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101.

Background:

Pedicle screw fixation is the most preferred method of stabilizing unstable spinal fractures. Pedicle screw placement may be difficult in presence of fractured posterior elements, deformed spine, gross instability and spinal pathology. Challenging spine-fracture fixation is defined as the presence of one or more of the following: 1) obscured topographical landmarks as in ankylosing spondylitis, 2) fractures in occipitocervical or cervicothoracic regions and 3) preexisting altered spinal alignment. We report a series of pedicle screw insertion with guidance of navigation in difficult fixation problems..

Materials and Methods:

Fourteen patients [hangman''s fracture (n=3), odontoid fracture (n=4), C1C2 fracture (n=1) and spinal fracture with coexistent ankylosing spondylitis (n=6)] underwent posterior stabilization. Intraoperatively after surgical exposure, images were acquired by Iso-C 3D C-arm and transferred to navigation system. Instrumentation was performed with navigational assistance. Postoperatively, placements of pedicle screws were evaluated with radiographs and CT scan.

Results:

Sixty-seven pedicle screws (cervical, n=33; thoracic, n=6; lumbar, n=26; sacral n=2) and 15 lateral mass screws were inserted with navigation guidance. The average time of image data acquisition by Iso-C 3D C-arm and its transfer to workstation was 4 minutes (range, 2-6 minutes). Postoperative CT scan revealed ideal placement of screws in 63 pedicles (94%), grade 1 cortical breaches (<2 mm) in 3 pedicles (4.5%) and grade 2 cortical breach (2-4 mm) in one pedicle (1.5%). There were no neurovascular complications. Deep infection was encountered in one case, which settled with debridement.

Conclusions:

Intraoperative Iso-C 3D C-arm based navigation is a useful adjunct while stabilizing challenging spinal trauma, rendering feasibility, accuracy and safety of pedicle screw placement even in difficult situations.  相似文献   
102.
Work‐based support has effects on family outcomes (Thompson, Kirk, & Brown, Stress and Health, 2005, 21, 199–207), suggesting that the effects of work‐based support are transmitted to the family environment through some mediating mechanism. This study examines two potential mediating mechanisms, emotional exhaustion and work interference with family (WIF). It was expected that women would report higher levels of work support, and work support would have a stronger relationship with outcomes for women. Gender as a moderator of the relationships between work support, and emotional exhaustion, WIF, and family environment (family cohesion, family conflict) was tested via regression analyses. Eighty‐one males (43.3 per cent) and 106 females (56.7 per cent), and their spouse/partners participated in the study. Women reported higher levels of coworker support than men, and support from supervisors predicted WIF only for women. Gender did not moderate the work support—family environment relationship. WIF, but not emotional exhaustion, mediated the relationship between supervisor and coworker support, and employee reports of family cohesion. Spouse/partner reports of family environment were not predicted by the study variables. Thus, work support reduces employee negative perceptions of the family environment through reduced work–family stress, and the impact is similar for men and women. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
103.
目的:探讨采用单纯后路广泛松解技术联合侧凸全节段椎弓根螺钉系统治疗青少年特发性胸腰椎和腰椎脊柱侧凸的疗效。方法:我院于2002年4月至2005年7月连续收治了114例(女86例,男28例)青少年特发性胸腰椎和腰椎脊柱侧凸患者,其中Lenke5型72例,Lenke6型32例,Lenke3C型10例。全部采用后路广泛松解技术联合椎弓根螺钉系统治疗。手术前后在X线正侧位片上测量冠状位Cobb角,矢状面胸椎后凸角和腰椎前凸角,最下端融合椎冠状面成角,骶骨中垂线与融合下端椎、顶椎及C7中垂线平均距离,并观察各种并发症情况。结果:共置入1460枚椎弓根螺钉,平均融合9.6个椎体(5~14个)。冠状面平均矫正率为78.6%(61°减少到13°),矢状面腰椎前凸角从36°(23°~67°)增加到42°(34°~55°)。最下端融合椎冠状面成角矫正率达79%,骶骨中垂线与融合下端椎距离从2.3cm减少到0.5cm,与顶椎距离从5.0cm缩短到1.6cm;C7中垂线与骶骨中垂线距离由2.7cm减少到0.8cm。术后平均随访时间为30个月(12~50个月),未发现假关节形成、深部感染,且无明显矫形丢失。结论:后路广泛松解联合全节段椎弓根螺钉系统治疗青少年特发性胸腰椎/腰椎侧凸效果满意。  相似文献   
104.
目的评价两孔动力髋螺钉(DHS)微创内固定治疗股骨颈骨折的疗效。方法回顾分析48例股骨颈骨折在C型臂X线机透视下闭合复位,采用微创手术入路经皮两孔DHS微创内固定治疗,评价其疗效。结果切口长度平均为3.0cm,出血量平均为41.5ml,手术时间平均为25min。46例骨折愈合,2例骨折不愈合,愈合率为95.8%。3例出现股骨头缺血坏死(其中骨折不愈合2例,骨折愈合后发生1例)。结论应用经皮微创两孔DHS内固定术治疗股骨颈骨折,手术简便快速,创伤少,固定牢固,是治疗股骨颈骨折理想的微创治疗技术。  相似文献   
105.
目的 探讨关节镜下可吸收螺钉固定腘绳肌腱单束重建膝后交叉韧带(posterior cruciate ligament,PCL)的效果.方法 2004年4月~2005年4月,我院25例(25膝)经关节镜检查证实为PCL断裂,在关节镜下行自体腘绳肌腱单束PCL 重建术,生物可吸收挤压螺钉解剖位固定重建韧带. 结果 手术时间平均90min(80~100min).25例膝术毕PCL重建后后抽屉试验均为阴性.术后住院时间7~14 d,平均10.4 d.25例术后随访12~24个月,平均18个月,23例膝后抽屉试验阴性,2例后抽屉试验1级.术后12个月Lysholm膝关节功能评分由术前(44.8±8.1)分提高至(77.8±6.4)分(t=-15.999,P=0.000).按国际膝关节文件编制委员会膝关节标准评价膝关节功能分级,术前异常(C级)10例、显著异常(D级)15例,随访时正常(A级)8例、接近正常(B级)15例、异常(C级)2例(Z=-4.394,P=0.000). 结论 关节镜下可吸收螺钉固定自体腘绳肌腱单束重建膝PCL创伤小,固定可靠,手术操作简单,术后膝关节功能恢复效果好.  相似文献   
106.
目的初步观察用小分子干扰RNA(siRNA)沉默树突状细胞(DCs)恒定链(Ii)后,DCs疫苗的体外抗肿瘤效果。方法从小鼠骨髓分离骨髓前体细胞,细胞经100 ng/ml GM-CSF和100 ng/ml IL-4诱导培养6 d后,转染针对DCs Ii链特异的Ii-siRNA,转染后加用50 ng/ml TNF-α继续诱导细胞成熟48 h,然后分别用Western blot检测沉默效果及CCK-8试剂盒检测DCs刺激同种异体淋巴细胞增殖的能力;此外,DCs共转染Ii-siRNA和小鼠胃癌前体细胞MFC的总RNA后,与同种异体淋巴细胞共培养,通过ELISA检测培养上清IFN-γ/和IL-4的水平,并收集致敏淋巴细胞进行体外杀伤实验。结果Ii-siRNA明显抑制DCs Ii的表达。沉默Ii链能够增强DCs的淋巴细胞增殖能力,并促使淋巴细胞向Th1的方向漂移[IFN-γ:(5107±351)pg/ml,IL-4:(65±13)pg/ml,P<0.05]。淋巴细胞经共转染Ii-siRNA和MFC RNA的DCs激活后,明显而特异地杀伤靶肿瘤细胞(杀伤百分率: 66.94%±2.75%,P<0.05)。结论通过siRNA沉默DCs的Ii链可能是一种行之有效的增强抗肿瘤免疫的方法。  相似文献   
107.
目的 探讨一期经前路病灶清除后路植骨内固定治疗L5S1椎体结核的临床疗效.方法 对40例L5S1椎体结核患者,采用一期经前路病灶清除椎体间植骨加后路椎弓根螺钉内固定植骨融合治疗.结果 所有患者随访6~24个月,35例植骨融合良好,5例融合欠佳;有1例出现尿路感染.结论 一期经前路病灶清除椎体间植骨加后路椎弓根螺钉内固定椎板植骨治疗L5S1椎体结核能在彻底清除病灶的前提下保证脊柱的稳定性,提高植骨块的融合率和缩短患者卧床时间.  相似文献   
108.
目的对单枚融合器联合单侧钉棒系统固定的生物力学性能进行评价。方法5具新鲜小牛腰椎标本,建立以下力学模型:A组:双侧开窗+双枚融合器置入+双侧椎弓根钉棒固定;B组:单侧小关节切除+单枚融合器斜向置入+同侧椎弓根钉棒固定;C组:单侧开窗+单枚融合器置入+同侧椎弓根钉棒固定;D组:单侧开窗+单枚融合器置入+对侧椎弓根钉棒固定。在生物力学平台上测试各试验组在不同工况下的ROM值。结果A组的固定最稳固,各工况下ROM值最低。B组的前后抗弯ROM值与A组差异无显著性,其左右侧弯和旋转方向的稳定性较A组有所降低。与B组比较,D组的前后弯曲性能与B组差异无显著性,其左右侧弯方向的ROM低与B组。两组的抗旋转ROM值差异无显著性。C组的左右抗弯及抗旋转性能均差于B、D组。结论单枚椎间融合器联合对侧椎弓根钉棒固定是一种力学性能较为优良组合,可以替代单侧斜向融合器并同侧椎弓根钉棒技术用于下腰椎微创手术。  相似文献   
109.
Hasenboehler E  Rikli D  Babst R 《Injury》2007,38(3):365-370
With the introduction of Locking Compression Plates (LCP), Minimally Invasive Plate Osteosynthesis (MIPO) has become widely used. The plates act as internal fixators in a bridging manner, thus resulting in secondary bone healing. We retrospectively evaluated the healing pattern and the clinical evolution of diaphyseal and distal tibial shaft fractures over two and a half years in 32 patients (6 females, 26 males). Fractures were classified according to AO classification and included all 42A-C, 43A-B and 43C1-2 types. For open fractures, Gustillo Anderson classification was used. Plates consisted of the 4.5mm LCP and 3.5mm LCP-Pilon form plate. Clinical and radiological assessment was performed at 6 weeks, and at 3, 6, 9, and 12 months. Two patients were lost to follow-up. Fracture healing was defined as callus bridging of one cortex, seen on both lateral and posterior-anterior X-ray, and full, painless weight bearing. Ten patients at 3 months, 23 at 6 months, and 27 at 9 months met the criteria for a healed fracture. Plate bending was observed in one patient and called for re-operation at 5 months. Two patients required re-operation at 13 months secondary to pseudoarthrosis. Though MIPO seems more advantageous for soft tissue and bone biology, prolonged healing was observed in simple fracture patterns when a bridging plate technique was used.  相似文献   
110.
PURPOSE: Temporary intercarpal screw fixation has been suggested as an alternative to temporary K-wire fixation in the treatment of perilunate wrist dislocations. We compared the 2 treatment methods in 2 retrospective cohorts with a null hypothesis that there would be no difference in final wrist motion. METHODS: Eighteen patients with surgically treated perilunate wrist dislocations (9 treated with intercarpal screws, 9 with intercarpal K-wires) were evaluated an average of 44 months after injury. The intercarpal screws were removed an average of 5 months and the K-wires an average of 3 months after the initial procedure. Complications included 3 pin track infections (1 with wrist sepsis), 2 scaphoid nonunions (screw fixation), and 2 patients with loss of reduction (K-wire fixation) treated with repeat surgery. RESULTS: Four patients (2 in each cohort) had wrist arthrodesis with poor results. Among the 14 remaining patients the final flexion arc was 97 degrees for patients treated with screw fixation compared with 73 degrees for patients treated with K-wires. The mean grip strength was 74% (screw fixation) and 67% (K-wire) that of the uninjured arm. According to the Mayo Modified Wrist Score, the functional result was excellent in 1 patient (screw), good in 2 patients (1 each group), fair in 6 patients (3 in each group), and poor in 9 patients (4 screws, 5 K-wire). Seven patients (2 screws, 5 K-wires) had grade 2 or 3 midcarpal arthritis according to the criteria of Knirk and Jupiter, but none had more than mild radiocarpal arthritis. CONCLUSIONS: The results of treatment with temporary screws are comparable to the results of treatment with temporary K-wires. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.  相似文献   
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