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71.

Introduction

The ButtonFix® system represents a new angular stable percutaneous fixation device for stabilisation of fractures of the proximal humerus. The purpose of this study was to present a preliminary report of the radiological and clinical outcome after minimally invasive stabilisation of selected proximal humerus fractures with the ButtonFix®.

Patients and methods

Seventeen patients with fractures of the proximal humerus were treated in our department with the ButtonFix® system. The mean final follow-up was performed 19 months postoperatively. Follow-up included assessment of postoperative reposition, range of motion, the DASH score, the Constant–Murley score, and the Short Form 36 (SF36).

Results

Twelve patients showed anatomical head-to-shaft angles, four revealed minor valgus replacement, and one minor varus replacement. In one patient unplanned revision surgery was necessary due to early secondary fracture dislocation requiring ORIF with an angular stable form plate. Implant removal was performed after 6 weeks in all patients. At the final follow-up, mean range of motion was: flexion 135°, extension 45°, abduction 142°, internal rotation 51°, and external rotation 62°. The mean Constant–Murley score was 70. The mean DASH score was 26 points and the average SF36 score was 76 points. One patient showed radiological signs of avascular necrosis.

Conclusion

The ButtonFix® system represents a valuable tool in the treatment of proximal humeral fractures with results indicating fewer complications compared to prior percutaneous fixation devices. Moreover, the ButtonFix® seems to be able to maintain reduction even in elderly patients with potentially reduced bone mass.  相似文献   
72.
Male reproductive disorders that are of interest from an environmental point of view include sexual dysfunction,infertility,cryptorchidism,hypospadias and testicular cancer. Several reports suggest declining sperm counts and increase of these reproductive disorders in some areas during some time periods past 50 years. Except for testicular cancer this evidence is circumstantial and needs cautious interpretation. However,the male germ line is one of the most sensitive tissues to the damaging effects of ionizing radiation,radiant heat and a number of known toxicants. So far occupational hazards are the best documented risk factors for impaired male reproductive function and include physical exposures (radiant heat,ionizing radiation,high frequency electromagnetic radiation),chemical exposures (some solvents as carbon disulfide and ethylene glycol ethers,some pesticides as dibromochloropropane,ethylendibromide and DDT/DDE,some heavy metals as inorganic lead and mercury) and work processes such as metal welding. Improved working conditions in affluent countries have dramatically decreased known hazardous workplace exposures,but millions of workers in less affluent countries are at risk from reproductive toxicants.New data show that environmental low-level exposure to biopersistent pollutants in the diet may pose a risk to people in all parts of the world. For other toxicants the evidence is only suggestive and further evaluation is needed before conclusions can be drawn. Whether compounds as phthalates,bisphenol A and boron that are present in a large number of industrial and consumer products entails a risk remains to be established. The same applies to psychosocial stressors and use of mobile phones. Finally,there are data indicating a particular vulnerability of the fetal testis to toxicants-for instance maternal tobacco smoking. Time has come where male reproductive toxicity should be addressed form entirely new angles including exposures very early in life.  相似文献   
73.
Background: Volatile anesthetics are commonly used for general anesthesia. However, these can induce profound cardiovascular alterations. Xenon is a noble gas with potent anesthetic and analgesic properties. However, it is uncertain whether xenon alters myocardial function. The aim of this study was therefore to investigate left ventricular function during anesthesia with xenon compared with isoflurane.

Methods: The authors performed a randomized multicenter trial to compare xenon with isoflurane with respect to cardiovascular stability and adverse effects in patients without cardiac diseases scheduled for elective surgery. Two hundred fifty-nine patients were enrolled in this trial, of which 252 completed the study according to the protocol. Patients were anesthetized with xenon or isoflurane, respectively. Before administration of the study drugs and at four time points, the effects of both anesthetics on left ventricular function were investigated using transesophageal echocardiography.

Results: Global hemodynamic parameters were significantly altered using isoflurane (P < 0.05 vs. baseline), whereas xenon only decreased heart rate (P < 0.05 vs. baseline). In contrast to xenon, left ventricular end-systolic wall stress decreased significantly in the isoflurane group (P < 0.05 vs. baseline). Velocity of circumferential fiber shortening was decreased significantly in the xenon group but showed a more pronounced reduction during isoflurane administration (P < 0.05 vs. baseline). The contractile index (difference between expected and actually measured velocity of circumferential fiber shortening) as an independent parameter for left ventricular function was significantly decreased after isoflurane (P < 0.0001) but unchanged using xenon.  相似文献   

74.
Background: Anesthesia is associated with complications, and some of them may be fatal. The authors investigated the circumstances under which deaths were associated with anesthesia. In Denmark, the specialty anesthesiology encompasses emergency medicine, chronic and acute pain medicine, anesthetic procedures, perioperative care medicine, and intensive care medicine.

Methods: The authors retrospectively investigated anesthesia related deaths registered by the Danish Patient Insurance Association.

Results: From 1996 to 2004, 27,971 claims were made by the Danish Patient Insurance Association covering all medical specialties, of which 1,256 files (4.5%) were related to anesthesia. In 24 cases, the patient's death was considered to result from the anesthetic procedure: 4 deaths were related to airway management, 2 to ventilation management, 4 to central venous catheter placement, 4 as a result of medication errors, 4 from infusion pump problems, and 4 after complications from regional blockades. Severe hemorrhage caused 1 death, and in 1 case the cause was uncertain.  相似文献   

75.
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA). Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm results were obtained through clinical investigation and magnetic resonance angiography imaging. Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group and 29 patients from the AAA group (82.9%) were alive. Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms.  相似文献   
76.
Many children with a late steroid-resistant nephrotic syndrome (SRNS) and focal glomerulosclerosis have a poor prognosis and enter end-stage renal failure (ESRF) within five years. Reports are scarce on the long-term follow-up of patients entering remission while receiving immunosuppressive therapy after steroids have failed. A two-year-old boy with focal and segmental glomerulosclerosis having both late steroid and cyclophosphamide resistance entered complete remission of the SRNS almost two years after starting induction therapy with cyclosporine A (CSA). During the 15-year follow-up, the patient experienced five relapses during CSA maintenance therapy. All relapses were successfully treated within 10 days by intravenous methylprednisolone pulses in addition to CSA. The relapses were accompanied by a drop in the glomerular filtration rate (GFR). At the age of 18 years, the patient had grade II chronic kidney disease (GFR=61 ml/min/1.73 m2). At the age of 14 years, mycophenolate mofetil (MMF) was added to the maintenance therapy and the CSA dosage was reduced. Two renal biopsies at the ages of 10 and 18 years failed to detect CSA nephrotoxicity. We conclude that children with SRNS may have long-term benefit from a combination therapy using intravenous methylprednisolone pulses and CSA.  相似文献   
77.
Examination is a cornerstone in the manual procedures leading to mobilisation/manipulation of the low back. The observer variation of the more specific segmental tests remains to be investigated. Two skilled specialists in manual medicine examined the segmental changes in the lumbar spine. The patients were unknown to the examiners and no information of the case history was given. All test results were recorded by an observer present in the room who ensured that no conversation was allowed during the examination. The primary outcome measures were the kappa values for each test. The matching was defined as acceptable (acc) within two neighbouring levels and perfect (per) on the same level. Intra-observer variation (tested in 33 patients and 10 subjects without low-back pain): The agreement between first and second segmental diagnosis examination was 70% (per) and 82% (per + acc). Kappa values were: segmental diagnosis 0.60 (per) and 0.70 (per + acc), multifidus test 0.51 (per) and 0.60 (per + acc), sideflexion 0.57 (per) and 0.69 (per + acc), and ventral flexion 0.31 (per) and 0.45 (per + acc). Inter-observer variation (tested in 60 patients): The agreement for segmental diagnosis between the examiner A and B was 42% (per) and 75% (per + acc). Kappa values were: segmental diagnosis 0.21 (per) and 0.57 (acc), multifidus test 0.12 (per) and 0.48 (acc), sideflexion 0.22 (per) and 0.45 (acc), and ventralflexion 0.22 (per) and 0.44 (acc). By manual tests, skilled examiners seem to be able to diagnose segmental dysfunctions in the low back. The clinical implication of these dysfunctions remains to be clarified.  相似文献   
78.
A 49-year-old woman presented with acute abdominal pain in the right iliac fossa in our emergency department. Pain was abrupt in onset and severely colicky in nature. Abnormal laboratory values included a C-reactive protein of 75 mg/L and a CA-125 of 70.3 U/mL. White blood cell count was normal. Abdominal computed tomography (CT) scan revealed an inhomogeneous mass of 9.5 x 3.5 x 5.5 cm in diameter close to the appendix vermiformis and the sigmoid colon. Because of the clinical symptoms of an acute abdomen an explorative laparotomy was performed. Intraoperatively a pedunculated tumor beginning at the serosa of the sigmoid colon was found. The appendix was unremarkable. The macroscopic aspect as well as the backtable incision of the tumor was suspicious of an intraperitoneal liposarcoma. Rapid section and histopathologic examination revealed necrotic fat tissue without any malignancy. The patient was discharged from the hospital 7 days after the operation with normal laboratory parameters and without further complication. When epiploic appendagitis is evident as a big tumor mass in addition to clinical symptoms of an acute abdomen and elevated tumor markers, surgical exploration is mandatory.  相似文献   
79.
OBJECT: Vestibular schwannomas (VSs) with no or little extension into the internal auditory canal have been addressed as a clinical subentity carrying a poor prognosis regarding hearing preservation, which is attributed to the initially asymptomatic intracisternal growth pattern. The goal in this study was to assess hearing preservation in patients who underwent surgery for medial VSs. METHODS: A consecutive series of 31 cases in 30 patients with medial VSs (mean size 31 mm) who underwent surgery between 1997 and 2005 via a suboccipitolateral route was evaluated with respect to pre- and postoperative cochlear nerve function, extent of tumor removal, and radiological findings. Intraoperative monitoring of brainstem auditory evoked potentials was performed in all patients with hearing. Patients were reevaluated at a mean of 30 months following surgery. RESULTS: Preoperative hearing function revealed American Academy of Otolaryngology-Head and Neck Surgery Foundation Classes A and B in 7 patients each, Class C in 4, and D in 9. Four patients presented with deafness. Hearing preservation was achieved in 10 patients (Classes A-C in 2 patients each, and Class D in 4 patients). Tumor removal was complete in all patients with hearing preservation, except for 2 patients with neurofibromatosis. In 4 patients a planned subtotal excision was performed due to the individual's age or underlying disease. In 1 patient a recurrent tumor was completely removed 3 years after the initial procedure. CONCLUSIONS: The cochlear nerve in medial VSs requires special attention due to the atypical intracisternal growth pattern. Even in large tumors, hearing could be preserved in 37% of cases, since the cochlear nerve in medial schwannomas may not exhibit the adherence to the tumor capsule seen in tumors with comparable size involving the internal auditory canal.  相似文献   
80.
BACKGROUND: Accumulation of advanced glycation end products, that is, N(epsilon)-carboxymethyllysine (CML), induces oxidative stress and inflammation, and is present in chronic renal failure. Proximal tubular cells (PTCs) take up advanced glycation end products-bound proteins by apical megalin-receptors and degrade them. We hypothesized that renal transplant dysfunction affects renal CML homeostasis. Therefore, tubular and glomerular deposition of CML was investigated in a rat transplantation model, and in human allograft biopsies. METHODS: Fisher 344 kidneys were orthotopically transplanted into Lewis recipients. Recipients were treated with placebo, angiotensin II type 1 receptor blocker (candsartan 5 mg/kg/day), or calcium channel blocker (lacidipine 1 mg/kg/day) more than 28 weeks posttransplantation. Grafts were harvested at 12, 20, and 28 weeks posttransplantation. Sixty-two renal transplant patients underwent graft biopsy because of creatinine increase. Biopsies were graded according to interstitial fibrosis and tubular atrophy. N(epsilon)-carboxymethyllysine and megalin were semiquantitatively investigated in rats and humans using immunohistochemistry. RESULTS: In Fisher grafts, the development of transplant dysfunction was associated with a longitudinal increase in CML deposition in PTCs (week 12: 1.0+/-0.0, week 20: 1.5+/-0.3, week 28: 2.1+/-0.2, P<0.05). No glomerular deposition was present. In human graft biopsies, tubular CML deposition was negatively, and glomerular CML deposition was positively associated with transplant dysfunction (r=-0.29 and r=0.34; P<0.05). Megalin was reduced at advanced grades. CONCLUSION: N(epsilon)-carboxymethyllysine deposition increased in rat PTCs with mild transplant dysfunction. In humans, tubular CML deposition decreased in parallel with the reduction of its cellular uptake mechanism (megalin). Furthermore, glomerular deposition could play a pathophysiological role in chronic allograft injury.  相似文献   
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