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101.
目的通过比较四种不同长度的锁定钢板在治疗温哥华C型股骨假体周围骨折的生物力学实验中的表现,来分析锁定钢板相对于股骨假体柄远端的位置与产生的刚度和应力集中情况的关系。 方法选取10对成人新鲜股骨标本,随机均分为四组,制作温哥华C型股骨假体周围骨折模型,以四种不同长度的锁定钢板固定:A组,钢板最近端双皮质锁定螺钉距离假体尖端1个股骨直径;B组,钢板最近端双皮质锁定螺钉与假体尖端平齐;C组,钢板最近端单皮质锁钉与假体尖端重叠1个股骨直径;D组,钢板最近端单皮质锁钉与假体尖端重叠2个股骨直径。分别进行轴向压载实验、扭转实验、内外四点侧弯实验及前后四点侧弯实验,记录各组数据并进行统计学分析;最后进行循环负载实验,记录骨折情况。 结果各组在各实验中表现出的刚度值有显著差异,D组刚度值最大(P<0.05);在循环负载实验中,D组骨折线分布于股骨假体尖端、近端锁钉以及钢板远端附近,A、C组的骨折线集中在近端锁钉与股骨假体尖端之间,B组骨折线集中在股骨假体尖端与钢板顶端的线性区域内,结果显示D组应力集中程度比A、B、C三组低(P<0.05)。 结论在使用锁定钢板治疗温哥华C型股骨假体周围骨折时,随着钢板长度增加,内固定稳定性提高;锁定钢板与股骨假体柄尖端重叠固定不会增加应力集中,反而随着钢板与股骨假体重叠区域增加,应力显著分散。  相似文献   
102.

Introduction

The introduction of fixed-angle plate osteosynthesis techniques has provided us a further means to treat periprosthetic femoral fractures. The goal of this experimental study is to evaluate the biomechanical properties and stability of treated periprosthetic fractures when using two different plate systems, which vary in the locking mechanism and the screw placement (monocortical or bicortical) with respect to the prosthesis stem.

Materials and methods

Using five pairs of formalin-fixed femora, a Vancouver B1 periprosthetic fracture was treated either with a 13-hole LISS® titanium plate using four monocortical periprosthetic screws or with a non-contact bridging plate (NCB) DF® plate using bicortical angle-stable blocked screws positioned ventrally or dorsally to the prosthesis stem. Bones were loaded under axial and cyclic compression with a progressively increased load until failure. Displacement at the osteotomy gap was measured during loading using an ultra-sound measuring system.

Results

The mean displacement in the region of the fracture gap was not significantly different at any time during the experiments for the two models. The mean force resulting in subsequent model failure was similar in both models; the failure morphology varied slightly between the models, however. Four of the five LISS® models exhibited either a tear-out of the monocortical screws or a decortication from the bony shaft of the cortical lamella surrounding the screws. On the other side, two of the NCB models showed macroscopically visible fissures along the osteosynthesis plates at the height of the osteotomy gap, and were hence considered implant failures. Only one NCB model showed tear-out of the bicortically placed screws.

Conclusion

Bicortical screw placement provides more stable anchoring when compared to monocortical screw fixation. However, in relation to the amount of motion at the osteotomy gap and to failure loads, stabilisation of periprosthetic femoral fractures can be equally well achieved using either the LISS® plate with periprosthetic monocortical screws or the NCB plate with poly-axially placed bicortical screws.  相似文献   
103.

目的  通过制定、执行深度烧伤手康复路径,评估其对烧伤手切削痂植皮术后患者康复效果的影响。方法  选择2012年1月-2013年12月深度烧伤手采用早期切削痂+自体中厚皮移植的成年患者43例,随机分为对照组和实验组。对照组患者采用手烧伤常规护理、教育督促和接受患者咨询的方式实施康复;实验组患者从瘢痕预防、运动与功能康复、健康教育和心理支持4个主要范畴制定康复路径表,专人按康复路径实施各阶段的康复和指导,并定时电话随访。两组患者使用密歇根手功能量表(MHQ)、温哥华瘢痕量表(VSS)、焦虑自评量表(SAS),分别评估伤后1、3和6个月的患手整体功能、瘢痕情况和心理状态,并进行比较。结果  实验组患者1、3和6个月的MHQ、VSS、SAS总得分优于对照组。实验组伤后1、3和6个月的MHQ总得分比对照组高(P <0.01);VSS总得分比对照组低(P <0.01);SAS得分比对照组低(P <0.01)。结论  手深度烧伤康复路径的实施能有效地提高烧伤手的整体功能,降低瘢痕严重程度,改善患者的心理状态。

  相似文献   
104.
105.
106.
Twenty-one patients with fresh full-thickness burns received a course of two daily applications of sutilains ointment to an area of their burn wound not exceeding 9 per cent of the body surface. Twelve had a mirror-image control burn site of equivalent depth and extent, which was treated identically except sutilains applications were omitted. Good débridement, defined as a wound free of adherent eschar, was observed in 9 patients (43 per cent). The remaining patients' wounds had adherent eschar at the end of the test, or demonstrated equal débridement of both the test and control site. Good débridement was not promoted by increasing the frequency of wet dressings between sutilains applications. Débridement was better in patients receiving more than 8 days of applications. A higher percentage of patients receiving silver sulphadiazine demonstrated good débridement than those receiving gentamicin or no topical antibacterial agent. Burn wound bacterial colonization pattern in sutilainstreated patients did not vary from that observed in those patients receiving only topical antibacterial agents alone.Histological examination revealed that areas with good débridement showed an intense inflammatory cell response and dissolution of the elastic fibres. Control sites and areas with poor débridement showed a lesser inflammatory response and preservation of elastic fibres. No explanation for the variable response to sutilains was apparent histologically. Because of pain associated with application, cost and the unpredictability, sutilains should not be used indiscriminately without monitoring its response carefully and should be used only in conjunction with a topical antibacterial.  相似文献   
107.
Cardiac Pacemakers, Inc. (CPI) solid-state, lithium-powered pulse generators were implanted in 100 patients by one surgeon in a twenty-eight-month period. Eleven CPI pacer generators were replaced, none due to pacer failure. Ninety-nine percent of the patients were followed for a total of 1,397.55 patient-months; 12 patients died, but no deaths appeared to be pacemaker related. The average age of the patients at the time of implantation was 72.8 years. If the warranty period of six years is achieved, the number of pacemaker generator changes required by many of the patients in this group could foreseeably be zero.  相似文献   
108.
The periodic administration of any of a number of convulsive agents has been reported to produce a progressive increase in the severity of the elicited motor seizures (kindling), whereas an elevation in the seizure threshold is the widely reported consequence of a series of electroconvulsive shocks. However, in the present experiments electroconvulsive shocks administered once every 3 days to rats at either of two suprathreshold intensities produced a progressive increase in the severity of the motor seizure pattern. At short intervals (1 hr) the usual decline in motor seizure severity was observed whereas there were no systematic changes at an intermediate interval (1 day). Thus, periodic electroconvulsive shocks produce progressive effects comparable to those produced by the periodic application of other convulsive agents.  相似文献   
109.
Patients undergoing open-heart operations are subject to morbidity related to the use of extracorporeal circulation. Peripheral experience gained from its use can be brought together to enable some of the operations to be performed without subjecting the patient to cardiopulmonary bypass.Right coronary and left anterior descending coronary artery grafting with vein or internal mammary artery can be done on the beating, functioning heart by stabilizing the distal anastomotic site with transfixion sutures and by perfusing the obstructed coronary artery from its own aorta through a cannula which also acts as a stent at the site of anastomosis. High oxygenation levels offer protection to the manipulated heart, and the use of heparin appears to ensure patency of the graft at operation.A series of 63 patients is reported in which there was no mortality related to the cardiac operation and only 1 death related to a presumed cerebrovascular accident. Cardiopulmonary bypass support was not required in any patient selected for this technique.  相似文献   
110.
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