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41.
We observed the changes in the angular measurements commonly used in the evaluation of the first metatarsal and first metatarsophalangeal joint in cadaveric specimens before and after frontal plane rotation of the first metatarsal. Measurements of the first and second intermetatarsal angle (IMA), hallux abductus angle, proximal articular set angle, and tibial sesamoid position (TSP) were taken after varying degrees of varus and valgus rotation of the first metatarsal. Standard dorsoplantar radiographs were taken at 0°, 10°, 20°, and 30° of valgus rotation of the first metatarsal and repeated at 10°, 20°, and 30° varus rotation of the first metatarsal. The data were analyzed using a mixed linear model to compare the change in each angle measurement over the range of valgus and varus rotation. The change in the TSP was significant in both valgus and varus rotations (p = .0004 and p = .028, respectively), an increase in valgus rotation causing an increase in the TSP and an increase in varus rotation causing a decrease in TSP. The change in the IMA was significant compared with valgus rotation (p = .028), showing that as the valgus rotation increased, the IMA also increased. However, compared with the varus rotation, the correlation was not significant (p = .18). The proximal articular set angle and hallux abductus angle measurements, compared with metatarsal rotation, showed positive trends but were not statistically significant. From our results and a review of the published data, we have hypothesized that frontal plane rotation of the first metatarsal is an integral component of hallux abducto valgus pathologic features, specifically in relation to the TSP and IMA.  相似文献   
42.
目的 对比斜仰截石位与俯卧位在治疗合并通气功能障碍的上尿路结石患者中的应用安全性及疗效.方法 回顾性分析201 1年10月至2013年10月,采用斜仰卧截石位与俯卧位治疗的合并通气功能障碍的上尿路结石患者60例的资料.结果 60例手术均顺利.手术时间斜仰截石位组(50.4±26.4)min,俯卧位组(50.2±31.4)min;术后复查KUB,一期结石清除率斜仰截石位组83.3%,俯卧位组80.0%;两组术中均无严重并发症发生.斜仰截石位组生命体征变化出现时间(40±5.8)min,俯卧位组生命体征变化出现时间为(30±3.8)min,术中出现血压变化、心率变化、心律变化、呼吸变化,斜仰截石位组均小于俯卧位组.结论 斜仰截石位经皮肾镜取石术具有创伤小安全性高等优点,尤其适用于合并通气功能障碍的上尿路结石患者.  相似文献   
43.
44.
《The Journal of arthroplasty》2019,34(8):1711-1717
BackgroundThe declining popularity of cemented acetabular components is incongruous, given the published results of prostheses implanted using contemporary techniques. The outcome of arthroplasty has previously been demonstrated to correlate with surgeon experience and volume of practice. We aim to explore if surgeon volume alters outcomes of cemented acetabular components based on survivorship data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).MethodsAn observational study was undertaken using a cohort of 22,956 patients with a primary diagnosis of osteoarthritis in the period 2003-2016 in whom cemented acetabular components were implanted. The cohort was stratified by age (greater than or less than 65 years) and annualized surgical volume of ≤10, >10-≤25, and >25 cases.ResultsStratified by age and volume, there was a protective benefit against revision conveyed at volume thresholds of 10 cases per annum and 25 cases per annum for patients ≥65 years of age and <65 years of age, respectively.ConclusionCemented total hip arthroplasty has excellent survivorship out to 15 years based on AOANJRR data. This survivorship is further improved if surgeons perform a higher volume of cases, with >25 cases conferring the greatest benefit. The AOANJRR data set is used to define best practice; surgeons who choose to utilize cemented acetabular fixation should be encouraged to perform this technique in adequate volumes to minimize revision risk and ensure the preservation of this important surgical skill set.  相似文献   
45.
We assessed the impact of raising the upper section of the bed, and patient positioning, on ultrasound assessment of gastric fluid contents. We performed ultrasound examinations in 25 subjects lying on their back, left and right sides at bed angles of 0°, 30°, 45° and 90°; this was carried out while the subjects were fasted, and repeated 10 min after drinking ≥ 50 ml water. After drinking, gastric contents were detected more frequently in the 45° semirecumbent position compared with the supine and 30° positions. The diagnostic performance of the Perlas qualitative grading scale to detect gastric fluid volume > 1.5 ml.kg−1 was improved at 45°, compared with 0° and 30° angles. The use of a composite ultrasound grading scale at a 45° angle was associated with the best performance, with a sensitivity and specificity of 82%. Antral cross-sectional area was significantly increased when measured in the right lateral position, but there was no effect of raising the bed. In conclusion, raising the upper section of the bed significantly affected qualitative assessment of gastric fluid contents. Further studies are required to determine the most appropriate composite ultrasound grading scale and bed angle for fast and reliable qualitative ultrasound detection of fluid volumes > 1.5 ml.kg−1.  相似文献   
46.
目的:比较在三维影像选取双侧耳点和双侧眶下点构建的不同水平面之间差异,分析不同水平面对双侧耳点和双侧眶下点位置的影响,为颅面部三维头影测量水平参考平面的确定提供依据。方法:选取32名正畸治疗前面部基本对称患者(颏下点离正中矢状面≤2 mm), 获取DICOM格式的大视野锥形束CT数据并导入到Dolphin软件,将鼻根点、蝶鞍点和枢椎齿突最高点构建正中矢状面,测量双侧耳点和双侧眶下点中随机三点构建的4种水平参考平面。分别定义为,平面1:水平面由右侧耳点和双侧眶下点构成;平面2:水平面由左侧耳点和双侧眶下点构成;平面3:水平面由双侧耳点与右侧眶下点构成;平面4:水平面由双侧耳点与左侧眶点构成。记录4个平面在三维空间当中的俯仰角、侧偏角和横滚角。间隔两周,一位研究者进行两次测量。计算组间相关系数(interclass correlation coefficient,ICC)比较两次测量结果的一致性,检验测量者自身的可靠性,进行单因素重复测量方差分析检验组内4个平面之间的差异,按年龄分为13~17岁组和≥18岁组。以枢椎齿突最高点为原点计算双侧耳点和双侧眶下点位置,应用圆周长公式分析头部转动对双侧耳点和双侧眶下点的影响。结果:单因素重复测量方差分析结果显示,不同三点构建的4种平面之间俯仰角、侧偏角和横滚角差异均无统计学意义(P=0.196、0.314、0.341)。头位转动对双侧耳点和双侧眶下点的影响分析结果为:1°俯仰角变化产生耳点约0.5 mm、眶下点约1.6 mm的变化;1°侧偏角变化产生耳点约1.1 mm、眶下点约1.5 mm的变化;1°横滚角变化产生耳点约1.2 mm、眶下点约0.7 mm的变化。结论:对于面部基本对称个体,应用三维头颅影像对双侧耳点和双侧眶下点中随机选取三个点构建的4种水平面之间差异无统计学意义;以双侧眶下点和右侧耳点构建的水平面可能最适合临床使用;头部不同方向的转动使双侧耳点和双侧眶下点产生不同位置的变化。  相似文献   
47.
目的 探讨人字形分腿位与截石位对妇科腔镜手术患者的影响.方法 将200例实施妇科腔镜手术患者随机分为对照组和观察组各100例.对照组采用常规截石体位;观察组采用人字形分腿位,即采用可分腿板式手术床,无需安装托腿架,双下肢平放于腿板上,腿板水平分开角度90°~1 00°.结果 观察组体位安置耗时(237.00±58.00)s,对照组(151.00士17.00)s,两组比较,差异有统计学意义(P<0.01);观察组体温、血压、心率变化幅度小于时照组(均P<0.01),麻醉苏醒期平稳性、术后舒适度改变等指标优于对照组(均P<0.01).结论 与截石位相比,人字形分腿住手术野暴露充分,摆放简便,可有效预防并发症的发生,提高手术安全性.  相似文献   
48.
Lymphoblastic lymphoma, an aggressive mediastinal mass, is recognized as serious threat to the patient in developing cardiac tamponade or airway obstruction. Surgical procedure is often required to relieve clinical emergency and to establish prompt pathological diagnosis. However, in such a patient, acute respiratory occlusion in the spine position can be a life-threatening complication during general anesthesia. We describe a 17-year-old man whose cardiac tamponade was treated by pericardial-pleural window through a left anterior thoracotomy in the lateral position. The patient recovered from hemodynamic compromise without showing respiratory occlusion during general anesthesia and remained in the lateral position until extubation. Pathological diagnosis was precursor T-lymphoblastic lymphoma. There were no complications attributable to the operative procedure. Further chemotherapy reduced the mediastinal mass in size after two weeks when the patient developed sepsis and died. Lateral position prevents respiratory occlusion during surgical procedure under general anesthesia in the patient of huge anterior mediastinal tumor with airway obstruction.  相似文献   
49.
Compliant positioning of total hip components for optimal range of motion.   总被引:22,自引:0,他引:22  
Impingement between femoral neck and endoprosthetic cup is one of the causes for dislocation in total hip arthroplasty (THA). Choosing a correct combined orientation of both components, the acetabular cup and femoral stem, in manual or computer-assisted implantation will yield a maximized, stable range of motion (ROM) and will reduce the risk for dislocation. A mathematical model of a THA was developed to determine the optimal combination of cup inclination, cup anteversion, and stem antetorsion for maximizing ROM and minimizing the risk for cup-neck impingement. Single and combined hip joint motions were tested. A radiographic definition was used for component orientation. Additional parameters, such as stem-neck (CCD) angle, head-neck ratio, and the design of the acetabular opening, were also considered. The model showed that a maximized and safe ROM requires compliant, well-defined combinations of cup inclination, cup anteversion, and stem antetorsion depending on the intended ROM. Radiographic cup anteversion and stem antetorsion were linearly correlated. Additional internal rotation reduced flexion, and additional external rotation reduced extension, abduction and adduction. The articulating hemispheric surface of acetabular cups should be oriented between 40 degrees and 45 degrees of radiographic inclination, between 20 degrees and 28 degrees of radiographic cup anteversion, and should be combined with stem antetorsion so that the sum of cup anteversion plus 0.7 times the stem antetorsion equals 37 degrees. Final component orientation must also consider cup containment, implant impingement with bone and soft tissue, and preoperative skeletal contractures or deformities to achieve the optimal compromise for each patient.  相似文献   
50.
目的:评价320排肾脏CTA(CT血管造影)"在腰肋悬空"仰卧位经皮肾镜碎石术中的应用价值及腰肋悬空仰卧位的影像解剖学特点。方法:2010年9月~2011年7月对23例肾结石患者术前行320排肾脏CTA及三维重建,明确肾脏分支血管分布情况及肾脏与周围脏器毗邻关系,进而设计最佳穿刺路径建立经皮肾穿刺通道。患者平均年龄(49.5±11.5)岁;最大径2~6cm,平均为(2.97±1.29)cm。均采用椎管麻醉;手术体位采用腰肋悬空仰卧位。在B超引导下穿刺肾盂或目标肾盏成功后,依次扩张通道至F16或F20,用钬激光或三代超声将结石完全击碎。术后复查320CTA验证穿刺路径及了解结石残留情况。结果:肾脏320排CTA可清晰显示肾内分支血管分布情况。本组23例患者全部穿刺成功,建立通道满意,一期清石率82.6%(19/23)。所有患者均未输血,无胸膜及内脏器官损伤。术后320排CTA检查显示肾造瘘管位于肾脏无血管区。结论:320排CTA可以明确结石、肾盂肾盏、肾分支血管分布及三者关系,真实反映肾脏与周围器官毗邻关系,以利于设计最佳通道,从而降低大出血及损伤邻近脏器风险。腰肋悬空仰卧位时经腋后线于水平方向进针,可通过肾脏无血管区建立通道。  相似文献   
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