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41.
42.
??Objective    To analyze the principle and evaluate clinical effect of correction on skeletal mandibular deviation by multiloop edgewise arch wire ??MEAW??technique in permanent dentition. Methods    MEAW technique was applied to treat 16 cases of skeletal mandibular deviation with 0.56 mm × 0.71 mm MBT bracket system. Panoramics and cephalometric radiographs were taken and compared before and after treatment. Results    After average treatment time of 20 months??totally 16 cases gained perfect therapeutic effect with molar distal tipping and movement??mean value??tipping 7.63°??movement 3.38 mm????lingual inclination in lower anterior teeth with the change 3.31 mm during treatment??but mandible bone remained asymmetric before and after treatment and there was little change happened on jaws. Conclusion    Skeletal mandibular deviation in permanent dentition can be treated successfully by multiloop edgewise arch wire technique??that is so-called “compensatory treatment”.  相似文献   
43.

Objectives

To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).

Background

Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.

Patients and methods

This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.

Results

The mean age of patients was 3.9?±?2.7?days and their mean weight was 2.8?±?0.19?kg. The mean oxygen saturation was 77.1?±?3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2?days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5?months. Two patients (15.4%) had one and a half ventricle repair at age of 5?months and 6?months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17?±?7?months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from ?0.8?±?0.9 to 0.1?±?0.9) (p?=?0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73?±?0.10 to 0.86?±?0.11 during follow-up (p?<?0.001).

Conclusion

Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation.  相似文献   
44.
目的探讨空心钉张力带微创治疗髌骨骨折的临床效果及安全性。方法将60例髌骨骨折患者随机分为两组,各30例。观察组采用空心钉张力带微创治疗,对照组采用克氏针张力带治疗,对比两组治疗效果及并发症发生情况。结果两组患者手术时间和骨折愈合时间比较差异均无统计学意义(P>0.05),观察组术中出血量少于对照组(P<0.01);观察组优良率为93.3%,高于对照组的70.0%(P<0.05);两组并发症发生率比较,差异无统计学意义(P>0.05)。结论空心钉张力带微创治疗髌骨骨折效果显著,其固定牢固、并发症少、安全有效,值得临床推广应用。  相似文献   
45.
目的:探讨多曲方丝弓在矫治前牙开合畸形中的应用效果。方法:开合患者32例进行矫治,矫治前后进行头影测量分析SNA角、SNB角、ANB角、SN-MP角、U6-PP(mm)、L6-MP(mm)、U1-PP(mm)、L1-MP(mm)、U1-SN(mm)、L1-MP(mm)、ODI角、OB(mm)。结果:矫治结束后患者咬合关系良好,覆合覆盖正常,统计学分析上下磨牙呈轻微压低,上下前牙内收,下前牙直立。结论:多曲方丝弓技术能对开合取得良好效果。  相似文献   
46.
Open reduction and pre-contoured locking plate fixation is a popular treatment option for displaced midshaft clavicle fracture. Lag screw and cerclage are 2 main intraoperative techniques to reduce and fix fragments. However, both lag screw and metallic cerclage have disadvantages. The doubled-suture Nice knot has been reported in many areas of orthopedic surgery for its effectiveness. This study aims to compare the outcomes of comminuted mid-shaft clavicle fractures reduced by Nice knots vs traditional techniques (lag screw or/and metallic cerclage) when bridged with pre-contoured locking plates.We retrospectively reviewed 101 patients (65 females and 36 males) diagnosed with midshaft clavicle fractures with at least one wedge fragment reduced by either Nice knots or traditional methods and bridged with pre-contoured locking plates between December 2016 and April 2019. Operation time, functional outcomes, pain, patient satisfaction, fracture healing, and complications were assessed at a follow-up of 12 to 40 months.The mean age of all the patients was 50.8 years. There were 52 and 49 patients in the Nice knot group and traditional group respectively, and no differences between 2 groups were found in general patient characteristics, fracture type, follow up and injury-to-surgery duration. The Nice knot group had significant less operation time (P < .01) than the traditional group (mean and standard deviation [SD], 78.6 ± 19.0 compared with 94.4 ± 29.9 minutes, respectively). For healing time, functional score, pain, satisfaction and complications, there were no significant differences between groups, despite the Nice knot group had slightly better results.Both Nice knots and traditional methods treated for comminuted Robinson type 2B clavicle fractures were effective and safe. And the Nice knots seemed to be superior with significant less operation time.  相似文献   
47.
目的 研究关节镜辅助下经皮克氏针联合界面螺钉固定治疗Schatzker Ⅲ型胫骨平台骨折的可行性和疗效分析。方法 自2008年5月至2018年1月,中国人民解放军联勤保障部队第910医院骨科采用克氏针联合界面螺钉固定治疗Schatzker Ⅲ型胫骨平台骨折20例。所有病例均采用关节镜辅助,结合骨折微创复位技术进行复位,采用多根克氏针联合界面螺钉固定并结合异体骨植骨。手术后采用HSS评分标准对膝关节功能进行评估。结果 本组20例患者均获随访,术后随访2 ~ 10年,平均(6.7±2.2)年。术后患者切口均Ⅰ期愈合,骨折均达骨性愈合,愈合时间为2.5 ~ 6个月,平均3.1个月,膝关节活动度为0° ~ 130°。末次随访时膝关节功能HSS评分: 优18例,良1例,可1例,优良率95.0%。所有患者均未出现下肢深静脉血栓、切口感染、膝关节僵硬。结论 关节镜辅助下经皮克氏针联合界面螺钉固定治疗Schatzker Ⅲ型骨折具有直视下精确复位、损伤小、愈合快,可一期处理关节腔内其他损伤,有利于功能快速康复,并发症少等优点。  相似文献   
48.
Distal radius fractures are often treated using percutaneous Kirschner wires (K-wires). The sensory nerves in this area, extensor tendons, radial artery and cephalic vein are at risk of injury in this procedure. We undertook a cadaveric investigation to identify probability of damage to these ‘at risk’ structures by measuring their distances in relation to standard K-wire sites. Nine upper limbs from six formalin-preserved cadavers were studied. Four K-wires were placed percutaneously simulating fixation of a distal radius fracture. Careful dissection was done preserving the original position of neurovascular and tendinous structures. Distances to relevant soft-tissue structures from each K-wire were measured using an electronic digital caliper. Distance of superficial nerves from radial styloid and Lister’s tubercle was measured to determine their ‘safe distance’ from these fixed landmarks. None of the superficial nerves were injured by a K-wire. Cephalic vein had been pierced on 4 occasions (4/18) and extensor tendons on 3 occasions (3/18). Wilcoxon signed-rank test was used to compare distance of the superficial nerves from radial styloid and Lister tubercle, and the latter was found to be the safer option. This study highlights the inherent danger in percutaneous K-wire fixation of wrist fractures. Limited size of the area, where K-wires can be positioned, and anatomic variations of neurovascular structures pose obstacles in developing guidelines for reducing risk of injury. We advocate use of mini-open approach and guiding devices to avert complications of inadvertent impalement and damage to these structures.  相似文献   
49.
Introduction  Venoplasty allows the addition or replacement of leads despite subtotal or total subclavian occlusion. Methods  The threshold of the LV pacing lead implanted for biventricular pacing over a period of 18 months increased to greater than 5 V. A pre implant venogram revealed total subclavian occlusion. Venous access was maintained by extraction of the 4 F LV lead over a wire. Subsequently the sheath would not advance despite 6mm balloon inflation to 30 atm with no residual waist. A wire was placed beside the balloon and the balloon was reinflated. Results  The subclavian obstruction was eliminated without damage to the existing leads. Conclusion  The obstruction formed by the fibrous track around an extracted lead may persist despite what appears to be successful balloon dilation. Inflation with a wire beside the balloon increases the effect eliminating the resistant obstruction without damaging the leads. Acknowledgements of Sources of Financial Support:Dr. Worley receives compensation in various forms from Medtronic, Pressure Products, Guidant, and St Jude Medical. Dr. Gohn receives compensation in various forms from Medtronic. No financial support was provided for the creation of this case report  相似文献   
50.
目的 探讨经桡动脉途径行冠状动脉造影及介入术中,上肢血管异常时PTCA导丝的应用价值。方法 我院近3年行桡动脉造影及介入治疗2000例,如果 0.035"J型导丝和亲水超滑导丝在右上肢血管推送过程中遇到阻力,遂撤出导丝,进行上肢局部血管造影,如果疑似桡动脉痉挛的,局部推注维拉帕米100~200ug后再次复查血管造影。结果仍有40例未能成功,其中桡动脉环9例、严重桡动脉狭窄18例、桡动脉发育细小8例、桡动脉痉挛5例,随机分成PTCA导丝组和改股动脉组。PTCA导丝组改用PTCA导丝,最终完成冠状动脉造影检查;改股动脉组直接经股动脉途径行冠状动脉造影术。比较两组手术成功率、操作时间、造影剂用量及局部出血、血肿并发症等情况。结果 两组完成冠状动脉造影成功率比较未见统计学差异(95%比100%,P=0.746),PTCA导丝组操作时间长于改股动脉组[(950.0±125.3)s比(710.0±98.3)s, P=0.032],两组造影剂用量比较未见统计学差异[(50.0±6.3)ml比(47.0±5.9)ml,P=0.18],改股动脉组出血、血肿并发症多于PTCA组(20%比0%,P=0.035 )。结论 经桡动脉途径行冠状动脉造影及介入治疗术中,当上肢血管发生异常,常规导丝不能完成时,换用PTCA导丝,操作轻柔,并发症发生率低,是安全有效的,特别对于不适合经股动脉造影的患者尤为适合。  相似文献   
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