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Journal of Thrombosis and Thrombolysis - The prognosis of pulmonary cement embolism found incidentally on chest radiography after vertebroplasty has been rarely investigated. This study was...  相似文献   
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Background and purpose

The current definition of atypical femoral fractures (AFFs) associated with bisphosphonate use includes only de novo fractures. However, in recent years reports of bisphosphonate-associated periprosthetic fractures involving stemmed arthroplasty implants have emerged. In a case series of peri-implant fractures in femurs with plate/screw constructs, we aimed to assess similarities with classical AFFs and how their location may have implications for the pathogenesis and management of AFFs.

Patients and methods

We retrospectively identified 10 patients with 11 peri-implant fractures.

Results

The patients were ambulant women, mean age 80 (70–92) years. Mean duration of bisphosphonate use was 5 (1–10) years. The peri-implant fractures were sustained an average of 4 years (6 months to 9 years) from the time of index surgery. They were all associated with low-energy mechanisms. 8 fractures occurred near the tip of a plate, while 3 traversed the penultimate screwhole of a plate. The peri-implant fractures showed clinical and radiological features of atypicality such as lateral cortical thickening, simple fracture pattern, and lack of comminution. The patients underwent revision surgery, with bone grafting used in all but 1 case. Radiological union was evident after 2–4 months.

Interpretation

Atypical peri-implant fractures of the femur associated with bisphosphonate use may be a new entity. Stress lesions and atypical fractures may tend to develop over stress risers along the operated femur. This finding has implications for the pathogenesis and clinical management of AFFs.Bisphosphonates form the cornerstone of antiresorptive therapy in the management of post-menopausal osteoporosis. They are used in the treatment of malignant and osteoclast-mediated metabolic bone disease. Their use in patients who have undergone total joint arthroplasty of the lower limb is associated with higher periprosthetic bone mineral density and longer implant survival (Bhandari et al. 2005). Bisphosphonates exert their therapeutic effect by reducing bone turnover and increasing overall mineralization. This translates to increased bone mineral density and bone strength, corresponding clinically to reduced risk of vertebral and non-vertebral fragility fractures (Black et al. 1996).In recent years, several published reports have described atypical femoral fractures (AFFs) of the proximal femoral diaphysis and subtrochanteric region, in association with bisphosphonate use (Goh et al. 2007, Neviaser et al. 2008, Isaacs et al. 2010). Bisphosphonates are associated with a higher age-adjusted relative risk of AFF in women than in men, which is higher in alendronate users than in risedronate users (Schilcher et al. 2015). Bisphosphonates may cause changes in bone matrix composition and bone mechanical properties, increasing the propensity for accumulation of microdamage. Impaired target remodeling would contribute to the progression of macrocracks. High interfragmentary strain from physiological loads at a thin fracture line may be a mechanical factor in lack of bone healing (Aspenberg et al. 2010).Periprosthetic/peri-implant fractures are currently excluded from the definition of AFFs. We suggest that peri-implant fractures of the femur with features of atypicality may be linked to bisphosphonate use and that they should be recognized as a clinical entity.  相似文献   
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LI is a subset of the heterotaxy syndrome and a rare birth defect that involves the heart and other organs. It can be combined with extracardiac abnormalities, especially BA. CHD can be associated with LI in up to 15% of cases, although it is rare in BA. Pediatric LT for a child with ESLD due to BA combined with LI and CHD is a challenging issue for a transplant surgeon. Herein, we report a successful split LT on a three‐yr‐old boy with LI who survived after a Fontan procedure due to single ventricle, but who suffered from HPS associated with BA.  相似文献   
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The aim of this study was to elucidate whether the thickness of the upper eyelid skin is affected by aging. The upper eyelid skins of 61 Korean women were subject to the study. Fusiform pieces of the skin, 3-mm wide, were obtained at the midpupillary line, 7 mm above the eyelashes, during blepharoplasty. The specimens were stained with hematoxylin and eosin. Thickness of the skin was measured by a micrometer under a microscope. It was substantially the same in all of the age groups. The thickness varied from 818 +/- 85 microm in subjects 60 years or older to 884 +/- 112 microm in subjects between 21-and 30-years old; the mean was 860 +/- 305 microm. Thickness of the epidermis varied from 46 +/- 6 microm in subjects between 41- and 50-years old to 52 +/- 10 microm in subjects between 31- and 40-years old; the mean was 49 +/- 9 microm. There were no significant differences among the age groups (P = 0.440). Thickness of the dermis varied from 771 +/- 78 microm in subjects older than 61 years to 834 +/- 112 microm in subjects between 21-and 30-years old; the mean was 811 +/- 117 microm. There were no significant differences between the age groups (P = 0.553). It is noticeable that upper eyelid skin thickness is not affected remarkably by aging.  相似文献   
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Despite improvements in outcomes for kidney transplant recipients in the past decade, graft failure continues to impose substantial burden on patients. However, the population‐wide economic burden of graft failure has not been quantified. This study aims to fill that gap by comparing outcomes from a simulation model of kidney transplant patients in which patients are at risk for graft failure with an alternative simulation in which the risk of graft failure is assumed to be zero. Transitions through the model were estimated using Scientific Registry of Transplant Recipients data from 1987 to 2017. We estimated lifetime costs, overall survival, and quality‐adjusted life‐years (QALYs) for both scenarios and calculated the difference between them to obtain the burden of graft failure. We find that for the average patient, graft failure will impose additional medical costs of $78 079 (95% confidence interval [CI] $41 074, $112 409) and a loss of 1.66 QALYs (95% CI 1.15, 2.18). Given 17 644 kidney transplants in 2017, the total incremental lifetime medical costs associated with graft failure is $1.38B (95% CI $725M, $1.98B) and the total QALY loss is 29 289 (95% CI 20 291, 38 464). Efforts to reduce the incidence of graft failure or to mitigate its impact are urgently needed.  相似文献   
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