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1.
目的分析细棒、PEEK棒固定对寰枢关节稳定性的影响。方法采用6具新鲜成人枕骨(occipital bone,Oc)~颈椎C4节段进行测试,模拟以下手术及固定状态:①完整状态;②损伤状态:枢椎齿状突II型骨折;③坚强固定:寰枢椎均采用普通椎弓根螺钉固定,直径3.5 mm钛棒连接;④PEEK棒:直径3.5 mm的PEEK棒连接;⑤细棒:直径2.0 mm钛棒连接。采用重复测量实验设计,在完整、损伤和不同的固定状态下,通过脊柱试验机对标本分别施加1.5 N·m的前屈/后伸、左/右侧弯和左/右轴向旋转的纯力偶矩。采用Optotrak三维运动测量系统连续采集标本运动,分析寰枢椎之间角度运动范围和中性区。结果采用直径3.5 mm的钛棒,2.0 mm的细棒以及3.5 mm的PEEK棒固定后,在前屈、后伸、侧弯和旋转方向上均显著减小了固定节段的运动范围(P<0.05)。直径3.5 mm和2.0 mm的棒固定后的运动范围,在各个方向上无显著性差异。PEEK棒固定的运动范围仅在侧弯方向上大于坚强固定(P=0.005),其他方向无显著性差异。3种固定方式在屈伸、侧弯和旋转方向上均显著减小了固定节段的中性区(P<0.05)。各种固定方式之间相比较,无显著性差异(P>0.05)。结论在寰枢关节采用直径2.0 mm的细棒固定,与坚强固定的稳定性相当。采用直径3.5 mm的PEEK棒固定,在前屈、后伸、旋转方向上与坚强固定的稳定性相当,在侧弯方向上弱于坚强固定。  相似文献   
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正枕骨、寰椎和枢椎共同构成了枕颈部活动的结构功能单位,即枕颈交界区~([1-2])。炎症、创伤、肿瘤及畸形等因素会导致枕颈交界区失稳,从而引起颈脊髓或神经根的损伤、麻痹及难以忍受的疼痛,甚至危及生命~([3-4])。后路内固定融合技术是治疗枕颈部失稳的重要手段,目前常用术式为枕骨螺钉技术,该技术较钢丝固定技术有更好的生物力学稳定  相似文献   
4.

Background:

The Composite International Diagnostic Interview-3.0 (CIDI-3.0) is a fully structured lay-administered diagnostic interview for the assessment of mental disorders according to ICD-10 and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. The aim of the study was to investigate the concurrent validity of the Chinese CIDI in diagnosing mental disorders in psychiatric settings.

Methods:

We recruited 208 participants, of whom 148 were patients from two psychiatric hospitals and 60 healthy people from communities. These participants were administered with CIDI by six trained lay interviewers and the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I, gold standard) by two psychiatrists. Agreement between CIDI and SCID-I was assessed with sensitivity, specificity, positive predictive value and negative predictive value. Individual-level CIDI-SCID diagnostic concordance was evaluated using the area under the receiver operator characteristic curve and Cohen''s K.

Results:

Substantial to excellent CIDI to SCID concordance was found for any substance use disorder (area under the receiver operator characteristic curve [AUC] = 0.926), any anxiety disorder (AUC = 0.807) and any mood disorder (AUC = 0.806). The concordance between the CIDI and the SCID for psychotic and eating disorders is moderate. However, for individual mental disorders, the CIDI-SCID concordance for bipolar disorders (AUC = 0.55) and anorexia nervosa (AUC = 0.50) was insufficient.

Conclusions:

Overall, the Chinese version of CIDI-3.0 has acceptable validity in diagnosing the substance use disorder, anxiety disorder and mood disorder among Chinese adult population. However, we should be cautious when using it for bipolar disorders and anorexia nervosa.  相似文献   
5.
IntroductionMorphometric evaluation of the pedicle and isthmus of second cervical vertebra (C2) (Axis) is extremely vital before contemplating any surgical stabilization involving the Craniovertebral region, in view of its proximity to the vertebral artery and the cervical nerve root. The dimensions of pedicles and isthmuses in C2 vary between individuals and there is paucity of data in the Indian population. This study strives to measure the average pedicle and isthmus dimensions in a sample of population, which would enable selection of screws with safest diameters to be used in C2; thereby avoiding injury to adjacent neurovascular structures.Materials and methodsOne Hundred patients in the age group between 18 and 70 years who underwent CT scan of head and neck region were included in the study. The aim of this study was to assess the anatomic suitability of transarticular and pedicle screw placement in Axis vertebrae of Indian population and determine the maximum safe diameter for screw placement. The following parameters were measured in millimeters: Pedicle width, Pedicle angle, Internal height and Isthmic height.ResultsThe Mean maximum diameter of potential pedicle screw was 4.99 ± 1.1 mm for the right side with the left side being slightly wider at 5.20 ± 1.16 mm. Twenty eight (28%; 56 out of 200 pedicles) had a measurement < 4.5 mm. The internal height in sagittal images representing the pedicle height was found to be 4.79 ± 0.96 mm on the right side and 4.75 ± 1.04 mm on the left side. Sixty five (65) out of 200 pedicles (32.5%) had measurements < 4.5 mm in sagittal plane. The Mean maximum diameter of potential Transarticular screw (outer diameter of isthmus) was 5.05 ± 0.78 mm for the right side and 5.18 ± 0.84 mm on the left side.DiscussionIsthmic height < 4.5 mm could potentially violate the vertebral foramen when a 3.5 mm screw is used. In our study 22.5% isthmuses were narrow (<4.5 mm). The mean maximum safe diameter for a potential transarticular screw in the present study was 5.11 mm. Though our patients had smaller isthmus dimensions compared with literature, 77.5% of C2 could take a 4 mm transarticular screw quite comfortably considering the 0.5 mm margin on either side. In the present study, 28% of pedicles were found to be inappropriately sized (<4.5 mm) to accommodate the standard 3.5 mm screw. The mean maximum diameter of a potential pedicle screw in our study was 5.09 mm; and in 72% of patients a 4 mm screw could be placed with confidence. Though our patients on an average can accommodate a 4 mm screw comfortably, we suggest a protocol of obtaining CT measurements of C2 prior to operative intervention for identifying those individuals at risk of neurovascular injury; 22.5% for transarticular screw and 28% for pedicle screw.  相似文献   
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7.
目的:通过CT测量探讨枢椎峡部螺钉固定技术的安全性和可行性。方法:收集2016年1月至2019年12月进行全颈椎CT检查的137例结构完整的上颈椎CT数据,其中男71例,女66例;年龄22~65(41.8±17.4)岁。通过Mimics19.0软件测量峡部螺钉技术相关的解剖学数据,包括峡部宽度、峡部垂直长度、峡部垂直高度、峡部螺钉通道长度、峡部螺钉通道头倾角度。并分析各项指标之间的相关性。结果:枢椎峡部宽度(9.05±1.63) mm,垂直长度(11.21±1.43) mm,垂直高度(17.53±2.93) mm。螺钉通道长度为(19.07±3.20) mm。峡部螺钉通道长度>14 mm的占94.53%,14~16 mm的占82.12%,16~18 mm的占63.14%,18~20 mm的占39.78%。螺钉通道的头倾角度为30°~68°,平均(46.06±8.06)°。螺钉通道长度和头倾角度呈高度正相关(r=0.965,P=0.000)。峡部垂直长度和螺钉通道长度,峡部垂直长度和螺钉的头倾角度之间都呈轻度正相关(r=0.240,P=0.000;r=0.163,P=0.007)。峡部宽度和螺钉通道长度,峡部宽度和螺钉通道的头倾角度之间都呈中度负相关(r=-0.333,P=0.000;r=-0.380,P=0.000)。结论:进行枢椎后路峡部螺钉固定安全、可靠,比枢椎后路椎弓根螺钉固定具有更大的适用范围,可以作为椎弓根螺钉的替代选择。  相似文献   
8.
目的 测量寰枢椎后方结构相关数据,为设计寰枢椎后路内固定系统提供解剖学依据。 方法 测量30例寰椎和枢椎骨标本、50例男性和50例女性CT寰枢椎后方结构相关数据,分别比较骨标本、CT图像测量指标的侧别及性别统计学差异,比较骨标本数据和CT数据统计学差异。 结果 骨标本测得后中线处高(10.75±1.38)mm、厚(8.55±1.77)mm,内、外侧后中线到两侧椎动脉沟内侧缘距离分别为(13.45±0.73)mm、(20.28±2.20)mm,内、外侧缘后弓夹角分别为(141.00±3.43)°、(134.67±2.87)°。CT测量后中线处高(10.45±1.61)mm、厚(8.12±1.57)mm,内、外侧后中线到两侧椎动脉沟内侧缘距离分别为(13.60±1.26)mm、(20.48±2.05)mm,内、外侧缘后弓夹角分别为(141.23±9.64)°、(135.47±9.02)°,后弓外侧缘半径(26.77±2.14)mm,枢椎板斜率(58.34±7.60)°,寰椎后弓下缘至枢椎棘突上缘高(19.07±2.73)mm,寰枢椎后间隙高(6.83±2.01)mm。CT数据大部分性别差异有统计学意义(P<0.05)。骨标本和CT数据左右侧差异均无统计学意义(P>0.05)。骨标本与CT数据差异无统计学意义(P>0.05)。 结论 寰枢椎后方骨性结构解剖特征较为固定;CT能较好地反映该特征;本研究可为寰枢椎后路内固定系统设计提供解剖学依据。  相似文献   
9.
10.

Objectives

To assess the accuracy of a novel, non-invasive method for determining the axis of rotation of articulated dental study casts.

Method

A 3D structured light scanner was constructed using a projector and two CMOS cameras. Dental stone casts were arbitrarily mounted on an average value articulator. With the teeth together, sets of 10 scans were taken from three different viewpoints. Each scan captured approximately six upper teeth and six lower teeth. The teeth were then propped open, creating 10 mm of incisal separation, and the three sets of 10 scans were repeated. From each pair of scans an axis of rotation was calculated using custom software. A total of 900 axes were created this way. The locations of these axes were plotted in sagittal planes located 57.5 mm left and right of the midline to represent the position of the temporo-mandibular joints (TMJs). The accuracy of axis location was then assessed.

Results

The average radius of error of the individual axes, compared to the real axis, was 2.65 ± 1.01 mm. 61.3% of the axes lay within 3 mm of the true axis, and 99.2% of the axes lay within 5 mm of the true axis.

Conclusions

The accuracy of this method is clinically acceptable. Further studies are required to confirm the accuracy of the virtual inter-occlusal records at the level of the dentition. Clinical studies are then indicated to determine whether the transverse horizontal axis on a patient can similarly be determined.  相似文献   
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