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1.
BackgroundSurgical planning of posterior referencing total knee arthroplasty (TKA) using computed tomography (CT) might lead to over-rotation of the femoral component because CT could not detect cartilage thickness of the posterior femoral condyle. The purpose of this study was to examine the rotational alignment difference of the femoral component between magnetic resonance imaging (MRI) and CT.MethodsFor elderly varus osteoarthritic patients, 66 varus osteoarthritic knee patients that underwent primary TKA were selected. Twenty-seven young patients who underwent primary anterior cruciate ligament reconstruction were selected as control. After the transepicondylar axis (CEA), the surgical epicondylar axis (SEA) and the posterior femoral condylar line (PCL) were drawn on CT and on MRI at the same angles as CT. Then, the practical PCL was drawn on MRI considering the cartilage thickness (the cartilage PCL). The angle between the SEA and the cartilage PCL (the cartilage posterior condylar angle (PCA)) was measured as preoperative planning. To investigate the accuracy of preoperative MRI measurement, the cartilage thickness on posterior femoral condyles was directly measured during TKA.ResultsThe cartilage PCA for varus osteoarthritic patients averaged 1.3 ± 1.3°. The cartilage PCA was 1.8 ± 1.0° significantly smaller than the bone PCA (the PCA measured on CT). Meanwhile, the cartilage PCA was 0.2 ± 0.4° significantly larger than the bone PCA in young people. The preoperative angle measurement on MRI strongly correlated with the direct measurement of cartilage thickness during TKA.ConclusionThere was 1.8° of divergence between MRI and CT in varus osteoarthritic patients due to cartilage degeneration of the medial femoral condyle. Cartilage assessment using MRI was useful for femoral component rotational alignment.  相似文献   
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The techniques used to repair bilateral cleft lip have evolved over time, yet little data exist to compare outcomes using the various techniques. The aim of this study was to retrospectively evaluate and compare the aesthetic outcomes of two types of complete bilateral cleft repair: advancement rotation and a historic cohort repaired with the Manchester technique. A total of 32 consecutive patients who had complete repair of bilateral cleft lips were identified retrospectively from our centre using inpatient records. The first 16 (born between 1994 and 2005) underwent the Manchester repair, the second 16 (born between 2006 and 2010) a Delaire modified advancement rotation technique. Standardised photographs were taken at five years post repair and cropped to isolate the nasolabial component. Appearance outcomes were assessed by 20 members of the cleft and plastic surgery team, who were each asked to rate all 32 images using the Asher-McDade five-point scale. A chi squared test was used to determine whether there was a statistically significant difference in cleft scores between the two approaches. There was a mean (SD) of 2.8 (1.02) in the advancement rotation group and a mean (SD) of 3.1 (1.07) in the Manchester group. There was a statistically significant difference in the distribution of scores in the advancement rotation group compared with the Manchester group, with lower scores (better results) in the advancement rotation group (p=0.003). This study demonstrates that the advancement rotation technique for the repair of bilateral cleft lip defects resulted in a superior nasolabial appearance when directly compared with the Manchester repair at 5 years of age.  相似文献   
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Objective

The aim of the study was to evaluate the loss of truncal rotation over 54 hours after removing Chêneau brace.

Methods

The studied groups consisted of 39 girls aged 10–18 years old, diagnosed with adolescent idiopathic scoliosis (AIS) and treated with Chêneau brace (CAST) and 20 AIS girls aged 10–18 years old, not treated with bracing. Posterior-anterior radiographs were obtained from the clinical assessment of all subjects and were subsequently used to determine Cobb angles. The measurements of the angle of trunk rotation (ATR) were taken with the Scoliometer® and back-contour device during Adams forward bending test by the two evaluators. The changes in ATRs during 54 hours of observation were performed after the brace had been taken off (0, 2, 24, 30, 48 and 54 hours after debracing). This was described using VATR variable, defined as the change in the absolute Scoliometer® readings in the time intervals against the time interval Δt between the measurements. During back-contour assessment the differential factor (kra) has been used for the digital analysis. The changes in kra over 54 hours of observation were expressed as Vkra factor, defined as the difference in the absolute value of the amplitude differential factor (kra) in the time intervals against the time interval Δt between the measurements.

Results

The highest changes were observed in the thoracic as well as in lumbar spine in patients with Cobb angle ≥30°, axial rotation of the apical vertebrae within 5–15°, Risser sign 0–2. The biggest change in the trunk rotation after Chêneau brace had been taken off was noted within the first two hours of observation.

Conclusion

The patients should be advised to take the brace off for a minimum of two hours before the scheduled x-ray, to allow full relaxation of the trunk in order to obtain reliable radiological images of the deformation.

Level of Evidence

Level III Therapeutic study.  相似文献   
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BackgroundBearing dislocation is a serious complication of unicompartmental knee arthroplasty (UKA) with the Oxford knee prosthesis equipped with a mobile bearing. We aimed to clarify the extent of intraoperative movement of the mobile bearing and its relationship with the positioning of prosthesis components in patients undergoing Oxford UKA.MethodsThis retrospective study included 50 patients (50 knees) who underwent Oxford UKA for anteromedial osteoarthritis or osteonecrosis of the knee. Intraoperative bearing movement was assessed at various angles of knee flexion (0°, 30°, 60°, 90°, and 120°). We stratified patients according to the extent of bearing movement posteriorly during intraoperative knee flexion, with or without contacting the lateral wall of the tibial component (with contact, 20 knees; without contact, 30 knees). Postoperative radiographic evaluations were conducted at 1 week postoperatively to assess the positional parameters of the tibial and femoral components (varus/valgus alignment, rotation, mediolateral position). Clinical evaluations were conducted at 1 year postoperatively (maximum flexion angle, Oxford Knee Score).ResultsAbnormal intraoperative movement of the mobile bearing resulting in contact with the lateral wall of the tibial component was associated with a significantly more medial position and external rotation of the tibial component, as well as poorer improvement in knee flexion angle at 1 year postoperatively.ConclusionIn Oxford UKA recipients, the bearing may impinge on the lateral wall of the tibial component during flexion above 60° if the tibial component is placed too medially or exhibits pronounced external rotation, which may limit knee function improvement postoperatively.  相似文献   
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目的:调查酒精使用障碍(AUD)患者的认知功能损害及相关影响因素。方法:选择AUD患者33例为 AUD组,33例健康人为正常对照组。采用心理旋转任务和MATRICS公认认知成套测验(MCCB)进行认知 功能检测,使用逐步线性回归分析探讨 AUD 患者心理旋转功能损害的影响因素。结果:正常对照组与 AUD组在连线测验(TMT)(t=-3.106,P<0.01)、符号编码(BACS)(t=-4.403,P<0.01)、字母编号 Span (LNS)(t=-6.945,P<0.01)、迷宫测验(NAB)(t=-6.740,P<0.01)、简易视觉空间记忆测验-修订版(BVMT-R) (t=-6.218,P<0.01)和认知总分 Comp(t=-4.665,P<0.01)之间差异均有统计学意义。2 组在心理旋转任 务中正确反应时(t=6.904,P<0.01)、错误反应时(t=4.836,P<0.01)、错误个数(t=2.291,P<0.01)及正确率 (t=-4.350,P<0.01)差异均有统计学意义。Spearman相关分析显示心理旋转与MCCB显著相关。逐步线 性回归分析显示BVMT-R是心理旋转功能损害的重要相关因素(t=-2.387,P=0.024)。结论:AUD患者心 理旋转存在缺陷,这种缺陷与视觉空间记忆功能的损害有关。  相似文献   
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《Foot and Ankle Surgery》2022,28(8):1215-1219
BackgroundThe anterior and posterior part of the deltoid ligament have different functions during ankle flexion motion. Partial ligament injuries have been demonstrated in previous clinical reports. However, the efficacy of external rotation stress test in partial injured cases is unavailable till now.MethodsThirty-two fresh cadaveric specimens were included and allocated into two destabilization groups. In the first group, the anterior portion of deltoid ligament (DL) and syndesmotic ligament were sequentially severed, while in the second group, the posterior portion of DL and syndesmotic ligament were sequentially severed. Mortise view radiographs were taken after each destabilization stage when the ankles were placed at plantarflexion and dorsiflexion positions and stressed in standard external rotation force. The medial clear space (MCS) and talar tilt (TT) angle were measured and compared among different destabilization stages.ResultsWhen the ankles were placed at neutral position, the TT significantly increased in all destabilization stages. The MCS significantly increased after the partial deltoid ligament ruptures only with presence of syndesmotic ligament injuries. There was no significant difference of MCS at plantarflexion for all stages of destabilization if the anterior portion of DL is preserved. Similarly, no significant increase of MCS was detected at dorsiflexion if the posterior portion of DL and posterior inferior tibiofibular ligament are intact.ConclusionPartial DL rupture causes ankle rotational instability at different ankle joint positions, especially when combined with syndesmotic injuries. The neutral position is recommended for diagnosis of partial DL ruptures under external rotation stress.  相似文献   
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目的通过分析医科达Precise医用电子直线加速器运动系统原理及相关故障,探讨维修方法,为直线加速器维修提供借鉴意义。方法深入分析医科达Precise加速器运动系统原理,总结仪器特定角度、反方向运动伴抖动现象报i70 Gantry联锁错误、机架不能旋转无联锁报错以及6 MV能量模式报i517 Sctr Limit联锁错误的4例故障,分析可能的故障原因,进行一一排查。结果通过更换电位器、模拟输出板板A08-A、16脚接线、限位开关SW16将出现的4例故障快速有效地解决。结论充分掌握加速器工作原理,根据故障现象,可通过理论分析和实际测量快速排除故障,有效保证设备开机率和良好的运行状态。  相似文献   
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