS were independent factors affecting successful achievement of the CSA.ConclusionsThrough different kidney position changes, the CSA could be used to ease the suture process. It is feasible and safe to perform a CSA with optimized trocar position during LPN. Tumor location and RNS may influence the approach to get a CSA. 相似文献
65.
Introduction and importanceWilkie’s syndrome[SMA(Superior Mesenteric Artery) syndrome or Cast syndrome]) is a unique and rare presentation which may be included in the differential diagnosis especially when a Gastric outlet obstruction is being investigated and there is a history of an associated element of rapid weight loss. The purpose of presenting this case report is its uniqueness given a history of intermittent fasting rather than the usual eating disorders.Case presentationA crescendo worsening of symptoms of intractable vomiting, inability to eat, upper abdominal gas bloating and post meal abdominal pain since one week in a patient during a period of fasting for the first time had been observed.Clinical discussionAfter initial resuscitation, an ultrasound abdomen and an abdominal x ray revealed a distended stomach and a nasogastric tube was immediately introduced to avoid aspiration. A CT scan of the abdomen with contrast revealed the compressed duodenum in the aortomesenteric angle and the diagnosis of SMA syndrome was confirmed. An upper gastrointestinal endoscopy was also done to rule out other causes and it was found to be normal.ConclusionIn an acute presentation, the response to conservative management is remarkable and in the absence of any possible future reoccurrences the surgical options may be avoided. High index of suspicion, appropriate radiological diagnosis and stepwise treatment options may guide the troubled patient towards recovery in this rare presentation. A proper history taking is key in diagnosing such a condition and does not have to be limited to eating disorders, typically. 相似文献
66.
Biomechanical assessment with electromyography of post-stroke ankle plantar flexor spasticity 总被引:1,自引:0,他引:1
Spasticity has been defined as a motor disorder characterized by a velocity-dependent increase in tonic stretch reflex (muscle tone). Muscle tone consists of mechanical-elastic characteristics, reflex muscle contraction and other elements. The aims of this study were to determine whether to assess spasticity quantitatively, and to characterize biomechanical and electromyographic spasticity assessment parameters. These assessment parameters were described by investigating the correlation between clinical measures and the response to passive sinusoidal movement with consecutive velocity increments. Twenty post-stroke hemiplegic patients and twenty normal healthy volunteers were included in the study. Five consecutive sinusoidal passive movements of the ankle were performed at specific velocities (60, 120, 180, and 240 degrees/ sec). We recorded the peak torque, work, and threshold angle using a computerized isokinetic dynamometer, and simultaneously measured the rectified integrated electromyographic activity. We compared these parameters both between groups and between different velocities. The peak torque, threshold angle, work, and rectified integrated electromyographic activity were significantly higher in the post-stroke spastic group at all angular velocities than in the normal control group. The threshold angle and integrated electromyographic activity increased significantly and linearly as angular velocity increased, but the peak torque and work were not increased in the post-stroke spastic group. Peak torque, work, and threshold angle were significantly correlated to the Modified Ashworth scale, but the integrated electromyographic activity was not. The biomechanical and electromyographic approach may be useful to quantitatively assess spasticity. However, it may also be very important to consider the different characteristics of each biomechanical parameter. 相似文献
67.
原发性慢性闭角型青光眼血流动力学改变与视功能损害关系的临床研究 总被引:5,自引:0,他引:5
目的 :探讨眼底血流动力学改变与慢性闭角型青光眼视功能损害的关系。方法 :利用彩色多普勒超声技术 ( CDI)对慢性闭角型青光眼 ( CPCAG)患者的不同病程阶段的眼动脉 ( OA)、视网膜中央动脉 ( CRA)、睫状后短动脉 ( PCAs)的血流参数进行检测 ,对 CPCAG患者视野指数平均缺损值 ( MD)与 OA、CRA、PCAs阻力指数 ( PI)的相关性分别进行研究。结果 :1 CPCAG患者无论是OA还是 CRA、PCAs,其收缩期峰值血流速度 ( PSV)、舒张末期血流速度 ( EDV)、平均血流速度( Vmean)均较正常人减少 ,阻力指数 ( RI)较正常人高 ( P<0 .0 1 )。 2 CPCAG患者的视野 MD值与OA、CRA和 PCA的 RI之间呈显著负相关 ( P<0 .0 1 )。 3CPCAG组随着视野损害的不断进展 ,其眼底血流速度逐渐下降 ,在尚未出现眼底及视野改变的 CPCAG患者中 ,CRA的 EDV降低 ,与正常对照组相比存在显著差异 ( P<0 .0 5)。结论 :1 CPCAG患者存在着视盘和视网膜的血液供应障碍。 2 CPCAG患者的视野损害与眼底血管末梢阻力的增加有关。 3CDI对 CPCAG的早期诊断及病程监测具有重要价值。 相似文献
68.
【目的】调查 5 0岁以上的中老年人群中的原发闭角性青光眼患病率。【方法】 1997年在广东省斗门县以村为单位 ,通过重组随机整群抽样确定检查对象 ,用ETDRS视力表检查裸眼视力、常戴镜视力和针孔视力 ,Schiotz计测定眼压 ,直接电眼底镜作视神经垂直C/D比的估计 ,手电筒侧照法和vanHerrick法测定前房深度 ,并结合急性发作史、前房角镜和视野检查作出诊断。【结果】在 5 34 2名实检对象 (受检率 92 7% )中 ,青光眼是第 5位致盲眼病。原发闭角性青光眼的患病率为1 0 % ,男性和女性中分别为 0 8%和 1 2 % ,在 5 0~ 5 9、6 0~ 6 9和 70~ 98岁年龄组中分别为 0 4%、0 8%和 1 6 % ,浅前房人群中为 5 9% ,经logistic回归校正混杂作用后 ,年龄和前房深度为独立的危险因素 ,以 5 0岁年龄组和深前房者为基准 ,70~ 98岁年龄组和浅前房者的调整比数比分别为 3 3和 11 3。【结论】原发闭角性青光眼是人群中重要的致盲眼病 ,老年和浅前房者是危险人群。 相似文献
69.
目的 对氩激光、倍频Nd:YAG激光、半导体激光小梁成形术的疗效作一前瞻性的评价和比较。方法 随机地将原发性开角型青光眼病人50例84眼分为三个激光组,分别用氩激光、倍频Nd:YAG激光、半导体激光进行小梁成形术,随访三组的有效率。结果 三组各随访期的眼压下降有统计学意义。三组之间的眼压下降数和成功率无差别。结论 三种波长激光都能有效地进行小梁成形术。 相似文献
70.
Elisa Guazzelli Elena Masotti Manfred Kriechbaum Frank Uhlig Giancarlo Galli Elisa Martinelli 《Macromolecular chemistry and physics.》2023,224(3):2200360
Amphiphilic fluorinated copolymers PEGMAx-co-FAy and TEGMAx-co-FAy are prepared by activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP). All polymers present a reversible thermoresponsive lower critical solution temperature-type behavior, and a cloud point temperature (Tc) in the range of 30–60 °C strictly dependent on the length of the oxyethylene side chain, the content of the hydrophobic counits, and the concentration of the solution. Combined small angle X-ray scattering (SAXS) and dynamic light scattering measurements are used to study the self-assembly behavior in water, organic solvents (tetrahydrofuran [THF] and dimethylformamide [DMF]), and a fluorinated solvent (hexafluorobenzene [HFB]). SAXS confirms the formation of compact-globular single-chain self-folded unimer micelles in water below Tc, which generally presents small hydrodynamic diameters (Dh ≤ 8 nm) as a result of the folding of the hydrophobic perfluorohexylethyl acrylate counits. The copolymers are also able to form reverse unimer micelle in HFB. The copolymers are not able to self-assemble in unimer micelles in THF or DMF solutions, in which they adopt conventional random coil conformations. 相似文献