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71.
Abstract The objective of the study was to evaluate the precision, concordance, practicability and the early clinical outcome of the use of a computerised navigation system in a comparative study with a group of 100 patients. Two groups of 50 patients each underwent implantation of a bicondylar knee prosthesis either by means of the freehand navigation system or by means of technical instrumentation. We found that the computerised navigation system provided a higher precision than the technically instrumented implantation: 94% of the prostheses implanted with the navigation system have an alignment within a range of -3° to 3° on of the Mikulicz line. Only 46% of the patients operated by means of the technical instrumentation reached this aspired result. Furthermore, the navigation system showed smaller ranges in the deviation of the aspired alignment. The radiological and computer-modeled alignment values differed both pre- and postoperatively, but to a larger extent before surgery. The varus or valgus deviations of the axis were more distinct radiologically under the weight of the patient’s body than in the computer model. The clinical outcome examined by the use of the HSS score after a mean followup of 7 months is good in both groups, and without significant differences. On average, the duration of surgery was 13 minutes longer in the computerised navigation group. We conclude that the benefit of the computerised navigation system is represented by the high improvement of precision. Achieving early clinical results identical to those in the technical instrumentation group, we expect a reduction of aseptic loosening in the computerised navigation group.  相似文献   
72.
BACKGROUND: The benefit-to-risk ratio of vitamin K antagonists (VKA), relative to active comparators, especially low-molecular-weight heparins (LMWH), for preventing venous thromboembolism in patients undergoing major orthopedic surgery is debated. OBJECTIVES: We performed a meta-analysis of all randomized trials in orthopedic surgery comparing adjusted doses of VKA to control treatments. PATIENTS AND METHODS: An exhaustive literature search, both manual and computer-assisted, was performed. Studies were selected on the basis of randomization procedure (VKA vs. a control group). At least one of the following outcome measures was to be evaluated: deep vein thrombosis (DVT), pulmonary embolism (PE), death, major hemorrhage or wound hematoma. Four reviewers assessed each article to determine eligibility for inclusion and outcome measures. RESULTS: VKAs were more effective than placebo or no treatment in reducing DVT [567 patients, relative risk (RR) = 0.56, 95% confidence interval (CI) 0.37, 0.84, P < 0.01] and clinical PE (651 patients, RR = 0.23, 95% CI 0.09, 0.59, P < 0.01). These results were obtained at the cost of a higher rate of wound hematoma (162 patients, RR = 2.91, 95% CI 1.09, 7.75, P = 0.03). VKAs were also more effective than intermittent pneumatic compression (534 patients, RR = 0.46, 95% CI 0.25, 0.82, P = 0.009) in preventing proximal DVT. In contrast, VKAs were less effective than LMWH in preventing total DVT and proximal DVT (9822 patients, RR = 1.51, 95% CI 1.27, 1.79, P < 0.001; and 6131 patients, RR = 1.51, 95% CI 1.04, 2.17, P = 0.028, respectively). The differences between VKA and LMWH in major hemorrhage and wound hematoma were not significant. CONCLUSIONS: In patients undergoing major orthopedic surgery, VKAs are less effective than LMWH, without any significant difference in the bleeding risk.  相似文献   
73.
74.
BACKGROUND: Basal cell carcinoma (BCC) is a non-melanoma form of skin cancer that is frequently localized within the cervicofacial area. So far, little research is available on how patients perceive their facial aesthetics after surgical treatment for BCC. OBJECTIVES: To analyse (i) if there was a statistically significant improvement over time with regard to the perceived facial aesthetics of surgical patients; (ii) if there was a significant difference between primary and recurrent BCC patients; and (iii) between patients who had Mohs micrographic surgery (MMS) or surgical excision (SE). To assess (iv) which baseline perceptions and/or clinical parameters may predict the evaluation of facial aesthetics at 6 months after surgery. METHODS: Parallel to a clinical trial, a survey was carried out in which patients were asked, by means of a newly developed disease-specific questionnaire, about perceptions with regard to their facial aesthetics before and after surgery. RESULTS: Aesthetic perceptions of all surgical patients improved over time. There was no statistically significant difference on facial aesthetics between the group with a primary or recurrent BCC and patients treated with MMS or SE. Results also showed that the evaluation of postsurgical facial aesthetics can be predicted by both visibility of the tumour and preoperative perceptions. CONCLUSION: It is recommended to administer preoperatively a short questionnaire in which perceptions related to facial aesthetics are included. In doing so, physicians will become more familiar with the aesthetic problems patients might have regarding their afflicted facial site. Ultimately, it may help physicians in deciding whether patients will benefit from additional cosmetic procedures after surgery.  相似文献   
75.
98例尿道下裂手术的体会   总被引:1,自引:0,他引:1  
目的通过对尿道下裂手术的改进,进一步完善尿道下裂手术的技巧和护理。方法A组50例尿道下裂Ⅰ期成形术中,采用皮下连续内翻缝合形成新尿道,且固定于阴茎海绵体,由阴茎根部自下而上多层次,多点缝合皮瓣皮下组织至阴茎海绵体上,均无间隙和死腔。B组48例采用常规手术方式作对照。结果A组50例尿道下裂Ⅰ期成形术成功44例,B组48例成功17例,A组与B组相比成功率显著提高(P<0.05)。结论尿道下裂Ⅰ期成形术成功率关键在于术者对术式掌握的熟练程度和术中及术后对每个细节的认真处理。  相似文献   
76.
OBJECTIVE: To describe the dieting histories of bariatric surgery candidates. RESEARCH METHODS AND PROCEDURES: One hundred seventy-seven individuals with extreme obesity who sought bariatric surgery completed the Weight and Lifestyle Inventory, a self-report instrument that assesses several variables, including weight and dieting history. Patients' dieting histories were further explored with an aided recall during a preoperative behavioral/psychological evaluation performed by a mental health professional. RESULTS: Participants who completed the Weight and Lifestyle Inventory reported an average of 4.7 +/- 2.9 successful dieting attempts, defined as those that resulted in a loss of 10 lbs (4.5 kg) or more. These individuals reported a mean total lifetime weight loss of 61.1 +/- 41.3 kg. Despite these efforts, their weight increased from 89.4 +/- 27.4 kg at the time of their first diet (age 21.2 +/- 10.1 years) to 144.5 +/- 30.8 kg at the time they underwent their behavioral/psychological evaluation (age 43.0 +/- 11.0 years). Results of the aided recall revealed that participants had made numerous other efforts to lose weight that were unsuccessful. Self-directed diets and commercial programs were used more frequently. DISCUSSION: Individuals who sought bariatric surgery reported an extensive history of dieting, beginning in adolescence, that was not successful in halting progressive weight gain. Thus, the recommendation often made by insurance companies that patients delay surgery to attempt more conservative treatment options may be unwarranted, particularly in the presence of significant obesity-related comorbidities. Weight loss histories should be routinely examined during a behavioral evaluation to determine whether additional attempts at non-surgical weight loss are advisable. Future studies also are needed to explore the potential relationship between dieting history and postoperative outcome.  相似文献   
77.
关节镜辅助下微创经皮螺钉内固定治疗胫骨平台骨折   总被引:5,自引:0,他引:5  
目的:探讨关节镜辅助下微创经皮螺钉内固定治疗胫骨平台骨折的可行性及疗效。方法:自2001年1月-2005年1月,应用膝关节镜检查及监测下经皮螺钉内固定治疗胫骨平台骨折27例,按照Schatzker分类法:Ⅰ型9例,Ⅱ型8例,Ⅲ型5例,Ⅳ型5例。所有病例均行经皮骨折有限显露复位,适当植骨,应用1~3枚松质骨拉力螺钉内固定,术后配合CPM功能锻炼。结果:本组随访6~24个月,平均15个月。骨折临床愈合时间3~4个月,平均3·5个月。无畸形愈合、感染、螺钉断裂。按Sanders膝关节功能评分法评定结果:优12例,良11例,中3例,差1例,优良率85·2%。结论:关节镜辅助经皮螺钉内固定是治疗胫骨平台骨折的有效方法之一,其对膝关节创伤小,可达解剖复位,固定可靠,患肢功能恢复好,并发症少。  相似文献   
78.
目的评价腹腔镜与开放性肾囊肿去顶术的临床疗效。方法回顾性分析采用经后腹腔镜和经腹腔镜行肾囊肿去顶术21例,其中经腹腔5例,经后腹腔16例,与开放性手术16例比较。结果手术时间,术中平均出血量,术后下床活动时间,术后住院天数,术后并发症腹腔镜组均优于开放手术组,住院费用腹腔镜组略高于开放性手术组。结论腹腔镜肾囊肿去顶术治疗单纯性肾囊肿安全、有效。应成为治疗单纯性肾囊肿的首选方法。  相似文献   
79.
Knee anterior cruciate ligament reconstructive surgery has significantly evolved and now includes the option of using an allograft. This has resulted in numerous studies evaluating the advantages and disadvantages of allografts. The purpose of this literature review is to evaluate this research and present important findings to allow the selection of the most appropriate graft source when considering allograft versus autograft reconstruction.  相似文献   
80.
Objective: We assessed the current role of preoperative and intraoperative autologous blood donation in pediatric open-heart surgery. Methods: Group 1 consisted of 51 patients between 5 and 10 years old who underwent preoperative autologous blood donation. Group 2 consisted of 50 age-matched patients without preoperative donation as controls. Intraoperative donation was conducted in both groups prior to cardiopulmonary bypass. We evaluated perioperative blood cell count, blood loss, and the need for homologous blood products. Results: No serious complications occurred in preoperative or intraoperative donation. Total preoperative donation storage was 17.5±3.4 mL/kg. Intraoperative donation was 21.7 ±6.1 mL/kg in Group 1 and 12.8±4.0 mL/kg in Group 2 (p<0.001). On admission, serum hemoglobin was lower in Group 1 (12.2±1.0 g/dL versus 13.6±1.6 g/dL, p<0.001) but returned postoperatively to the preoperative value. It hovered at a depressed level in Group 2 (12.2±1.4 versus 10.2±1.1 g/dL, p<0.001). The homologous blood requirement was significantly less in Group 1 than in Group 2 (0% versus 10%, p<0.05). Postoperative platelet counts showed similar curves, and blood loss was not statistically significantly different between groups. Conclusion: Preoperative and intraoperative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive blood conservation programs in current pediatric open-heart surgery.  相似文献   
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