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61.
Injury to the accessory nerve results in an obvious shoulder droop, loss of shoulder elevation, and pain. Prevention of inadvertent injury to the accessory nerve is critical in neck dissection. No previous study, however, anatomically demonstrates the mechanism of the spinal accessory nerve traction injury. Anatomic determination of the location and course of the spinal accessory nerve may be helpful for a better understanding of the mechanism of the nerve injury. The accessory nerve courses obliquely across the posterior triangle on the surface of the levator scapula muscle and reaches the trapezius. The length of the spinal accessory nerve in the posterior triangle is 34.7+/- 6.3 mm. The nerve passes through the posterior border of the sternocleidomastoid muscle 50.7+/- 12.9 mm below the tip of the mastoid process and reaches the anterior border of the trapezius 49.8 +/- 5.9 mm above the clavicle. It makes a posterior angle of 73.1 degrees +/- 19.4 degrees, on average, relative to the posterior border of the sternocleidomastoid. When the shoulder is pulled down and the head is turned to the opposite direction, the spinal accessory nerve is stretched in the posterior triangle. In the posterior triangle, the nerve is vulnerable, since it is superficial and covered only by skin and subcutaneous fascia. Therefore, extreme caution should be taken with any surgical procedures in the posterior triangle. Traction injury of the spinal accessory nerve in the posterior triangle cannot be ignored.  相似文献   
62.
Chest wall resections and reconstruction: a 25-year experience   总被引:11,自引:0,他引:11  
Background. Chest wall defects continue to present a complicated treatment scenario for thoracic and reconstructive surgeons. The purpose of this study is to report our 25-year experience with chest wall resections and reconstructions.

Methods. A retrospective review of 200 patients who had chest wall resections from 1975 to 2000 was performed.

Results. Patient demographics included tobacco abuse, hypertension, diabetes mellitus, alcohol abuse, coronary artery disease, chronic obstructive pulmonary disease, and human immunodeficiency virus. Surgical indications included lung cancer, breast cancer, chest wall tumors, and severe pectus deformities. Twenty-nine patients had radiation necrosis and 31 patients had lung or chest wall infections. The mean number of ribs resected was 4 ± 2 ribs. Fifty-six patients underwent sternal resections. In addition 14 patients underwent forequarter amputations. Immediate closure was performed in 195 patients whereas delayed closure was performed in 5 patients. Primary repair without the use of reconstructive techniques was possible in 43 patients. Synthetic chest wall reconstruction was performed using Prolene mesh, Marlex mesh, methyl methacrylate sandwich, Vicryl mesh, and polytetrafluoroethylene. Flaps utilized for soft tissue coverage were free flap (17 patients) and pedicled flap (96 patients). Mean postoperative length of stay was 14 ± 14 days. Mean intensive care unit stay was 5 ± 9 days. In-hospital and 30-day survival was 93%.

Conclusions. Chest wall resection with reconstruction utilizing synthetic mesh or local muscle flaps can be performed as a safe, effective one-stage surgical procedure for a variety of major chest wall defects.  相似文献   

63.
Deep K  Jigajinni MV  Fraser MH  McLean AN 《Injury》2002,33(4):353-355
AIM: Survey and discussion of the current thromboembolic prophylaxis practice in spinal injury units within the British Isles. BACKGROUND: Deep vein thrombosis and pulmonary embolism are major causes of morbidity and mortality in patients with spinal injuries. A wide range of thromboprophylactic measures have been proposed. The optimum treatment and duration for thromboprophylaxis in spinal injuries is unknown. Different spinal units within the British Isles use different measures despite similar training backgrounds. The present study was performed to review practice and make suggestions on best practice using literature review. METHODS: All the 13 regional and national spinal injury referral centres within the British Isles were contacted to find out their protocols for thromboembolic prophylaxis in patients with acute spinal injuries. RESULTS: All units replied. A wide variation in methods used was found in different spinal units ranging from no chemical prophylaxis to oral anticoagulation with warfarin and contrasting views on the use of antithromboembolic stockings. CONCLUSION: All units recognised the risk of thromboembolism after spinal injuries. A wide variety of thromboprophylactic measures are used.  相似文献   
64.
Thaveau F  Zoll J  Rouyer O  Chafke N  Kretz JG  Piquard F  Geny B 《Journal of vascular surgery》2007,46(3):541-7; discussion 547
OBJECTIVE: Defective mitochondrial function has been reported in patients presenting with peripheral arterial disease, suggesting it might be an important underlying mechanism responsible for increased morbidity and mortality. We therefore determined the effects of prolonged ischemia on energetic skeletal muscle and investigated whether ischemic preconditioning might improve impaired electron transport chain and oxidative phosphorylation in ischemic skeletal muscle. METHODS: Thirty rats were divided in three groups: the control group (sham, n = 9) underwent 5 hours of general anesthesia without any ischemia, the ischemia-reperfusion (IR) group (n = 11) underwent 5 hours ischemia induced by a rubber band tourniquet applied on the left root of the hind limb, and in the third group, preconditioning (PC group, n = 10) was performed just before IR and consisted of three cycles of 10 minutes of ischemia, followed by 10 minutes reperfusion. Maximal oxidative capacities (V(max)) of the gastrocnemius muscle and complexes I, II, and IV of the mitochondrial respiratory chain were determined using glutamate-malate (V(max)), succinate (V(s)), and N, N, N,'N'-tetramethyl-p-phenylenediamine dihydrochloride ascorbate as substrates. RESULTS: Physiologic characteristics were similar in the three groups. Ischemia reduced V(max) by 43% (4.5 +/- 0.4 vs 7.9 +/- 0.5 micromol O(2)/(min x g dry weight), P < .01) and V(s) by 55% (2.9 +/- 0.3 vs 6.3 +/- 0.4 micromol O(2)/min/g dry weight; P < .01) in the IR and sham groups, respectively, and impairments of mitochondrial complexes I and II activities were evident. Of interest was that preconditioning prevented ischemia-induced mitochondrial dysfunction. Both V(max) and V(s) were significantly higher in the PC rats than in IR rats (+32% and +41%, respectively; P < .05), and were not different from sham values. CONCLUSIONS: Ischemic preconditioning counteracted ischemia-induced impairments of mitochondrial complexes I and II. These data support that ischemic preconditioning might be an interesting approach to reduce muscular injuries in the setting of ischemic vascular diseases.  相似文献   
65.
BACKGROUND: Familial aggregation of IgA nephropathy (IgAN) suggests that genetic factors contribute to the development of this trait. Because clinical manifestations in IgAN families are often limited to episodic haematuria, large kindreds tractable to linkage analysis have been difficult to identify. METHODS: We identified a large Lebanese-Druze kindred ascertained via an index case with biopsy-documented IgAN. We performed systematic screening of 38 family members and tested linkage to reported IgAN loci. RESULTS: Screening of this family identified 16 affected individuals, including 2 individuals with biopsy-documented IgAN and 14 with chronic renal failure or abnormal urinalyses on at least three separate occasions. This kindred spanned five generations and contained five consanguineous unions. Multigenerational inheritance suggested that autosomal dominant inheritance was most likely. Phenotypic manifestations among affected individuals varied from isolated haematuria to advanced renal failure necessitating transplantation; one instance of IgAN recurrence after transplantation was also documented. Older age was associated with greater severity of disease and higher incidence of renal failure. Parametric and non-parametric analyses with 33 microsatellite markers did not reveal any evidence of linkage to reported IgAN loci on chromosomes 6q22-23, 2q36 and 4q22-31. CONCLUSIONS: We describe one of the largest multigenerational IgAN kindreds reported to date. The high incidence of renal failure among older generations suggests a significant risk of progression to renal failure. We found no evidence of linkage to known loci, suggesting that familial IgAN encompasses multiple subtypes that will require distinction based on genetic or biomarker data.  相似文献   
66.
Traditional classifications for skin treatment modalities are based on skin characteristics, the most important being skin color. Other factors are considered as well, such as oiliness, thickness, pathology, and sensitivity. While useful, these classifications are occasionally inadequate in predicting and explaining the outcome of some peels, dermabrasions, or laser resurfacing procedures. Why, for example, would a Korean patient with a light white skin inadvertently develop more hyperpigmentation than his darker skinned French counterpart? The new classification introduced here is based on the racial and genetic origins of patients. It suggests that racial genetic predisposition is the determining factor in human response to skin injury, including skin treatments. This classification takes into account both skin and features, rather than skin alone. It offers a new approach in evaluating patients scheduled for skin peels or laser resurfacing, in the hope of helping physicians to better predict reactions, select the appropriate type and intensity of the skin treatment and, ultimately, better control the outcome. Six categories (sub-races) are described: Nordics, Europeans, Mediterraneans, Indo-Pakistanis, Africans, and Asians. The reaction of each sub-race to peels, laser resurfacing, or dermabrasion is analyzed. The risks associated with each group are noted. This new classification provides physicians with a practical way to evaluate patients prior to treatment, with a view to determining each patient's suitability, postoperative reaction, the likelihood of complications, and likely result.  相似文献   
67.
Postoperative cardiac tamponade in the modern surgical era   总被引:2,自引:0,他引:2  
BACKGROUND: Pericardial effusions resulting in cardiac tamponade (CT) are uncommon after open heart surgery (OHS) and are associated with significant morbidity and mortality. Characteristics and outcomes of patients who develop postoperative CT are poorly defined. Our objective was to further analyze the population at risk for developing postoperative CT, identify potential perioperative and surgical risk factors, and evaluate the impact of CT on patient outcomes. METHODS: A retrospective analysis of 4,561 consecutive patients undergoing OHS at our institution was performed. Patients with clinical suspicion of pericardial effusion following surgery were evaluated by transthoracic or transesophageal echocardiography, and clinical parameters were analyzed. RESULTS: Forty-eight (1%) of the 4,561 patients were found to have echocardiographic evidence of a moderate or large pericardial effusion, of whom 36 (74%) had evidence of CT. The mean age of the patients with CT was 61 years. Coronary artery bypass grafting (CABG) had been performed in 24% of these patients, valve +/- CABG in 73%, and other OHS procedures in 3%. The incidence of CT following CABG alone was 0.2%, whereas it was 0.6% after valve +/- CABG. Females had a higher risk for developing CT, and this occurred earlier in the postoperative period when compared with men. Aspirin, heparin, or warfarin were given to 84% of patients within 3 days of surgery. Mean time to diagnosis of CT was 10 +/- 1 days after OHS. Prior to diagnosis of CT, the maximum international normalized ratio (INR) and partial thromboplastin time (PTT) were 2.7 +/- 0.3 and 68 +/- 5 seconds, respectively. Forty-nine percent of pericardial effusions were posterior and 46% were circumferential; one-third of the effusions were considered large by echocardiography. There was one in-hospital cardiovascular death. CONCLUSIONS: CT after OHS is more common following valve surgery than CABG alone and may be related to the preoperative use of anticoagulants. Females appear to be at higher risk for developing early postoperative CT. When diagnosed and treated promptly, postoperative CT should not significantly increase mortality.  相似文献   
68.
The spontaneous and simultaneous rupture of both quadriceps tendons is uncommon and has rarely been reported in the literature. The current case involves a 43-year-old man with end-stage renal disease requiring hemodialysis for the past 20 years. The patient experienced bilateral knee pain and swelling and was unable to bear weight. Physical examination revealed bilateral quadriceps tendon defect above the patella and loss of active extension. Although plain radiographs of both knees showed no fracture or widening of the joint space, an inferiorly positioned patella was observed. Ultrasonography of the knees revealed a quadriceps tendon defect at the upper edge of each patella, while MR imaging revealed a tear in each quadriceps tendon from the superior poles of the patella. The patient then underwent surgical correction wherein the tendons were repaired using sutures passed through drill holes in the patella. The knees were immobilized with splints for 4 wk before starting physiotherapy. The patient subsequently regained full functional activity within 1 year.  相似文献   
69.

Background

Understanding the risk factors for local and in-transit recurrences (LR/ITR) may help facilitate methods of prevention, early detection, and treatment.

Methods

A retrospective review of a prospectively collected database was performed on patients diagnosed with single-lesion cutaneous melanoma. Clinical and pathologic characteristics of the tumors were evaluated.

Results

Of 225 patients, 10% had LR/ITR. Patients with LR/ITR were older (P = .0002), had thicker tumors (P = .018), and positive angiolymphatic invasion more frequently (P < .0001). An increased tumor mitotic rate (TMR) was more common in LR/ITRs (P = .051). On univariate logistic regression, age, thickness, TMR of 11/mm2 or greater, and angiolymphatic invasion were all significant risk factors for LR/ITR. Multivariate logistic regression showed age, thickness, and angiolymphatic invasion were the only significant risk factors.

Conclusions

Older patients with thicker tumors and angiolymphatic invasion appear to be at higher risk for LR/ITR. Such patients warrant consideration of preventative strategies and should receive close clinical follow-up evaluation for early recurrence.  相似文献   
70.

Background

This open-label study compared oral or intravenous linezolid with intravenous vancomycin for treatment of complicated skin and soft-tissue infections (cSSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA).

Methods

Patients with proven MRSA cSSTI were randomized to receive linezolid or vancomycin. Clinical and microbiologic outcomes, duration of antimicrobial therapy, length of hospital stay, and safety were assessed.

Results

In the per-protocol population, the rate of clinical success was similar in linezolid- and vancomycin-treated patients (P = .249). The rate of success was significantly higher in linezolid-treated patients in the modified intent-to-treat population (P = .048). The microbiologic success rate was higher for linezolid at the end of treatment (P < .001) and was similar at the end of the study (P = .127). Patients receiving linezolid had a significantly shorter length of stay and duration of intravenous therapy than patients receiving vancomycin. Both agents were well tolerated. Adverse events were similar to each drug's established safety profile.

Conclusions

Linezolid is an effective alternative to vancomycin for the treatment of cSSTI caused by MRSA.  相似文献   
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