3D kinematic analysis of the acromioclavicular joint during arm abduction using vertically open MRI.

Many researchers have evaluated the motions of the shoulder girdle, especially scapular and humeral motion. However, few reports exist that describe motions of the acromioclavicular joint. The purpose of the present study was to analyze the 3D kinematics of the acromioclavicular joint during arm abduction using 3D MR images obtained by a vertically open MRI. Fourteen shoulders of seven volunteers were examined in seven static positions from 0 degrees to the maximum abduction in a seated position. 3D surface models of the clavicle and scapula were created, and the movements of the acromioclavicular joint from 0 degrees to each position were calculated using the volume-based registration technique. From these calculations, the translations were evaluated and the rotational motions were analyzed using the concept of the screw axis. In the anteroposterior direction, the clavicle translated most posteriorly (-1.9 +/- 1.3 mm) at 90 degrees of abduction and most anteriorly (1.6 +/- 2.7 mm) at maximum abduction. In the superoinferior direction, the clavicle translated slightly superiorly (0.9 +/- 1.9 mm). When analyzing relative motion of the scapula with respect to the clavicle, the scapula generally rotated about a specific screw axis passing through the insertions of both the acromioclavicular and the coracoclavicular ligaments on the coracoid process. The average rotation was 34.9 +/- 8.4 degrees.     

126例心房颤动合并长R-R间期患者的动态心电图分析

Objective To analyze the relationship between atrial fibrillation complicating long R-R interval, escape beat and escape heart rhythm and pathological atrioventricular block by dynamic electrocardiography (DCG). Methods 126 patients with atrial fibrillation were divided into group A (being related to sleep) and group B (being not related to sleep) according to the factor whether long R-R interval, escape beat and escape heart rhythm relevant to sleep. All were detected by DCG for 24 hours. Results The cases with1.5～2.0 s long R-R interval, more than 2.0s long R-R interval, escape beat and escape heart rhythm were (26.02±6.03), (7.39±1.05 ) and (6.90±1.28)in group A and (203.05±41.01), (35.48±7.52), (28.10±6.25) in group B respectively. The cases of group B were markedly more than those in group A. Conclusion Those atrial fibrillation complicating long R-R interval, escape bbeat and escape heart rhythm were related to sleep could not be deemed as pathological atrioventricular block, while those were not related to sleep could be considered pathological atrioventricular block.     

计算机导航下空心钉内固定治疗股骨颈骨折

目的 探讨计算机导航技术在股骨颈骨折空心钉内固定治疗中的应用，为骨折内固定提供一个新的手术技术。方法 8例股骨颈骨折，术前Garden分型为Ⅰ型3例，Ⅱ型4例，Ⅲ型1例。术中牵引复位后，通过一次C臂机透视正侧位，即可在计算机导航下完成内固定。术后常规透视复查。结果 8例病例全部在导航下完成空心钉的内固定，平均透视时间为15s，远远少于常规内固定所须的时间。结论 计算机导航技术成功应用于空心钉内固定手术，有效减少了手术中X射线的辐射，同时提高了手术的精度，可避免机械引导器的误差，随时反映操作的过程，使手术过程更方便、直观。     

空心钉及空心改锥在骨折治疗中的应用

目的探讨一种新的骨折内固定方法。方法用空心钉及空心改锥对100例不同部位骨折进行内固定治疗。结果所有骨折均一期愈合，内固定可靠，创伤小，金属反应轻微。结论利用空心钉配合空心改锥治疗各种骨折临床效果肯定，值得应用。     

下颈椎椎弓根螺钉置钉技巧探讨

[目的]探讨下颈椎椎弓根螺钉的置钉技巧和手术体会。[方法]2004年7月~2006年4月,在前期尸体标本操作的基础上,C型臂引导下采用下颈椎椎弓根螺钉技术治疗颈椎疾患15例。常规后路,术中显露侧块至其外侧缘,辨清上关节突关节面基底部上缘;选择侧块外缘内5 mm,上关节突关节面基底部下方3 mm处为进钉点,球磨去皮质。2 mm手钻开路并探子确认,保持与上终板平行并40°~45°内倾角。不攻丝置入3.5 mm皮质骨螺钉。[结果]除1枚C4螺钉未能成功外,共计置入C3~7下颈椎椎弓根螺钉86枚,平均螺钉长度(26±1.6)mm,CT下各钉内倾角度平均值37.9°±5.4°。术中2枚(2.9%)在开路时发生钉道活动性出血。术后CT示椎弓根壁损伤6枚(8.8%)。术后无神经血管损伤并发症。[结论]颈椎椎弓根螺钉技术相对安全,置钉成功的关键是手感。     

Effects of angle and laminectomy on triangulated pedicle screws

We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength.     

青年性腰椎弓根崩裂直接修复后TSRH钩钉系统固定12例初步报告

[目的]评价TSRH钩钉系统对青年患者腰椎弓崩裂直接修复后固定的临床疗效。[方法]自2001年7月~2003年10月,对12例男性单纯腰椎弓崩裂患者(16~31周岁)行腰椎弓崩裂自体骨直接修复峡部裂后TSRH椎板钩、椎弓根钉固定术。术后随访,根据术后X线、CT结果评价修复效果,并根据MacNab's标准进行临床评价。[结果]经过6~19个月随访,所有患者腰椎弓崩裂影像学全部融合;临床下腰痛显著缓解,按MacNab's标准,优8例,良3例,一般1例;无手术及内固定相关并发症发生。[结论]直接修复后TSRH钩钉系统固定治疗青年性腰椎弓崩裂能充分保留腰椎运动节段,在减少融合节段的同时能有效恢复腰椎稳定,操作简便、安全,固定可靠,是一种合乎逻辑的治疗青年性腰椎弓崩裂方法。     

拉力螺钉有限内固定结合外固定治疗胫腓骨骨折

2000年10月-2006年8月，我院收治胫腓骨骨折患者115例，其中45例采用有限内固定结合外固定治疗，取得满意疗效，报道如下。     

三种内固定治疗上肢长骨干骨折的临床比较研究

目的观察天鹅记忆接骨器(swan-likememoryconnector,SMC)治疗上肢长骨干骨折的疗效,并与加压接骨板(dynamiccompressiveplate,DCP)和带锁髓内针(lockedintramedullarynail,LIN)进行临床对比研究。方法随机选择1997年8月～2001年8月入院的新鲜上肢长骨干骨折148例,分别采用SMC(49例)与DCP(50例)、LIN(49例)进行内固定治疗,术后常规抗炎治疗1周,定期拍片并随访患肢功能恢复情况。结果SMC组的手术时间明显低于LIN组与DCP组(P<0.05),三组伤口感染率无差异。SMC组骨愈合时间和骨不连发生率显著短于DCP组和LIN组(P<0.05),而术后功能优良率高于DCP组和LIN组。在SMC固定下,骨折愈合直接由解剖型或类解剖型的骨样骨板状直接替代连接,固定段无应力遮挡和骨质疏松。结论SMC是治疗上肢长骨干骨折的有效方法,优于DCP和LIN。SMC的几何构形和力学特性有利于骨折愈合。在本器固定下,可能存在一种新的尚未被认知的骨折愈合方式。