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41.
Bone stock preservation is crucial when performing total hip replacement in young patients. The aim is to save good bone stock
for a possible revision procedure. Furthermore, there is an increasing demand from young and active patients to receive a
new joint which allows a normal or nearly normal life style. With this in mind, we began, in 1993, to develop a new femoral
implant. The purpose of this ultra-short stem was a physiologic strain distribution on the proximal femur with a proximal
load transfer from the implant to the femoral bone. Main features were an almost complete absence of the diaphyseal portion
of the stem, a well defined lateral flare with load transfer on the lateral column of the femur, and a very high femoral neck
cut. These innovations resulted in a conservative implant on both the bone stock and the soft tissues. This implant, in the
first years, was recommended only for young and active patients. Over the last thirteen years, this project has undergone
several modifications but the basic principles of the implant have remained the same. In the present review, we present the
rationale, the surgical technique and the clinical and experimental results so far obtained with this implant. 相似文献
42.
Objective To investigate the clinical effects of total hip arthroplasty (THA) for bony ankylosis in patients with ankylosing spondylitis and the significance of postoperative rehabilitation. Meth-ods From October 1998 to May 2007, 28 patients (46 hips) suffered from ankylosing spondylitis with hip bony ankylosis underwent THA. There were 27 males, 1 female, with the mean age of 38.9 years (range 22 to 58 years). Posterior lateral hip incision was performed in 34 hips, and modified anterior lateral combined with lateral hip incision in 12 hips. Forty hips applied cementless THA and 6 hips applied mixed THA. Har-ris scores, VAS scores and total hip range of motion in all patients were compared pre-and postoperatively to evaluate the clinical effects. Results All patients were followed up from 10 months to 64 months, with the mean time of 38.2 months. No paralysis, decubitus, and lung infection were found. Joint dislocation hap-pened in 1 case 2 weeks after operation, and was cured with close reduction. Heterotopic bone formation with Brooker Ⅰ was found in 6 hips and Brooker Ⅱ in 2 hips. Harris score increased from 28.3±10.3 preop-eratively to 82.7±7.6 postoperatively. VAS score changed from 3.5±1.4 preoperatively to 3.8±1.8 postopera-tively, and no significance was found. The hip movement range increased from 15.6°±9.3° preoperatively to 133.7°±17.6° postoperatively. Bony ankylosis in all patients disappeared and the hip function improved sig-nificantly after operation. Conclusion THA is the optimal method to treat the ankylosing spondylitis with hip bony ankylosis. Early rehabilitation is necessary to improve hip function. 相似文献
43.
Early micromotion of implant components and periprosthetic bone loss in patients undergoing total knee arthroplasty are thought
to contribute to late aseptic loosening. In the pursuit of longer implant survival, the administration of bisphosphonates
may be advocated as a means to buffer implants against microinstability and periprosthetic bone loss. A bibliographic search
identified one metaanalysis and two randomised controlled trials dealing with this topic. Current evidence supports the hypothesis
that the inhibiting effects of bisphosphonates on bone resorption reduce implant micromotion and periprosthetic bone loss
at the one-year follow-up. Tested bisphosphonates include clodronate, pamidronate and alendronate. However, a decline in periprosthetic
BMD is observed at the three-year follow-up following a sixmonth course of bisphosphonate administration. Length of follow-up
in available studies is currently too short to determine whether bisphosphonates increase the longevity of implants. Furthermore,
the optimal dose, modality and length of bisphosphonate administration have yet to be determined. 相似文献
44.
Ashutosh Singh M.Ch. Vidyut Kumar Sinha M.Ch. Jayant Khandekar M.Ch. Nandkishor Agrawal M.Ch. Anil Patwardhan M.Ch. Dr. Jagdish Kharideparkar M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(2):121-125
Objective The degree of Left Ventricular Mass Index (LVMI) regression following aortic valve replacement correlates with long-term survival.
This study aims to assess the extent of LVMI regression at 3 months following aortic valve replacement (AVR) with different
types and sizes of mechanical valves in rheumatic aortic valve disease.
Methods The LVMI regression was studied in 34 consecutive patients, undergoing elective AVR for rheumatic aortic stenosis and/or regurgitation.
They were grouped in A and B, matched in age, body surface area and pre-operative LVMI, receiving respectively a tilting disc
and a bileaflet mechanical valve. The LVMI was calculated by M-mode echocardiography using the Devereux' formula pre-operatively
and three months post-operatively. The trend of LVMI reduction was compared between the two groups and amongst the patients
with stenotic, regurgitant and mixed aortic valve, pathologies; and receiving different sizes of valves.
Results The mean preoperative LVMI was 199g±79.5 g/m2. At three months post aortic valve replacement, the mean LVMI was 130g±49.0 g/m2. There was a significant reduction of LVMI post-operatively (p=0.001) at three months follow-up. The extent of LVMI regression
following surgery amongst the groups A and B did not vary significantly (p=0.92). The extent of LVMI regression did not vary
significantly in patients with different aortic valve pathology nor with different sizes of the valves implanted.
Conclusions There is a significant early LVMI regression following aortic valve replacement in rheumatic aortic valve disease. The type
and the size of the mechanical prosthesis or the rheumatic pathology do not appear to influence this regression. 相似文献
45.
D.A. Legemate P.M. Bossuyt 《European journal of vascular and endovascular surgery》2006,32(6):620-623
There is insufficient evidence that the surgical treatment of asymptomatic infrarenal aneurysms > 5.5 cm. is beneficial to patients. This is the result of serious complications of aneurysm surgery and the dearth of information from randomized trials. Based on evidence from the literature we defined scenarios and translated data into natural frequency trees to improve understanding of the uncertainty of help versus harm due to treatment of aneurysms. Our analysis shows that the majority of patients can expect little on longevity from surgery while they are at risk of dying from surgery or suffering from serious morbidity. We conclude that, as long as uncertainty persist, patients should be treated in hospitals that can show very low surgical mortality and major morbidity rates. To further resolve the problem of uncertainty randomized trials for larger aneurysms should be performed. Important issues to discuss are the lower and upper limits of the diameter of the aneurysms and the age and risk profiles of the patients to be included in such trials. 相似文献
46.
Yasuyuki Suzuki Kazuyuki Daitoku Masahito Minakawa Kozo Fukui Ikuo Fukuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(1):44-46
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary
atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation
which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result
in progressive aortic regurgitation for a short period. 相似文献
47.
主要阐述空调水系统利用平衡阀调节系统阻力,保持系统水力稳定;利用软启动器实施水泵的平滑软启动;压差旁通阀的作用及选型安装;系统管道热膨胀等问题。 相似文献
48.
Migration of Kirschner (K) wires from the upper extremity joints has often been reported, but it is less common from the lower
extremities. In this report, we describe an 85-year-old man treated, during a hip replacement procedure, with a K-wire because
of a trochanteric fracture; after one year, the K-wire was found in the popliteal fossa. This report illustrates the first
case of K-wire migration in the popliteal area of the knee and suggests avoiding the use of free K-wires without any tension
banding. 相似文献
49.
目的:对行人工关节置换手术的高龄股骨颈骨折患者进行围手术期综合处理,探讨其围手术期治疗的必要性与重要性。方法:68例股骨颈骨折的高龄患者,男28例,女40例;年龄70~88岁,平均76.4岁。所有患者于关节置换术前采用有效的降糖,降压,营养心肌,保肝,纠正贫血、低蛋白血症等综合处理,控制合并症。患者全身情况、脏器功能状况可耐受手术后行人工关节置换手术。结果:所有患者均安全渡过手术期,切口Ⅰ期愈合。1例术后早期出现腹泻并发症,经应用制霉菌素及金双岐调节肠道菌群,腹泻控制。按Harris标准评价疗效,优39例,良24例,可5例,优良率92.6%。结论:严格有效的围手术期综合治疗是处理高龄股骨颈骨折患者行人工关节置换手术的安全保障。 相似文献
50.
Dr. Menon Raj Gopal M.Ch. AlDelamie Taha FRCS Valliathu John FRCS Zacharias Sunny FRCS Lawati Al Adil FRCS Venkatraman M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):173-177
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth
and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the
performance of valves in this age group.
Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were
implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves
were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position.
Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class
III.
Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow
up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients
have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient.
Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace
valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully
in children, when repair has failed or not technically feasible. 相似文献