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81.
We report the outcome in 32 patients operated on for advanced periacetabular metastatic destruction, where all but 2 had Harrington class III destruction. The patients were operated on using the Harrington reconstruction technique, where threaded pins and cement and a total hip replacement are used to reconstruct the acetabulum and ilium. The median survival was 11 (0-106+) months. 13 patients lived for a year or more. At follow-up after 1 year, 10 of the 13 were free of pain at rest and weight-bearing, 6 were walking with and 7 without support, and 11 lived outside a health care facility. 2 patients died within 2 weeks of surgery, both of excessive peroperative bleeding. 2 patients had dislocations, 1 developed a deep infection, and 2 patients deep vein thrombosis. There were no complications caused by erroneous pin placement or intraoperative thromboembolic incidents. There were no mechanical failures, or radiographic signs of loosening, of the pelvic components. The Harrington reconstruction technique is an effective and long-lasting method to relieve pain and restore function in patients with advanced periacetabular metastatic destruction.  相似文献   
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Implant osseointegration can currently only be assessed reliably post mortem. A novel method that relies on the principle of acoustic sound analysis was developed to enable examination of the longitudinal progress of osseointegration. The method is based on a magnetic sphere inside a hollow cylinder of the implant. By excitation using an external magnetic field, collision of the sphere inside the implant produces a sound signal. Custom‐made titanium implants equipped thusly were inserted in each lateral femoral epicondyle of 20 New Zealand White Rabbits. Two groups were investigated: Uncoated, machined surface versus antiadhesive surface; and calcium phosphate‐coated surface versus antiadhesive surface. The sound analysis was performed postoperatively and weekly. After 4 weeks, the animals were euthanized, and the axial pull‐out strengths of the implants were determined. A significant increase in the central frequency was observed for the loose implants (mean pull‐out strength 21.1 ± 16.9 N), up to 6.4 kHz over 4 weeks. In comparison, the central frequency of the osseointegrated implants (105.2 ± 25.3 N) dropped to its initial value. The presented method shows potential for monitoring the osseointegration of different implant surfaces and could considerably reduce the number of animals needed for experiments. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:606–612, 2014.  相似文献   
85.
INTRODUCTION: The European Lacidipine Study on Atherosclerosis (ELSA) has been planned to investigate the effect of reduction in office and ambulatory blood pressure by lacidipine versus atenolol on carotid artery wall thickness in mild to moderate essential hypertensive patients with no metabolic abnormalities. One prespecified sub-study of ELSA focused on measurements of arterial distensibility in the carotid as well as in the radial artery to determine the relationship of functional arterial properties with office versus ambulatory blood pressure (BP) values as well as the correspondence between functional and structural arterial alterations. METHODS: The sub-study was conducted on 124 patients recruited in four centres (Monza-Milan, Paris, Grenoble and Glasgow). BP was measured both by a mercury sphygmomanometer and by 24-h ambulatory monitoring. Common carotid artery wall thickness was measured by certified sonographers as described in the main study. Common carotid and radial artery distensibility were obtained by echotracking techniques, which allowed to relate changes in arterial diameter with systo-diastolic BP changes. RESULTS: Carotid artery wall distensibility showed (1) a negative correlation with office and more so 24-h average systolic BP (r = -0.45 and -0.58, P < 0.008 and 0.001) but not with office or 24-h diastolic BP) and (2) a negative correlation with the corresponding wall thickness (r = -0.47, P < 0.005). In contrast, at the radial artery level distensibility and thickness showed no correlation with each other and with BP. Carotid (but not radial) artery distensibility also correlated with ambulatory systolic BP variability but the correlation was lost after adjustment for age and mean BP values. CONCLUSION: These data suggest that stiffening of large elastic artery is reflected more by ambulatory than office BP elevations, systolic BP being much more important than diastolic. Alterations of large elastic arteries function is related to structural wall changes. Functional and structural properties of middle-size muscle arteries are independent of BP.  相似文献   
86.
OBJECTIVE: To investigate the potential of transgene-activated periosteal cells for permanently resurfacing large partial-thickness cartilage defects. METHODS: In miniature pigs, autologous periosteal cells stimulated ex vivo by bone morphogenetic protein 2 gene transfer, using liposomes or a combination of adeno-associated virus (AAV) and adenovirus (Ad) vectors, were applied on a bioresorbable scaffold to chondral lesions comprising the entire medial half of the patella. The resulting repair tissue was assessed, 6 and 26 weeks after transplantation, by histochemical and immunohistochemical methods. The biomechanical properties of the repair tissue were characterized by nanoindentation measurements. Implants of unstimulated cells and untreated lesions served as controls. RESULTS: All grafts showed satisfactory integration into the preexisting cartilage. Six weeks after transplantation, AAV/Ad-stimulated periosteal cells had adopted a chondrocyte-like phenotype in all layers; the newly formed matrix was rich in proteoglycans and type II collagen, and its contact stiffness was close to that of healthy hyaline cartilage. Unstimulated periosteal cells and cells activated by liposomal gene transfer formed only fibrocartilaginous repair tissue with minor contact stiffness. However, within 6 months following transplantation, the AAV/Ad-stimulated cells in the superficial zone tended to dedifferentiate, as indicated by a switch from type II to type I collagen synthesis and reduced contact stiffness. In deeper zones, these cells retained their chondrocytic phenotype, coinciding with positive staining for type II collagen in the matrix. CONCLUSION: Large partial-thickness cartilage defects can be resurfaced efficiently with hyaline-like cartilage formed by transgene-activated periosteal cells. The long-term stability of the cartilage seems to depend on physicobiochemical factors that are active only in deeper zones of the cartilaginous tissue.  相似文献   
87.

Background

Different studies have shown that atrophy of paraspinal muscles arises after open dorsal lumbar fusion, and the reasons for this atrophy are still not yet fully clarified. This prospective study investigates the extent of atrophy of the lumbar paraspinal muscles after open lumbar interbody fusion, its possible causes, and their association with clinical outcome measures.

Methods

Thirty consecutive patients were prospectively included (13 male, 17 female, median age 60.5 years, range 33–80 years). Mono or bisegmental, posterior lumbar interbody fusion and instrumentation was performed applying a conventional, open lumbar midline approach. Clinical outcome was assessed by the Short Form (36) Health Survey (SF-36) questionnaire and visual analogue scale. Needle electromyography of paraspinal muscles was performed preoperatively, at 6 and 12 months. Serum values of creatine kinase, lactate dehydrogenase and myoglobin were determined preoperatively, at day 2 after surgery and at discharge. Paraspinal muscle volume was determined by volumetric analysis of thin-slice computed tomography scans preoperatively and 1 year after surgery.

Results

There was a significant increase of electromyographic denervation activity (p =0.024) and reduced recruitment of motor units (p?=?0.001) after 1 year. Laboratory studies showed a significant increase of CK (p?<?0.001) and myoglobin (p < 0.001) serum levels at day 2 after surgery. The paraspinal muscle volume decreased from 67.8 to 60.4 % (p < 0.001) after 1 year. Correlation analyses revealed a significant negative correlation between denervation and muscle volume (K = -0.219, p = 0.002). Paraspinal muscle volume is significantly correlated with physical outcome (K = 0.169, p = 0.020), mental outcome (K = 0.214, p = 0.003), and pain (K = 0.382, p < 0.001) after 1 year.

Conclusions

Atrophy of paraspinal muscles after open, posterior lumbar interbody fusion seems to be associated with denervation, as well as direct muscle trauma during surgery. While muscle atrophy is also correlated with a worse clinical outcome, it seems to be a determining factor for successful lumbar spine surgery.  相似文献   
88.

Background

Autologous bone flap reinsertion follows as a second surgical intervention after decompressive craniectomy in patients with malignant middle cerebral artery (MCA) infarction. In addition to surgery-related short-term complications, aseptic resorption of the reimplanted bone flap is a possible long-term problem which has not yet been sufficiently elucidated in these patients.

Methods

A total of 109 patients who had undergone decompressive hemicraniectomy for malignant MCA infarction in our institution between September 1994 and December 2011 were included in the study. Clinical and radiological findings were retrieved retrospectively. Aseptic bone necrosis was classified into two categories based on computer tomographic features.

Results

A total of 76 patients received their own cryoconserved bone flap (mean age 54.34 ± 10.73 years; 49 males). The overall short-term complication rate was 9.2 %. Bone flap necrosis occurred in 26 patients (22.8 %) with 7 flaps showing signs of surgically relevant type II necrosis after a median time of 14 months (interquartile range [IQR] 4–22).

Conclusions

There is a noticeable complication rate in patients undergoing bone flap reinsertion after hemicraniectomy due to malignant MCA infarction. Aseptic bone necrosis represents a significant complication during long-term follow-up. The pathophysiological mechanisms remain unclear and more efforts should be undertaken to understand and possibly prevent this complication in these patients.  相似文献   
89.

Introduction

Bortezomib is a proteasome inhibitor that has shown important clinical efficacy either as a single agent or in combination in patients with multiple myeloma (MM). In the present protocol, bortezomib was combined with bendamustine and prednisone, in order to assess the efficacy and safety of this combination therapy in patients with newly diagnosed/untreated MM.

Methods

Between June 2006 and October 2013, 49 patients with newly diagnosed/untreated MM were treated with bendamustine 60 mg/m2 on days 1 and 2, bortezomib 1.3 mg/m2 on days 1, 4, 8 and 11, and prednisone 100 mg on days 1, 2, 4, 8 and 11 bendamustine, prednisone and bortezomib (BPV) once every 21 days. Patients were divided into three groups: group A (n = 19) consisted of patients with normal renal function or mild dysfunction (eGFR ≥60 ml/min), group B (n = 15) patients with moderate or severe renal dysfunction (eGFR 15–59 ml/min) and group C (n = 15) patients with renal failure/dialysis (eGFR <15 ml/min).

Results

A median number of two (range 1–5) BPV treatment cycles were given to the patients. The majority of the patients (n = 40, 82 %) responded after at least one cycle of BPV therapy with five stringent complete responses (CRs), nine near complete responses, 12 very good partial responses and 14 partial responses. Five patients had MR, three stable and one progressive disease. After a median observation time of 13 months, progression-free survival (PFS) and overall survival (OS) at 12 months were 92 and 94 %, respectively, for patients with normal renal function or mild renal dysfunction (group A) and 83 and 93 %, respectively, for patients with moderate or severe renal dysfunction (group B). Outcome for these patients was slightly better but not statistically significantly better than that for patients with renal failure/dialysis (group C), who had a PFS, and OS of 66 % (p = 0.08) and 73 % (p = 0.05), respectively.

Summary

These results indicate that this BPV combination is feasible, effective and well tolerated in patients with newly diagnosed MM and normal or impaired renal function.  相似文献   
90.
Visual neglect results from dysfunction within the spatial attention network. The structural connectivity in undamaged brain tissue in neglect has barely been investigated until now. In the present study, we explored the microstructural white matter characteristics of the contralesional hemisphere in relation to neglect severity and recovery in acute stroke patients. We compared age‐matched healthy subjects and three groups of acute stroke patients (9 ± 0.5 days after stroke): (i) patients with nonrecovered neglect (n = 12); (ii) patients with rapid recovery from initial neglect (within the first week post‐stroke, n = 7), (iii) stroke patients without neglect (n = 17). We analyzed the differences between groups in grey and white matter density and fractional anisotropy (FA) and used fiber tracking to identify the affected fibers. Patients with nonrecovered neglect differed from those with rapid recovery by FA‐reduction in the left inferior parietal lobe. Fibers passing through this region connect the left‐hemispheric analogues of the ventral attention system. Compared with healthy subjects, neglect patients with persisting neglect had FA‐reduction in the left superior parietal lobe, optic radiation, and left corpus callosum/cingulum. Fibers passing through these regions connect centers of the left dorsal attention system. FA‐reduction in the identified regions correlated with neglect severity. The study shows for the first time white matter changes within the spatial attention system remote from the lesion and correlating with the extent and persistence of neglect. The data support the concept of neglect as disintegration within the whole attention system and illustrate the dynamics of structural‐functional correlates in acute stroke. Hum Brain Mapp 35:4678–4692, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
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