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71.
72.
Palm H Jacobsen S Sonne-Holm S Gebuhr P;Hip Fracture Study Group 《The Journal of bone and joint surgery. American volume》2007,89(3):470-475
BACKGROUND: Reoperations after intertrochanteric fractures are often necessitated by fracture displacement following mobilization of the patient. The biomechanical complexity of the fracture, the position of the implant, and the patient's characteristics are known to influence postoperative outcome. We investigated the importance of an intact lateral femoral wall as a factor in postoperative fracture displacement after fixation with a sliding compression hip screw. METHODS: Two hundred and fourteen consecutive patients with an intertrochanteric fracture were treated with a 135 degrees sliding compression hip screw with a four-hole side-plate between 2002 and 2004. The fractures were classified on preoperative radiographs according to the AO/OTA classification system. The status of the greater and lesser trochanters, the integrity of the lateral femoral wall, and the position of the implant were assessed postoperatively. Reoperations due to technical failure were recorded for six months postoperatively. RESULTS: Only 3% (five) of 168 patients with an intact lateral femoral wall postoperatively underwent a reoperation within six months, whereas 22% (ten) of forty-six patients with a fractured lateral femoral wall were operated on again (p < 0.001). Multivariate logistic regression analyses combining demographic and biomechanical parameters showed a compromised lateral femoral wall to be a significant predictor of a reoperation (p = 0.010). Seventy-four percent (thirty-four) of the forty-six fractures of the lateral femoral wall occurred during the operative procedure itself. A fracture of the lateral femoral wall occurred in only 3% (three) of the 103 patients with an AO/OTA type-31-A1.1, A1.2, A1.3, or A2.1 intertrochanteric fracture compared with 31% (thirty-one) of the ninety-nine with an AO/OTA type 31-A2.2 or A2.3 fracture (p < 0.001). CONCLUSIONS: A postoperative fracture of the lateral femoral wall was found to be the main predictor for a reoperation after an intertrochanteric fracture. Consequently, we concluded that patients with preoperative or intraoperative fracture of the lateral femoral wall are not treated adequately with a sliding compression hip-screw device, and intertrochanteric fractures should therefore be classified according to the integrity of the lateral femoral wall, especially in randomized trials comparing fracture implants. 相似文献
73.
Ashwin A Kallianpur Rajinder Parshad Maya Dehran Priya Hazrah 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):229-234
BACKGROUND AND OBJECTIVES: Feasibility of ambulatory laparoscopic inguinal hernia repair in developing countries is not known due to lack of dedicated outpatient centers. This study prospectively evaluated the feasibility of outpatient discharge after laparoscopic total extraperitoneal inguinal hernia repair done in combination with in-hospital services and its impact on quality of life. METHODS: Forty patients were studied who had uncomplicated inguinal hernias and fulfilled the selection criteria. Quality of life was evaluated by using the SF-12 questionnaire. RESULTS: Ninety percent of patients could be discharged as outpatients. Four patients required admission. No major complications or readmissions occurred. Physical components of quality of life deteriorated in the immediate postoperative period but improved to above preoperative levels within one month. A transient deterioration in subgroups of the mental health component was observed, which recovered to normal in less than a week. There was no significant alteration in the emotional component. There has been no recurrence at a median follow-up of 25 months. CONCLUSION: It was feasible to safely perform outpatient TEP in combination with routine in-hospital services without increasing complications or causing any adverse impact on quality of life. This was possible subject to adherence to proper selection and discharge criteria. 相似文献
74.
Anti-LFA-1 improves pig islet xenograft function in diabetic mice when long-term acceptance is induced by CTLA4Ig/anti-CD40L 总被引:1,自引:0,他引:1
Kumagai-Braesch M Ekberg H Wang F Osterholm C Ehrnfelt C Sharma A Lindeborg E Holgersson J Corbascio M 《Transplantation》2007,83(9):1259-1267
BACKGROUND: It has been previously demonstrated that addition of anti-LFA-1 to a combination of CTLA4Ig and anti-CD40L induces the permanent acceptance of dopaminergic fetal pig xenografts when transplanted into the brain of wild-type mice. The purpose of this study was to test whether this costimulation blockade also can induce acceptance of adult pig islets transplanted to C57BL/6 mice with streptozotocin-induced diabetes. METHODS: Recipients were treated with CTLA4Ig/anti-CD40L+/-anti-LFA-1 or isotype control antibodies during the first week after transplantation. Half of the costimulation blockade-treated recipients had their grafts removed after 8 weeks. The other half was observed up to 5 months. RESULTS: Recipients treated with CTLA4Ig/anti-CD40L/anti-LFA-1 had significantly lower blood glucose and gained more weight than CTLA4Ig/anti-CD40L-treated recipients. CTLA4Ig/anti-CD40L-treated recipients exhibited unstable blood glucose. IPGTT of these recipients revealed a slow recovery to normal blood glucose levels at week 4. In comparison, CTLA4Ig/anti-CD40L/anti-LFA-1 treated recipients exhibited a significantly superior glucose clearance. CTLA4Ig/anti-CD40L+/-anti-LFA-1 treated recipients did not produce anti-pig IgG, whereas control antibody-treated mice did. CD4+ T cells from costimulation blockade-treated recipients proliferated less than CD4+ T cells from control antibody-treated mice when co-cultured with syngeneic antigen presenting cells loaded with pig islet antigens. CONCLUSIONS: CTLA4Ig/anti-CD40L/anti-LFA-1-treated recipients had superior islet function compared with CTLA4Ig/anti-CD40L-treated recipients. However, both costimulation blockade regimens led to islet graft acceptance up to 5 months after a 1-week treatment. 相似文献
75.
Henrik Dimke Matthew A. Sparks Benjamin R. Thomson Sebastian Frische Thomas M. Coffman Susan E. Quaggin 《Journal of the American Society of Nephrology : JASN》2015,26(5):1027-1038
Vascular endothelial growth factor A (VEGFA) production by podocytes is critical for glomerular endothelial health. VEGFA is also expressed in tubular epithelial cells in kidney; however, its physiologic role in the tubule has not been established. Using targeted transgenic mouse models, we found that Vegfa is expressed by specific epithelial cells along the nephron, whereas expression of its receptor (Kdr/Vegfr2) is largely restricted to adjacent peritubular capillaries. Embryonic deletion of tubular Vegfa did not affect systemic Vegfa levels, whereas renal Vegfa abundance was markedly decreased. Excision of Vegfa from renal tubules resulted in the formation of a smaller kidney, with a striking reduction in the density of peritubular capillaries. Consequently, elimination of tubular Vegfa caused pronounced polycythemia because of increased renal erythropoietin (Epo) production. Reducing hematocrit to normal levels in tubular Vegfa–deficient mice resulted in a markedly augmented renal Epo production, comparable with that observed in anemic wild-type mice. Here, we show that tubulovascular cross-talk by Vegfa is essential for maintenance of peritubular capillary networks in kidney. Disruption of this communication leads to increased renal Epo production and resulting polycythemia, presumably to counterbalance microvascular losses. 相似文献
76.
Olle Muren Ehsan Akbarian Mats Salemyr Henrik Bodén Thomas Eisler André Stark Olof Sk?ldenberg 《Acta orthopaedica》2015,86(5):569-574
Background and purpose
We have previously shown that during the first 2 years after total hip arthroplasty (THA), periprosthetic bone resorption can be prevented by 6 months of risedronate therapy. This follow-up study investigated this effect at 4 years.Patients and methods
A single-center, double-blind, randomized placebo-controlled trial was carried out from 2006 to 2010 in 73 patients with osteoarthritis of the hip who were scheduled to undergo THA. The patients were randomly assigned to receive either 35 mg risedronate or placebo orally, once a week, for 6 months postoperatively. The primary outcome was the percentage change in bone mineral density (BMD) in Gruen zones 1 and 7 in the proximal part of the femur at follow-up. Secondary outcomes included migration of the femoral stem and clinical outcome scores.Results
61 of the 73 patients participated in this 4-year (3.9- to 4.1-year) follow-up study. BMD was similar in the risedronate group (n = 30) and the placebo group (n = 31). The mean difference was −1.8% in zone 1 and 0.5% in zone 7. Migration of the femoral stem, the clinical outcome, and the frequency of adverse events were similar in the 2 groups.Interpretation
Although risedronate prevents periprosthetic bone loss postoperatively, a decrease in periprosthetic BMD accelerates when therapy is discontinued, and no effect is seen at 4 years. We do not recommend the use of risedronate following THA for osteoarthritis of the hip.Adaptive bone remodeling around the femoral stem following total hip arthroplasty (THA) results in regional loss of bone mass, especially in proximal parts of the femur—most of which takes place within the first postoperative year (Bodén et al. 2006, Sköldenberg et al. 2006). Periprosthetic bone loss may predispose to periprosthetic fracture, aseptic loosening, and difficulties at revision surgery (Lindahl 2007, Streit et al. 2011, Sköldenberg et al. 2014).The bisphosphonate (BP) risedronate has been used successfully to prevent osteoporotic fractures, mainly in the hip and vertebrae, by inhibiting osteoclast activity (McClung et al. 2001). In recent years, the possible use of BPs to prevent or ameliorate periprosthetic adaptive bone resorption, osteolysis, and implant migration has been investigated thoroughly in animal models and humans. The short-term results of several studies showing the effects of postoperative BP treatment in reducing periprosthetic bone loss up to a year after the arthroplasty have already been published (Venesmaa et al. 2001, Wilkinson et al. 2001, Hennigs et al. 2002, Wilkinson et al. 2005, Arabmotlagh et al. 2006).We have previously found that risedronate given once a week for 6 months after THA reduces periprosthetic bone resorption around an uncemented femoral stem in the first and second postoperative year (Sköldenberg et al. 2011). We now report the 4-year outcome in the same cohort. 相似文献77.
78.
79.
Christian Linden Henrik G Ahlborg Jack Besjakov Per Gardsell Magnus K Karlsson 《Journal of bone and mineral research》2006,21(6):829-835
This 2-year prospective controlled exercise intervention trial in 99 girls at Tanner stage 1, evaluating a school curriculum-based training program on a population-based level, showed that the annual gain in BMC, aBMD, and bone size was greater in the intervention group than in the controls. INTRODUCTION: Most exercise intervention studies in children, evaluating the accrual of BMD, include volunteers and use specifically designed osteogenic exercise programs. The aim of this study was to evaluate a 2-year general school-based exercise intervention program in a population-based cohort of girls at Tanner stage 1. MATERIALS AND METHODS: Forty-nine girls 7-9 years of age in grades 1 and 2 in one school were included in a school curriculum-based exercise intervention program of general physical activity for 40 minutes per school day (200 minutes/week). Fifty healthy age-matched girls in three neighboring schools, assigned to the general Swedish school curriculum of physical activity (60 minutes/week), served as controls. All girls were premenarchal, remaining in Tanner stage 1 during the study. BMC (g) and areal BMD (aBMD; g/cm2) were measured with DXA of the total body (TB), the lumbar spine (L2-L4 vertebrae), the third lumbar vertebra (L3), the femoral neck (FN), and the leg. Volumetric BMD (vBMD; g/cm3) and bone size were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. Height and weight were also registered. Baseline measurements were performed before the intervention was initiated. Follow-up was done after 2 years. RESULTS: No differences between the groups were found at baseline in age, anthropometrics, or bone parameters. The annual gain in BMC was greater in the intervention group than in the controls: L2-L4, mean 3.8 percentage points (p = 0.007); L3 vertebra, mean 7.2 percentage points (p < 0.001); legs, mean 3.0 percentage points (p = 0.07). The intervention group had a greater annual gain in aBMD: total body, mean 0.6 percentage points (p = 0.006), L2-L4, mean 1.2 percentage points (p = 0.02), L3 vertebra, mean 1.6 percentage points (p = 0.006); legs, mean 1.2 percentage points (p = 0.007). There was also a greater mean annual gain in bone size in the L3 vertebra (mean 1.8 percentage points; p < 0.001) and in the FN (mean 0.3 percentage points; p = 0.02). CONCLUSIONS: A general school-based exercise program for 2 years for 7- to 9-year-old girls (baseline) enhances the accrual of BMC and BMD and increases bone size. 相似文献
80.
Abrahamsen B Jørgensen HL Nielsen TL Andersen M Haug E Schwarz P Hagen C Brixen K 《BONE》2006,38(2):215-219
The MTHFR c.677C>T polymorphism has been shown to have significant effects on skeletal health in middle-aged to elderly women and men. Despite an accumulating amount of data on MTHFR genetics and the association between homocysteine levels and fracture, it remains unknown if MTHFR c.677C>T genotype affects bone mineral accretion in youth or bone loss in adulthood. The purpose of this cross-sectional study was to examine the effects of this common allelic polymorphism on peak bone mass and bone turnover. We performed MTHFR genotyping in 780 healthy Danish men, aged 20 to 29 years, participating in the Odense Androgen Study. BMD at the spine, hip and whole-body was measured using a Hologic QDR-4500 densitometer. Genotype frequencies were compatible with Hardy-Weinberg equilibrium. Spine BMD was significantly associated with genotype, with a decrease in BMD of 0.20 SD for each copy of the T-allele. Effects were independent of age, BMI, smoking and serum levels of vitamin D and IGF-I. Associations with BMD of the hip and whole body were short of statistical significance. MTHFR genotype showed no association with the bone turnover markers 1-CTP, bone specific alkaline phosphatase or osteocalcin. In conclusion, significant skeletal effects of this common polymorphism were present at the lumbar spine in men at the age of 25 years. 相似文献