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Hugo C. van der Veen Hans-Peter W. van Jonbergen Rudolf W. Poolman Sjoerd K. Bulstra Jos J. A. M. van Raay 《International orthopaedics》2013,37(1):9-14
Joint arthroplasty registries show an increased rate of aseptic loosening in uncemented acetabular components as compared to cemented acetabular components. Since loosening is associated with particulate wear debris, we postulated that uncemented acetabular components demonstrate a higher polyethylene wear rate than cemented acetabular components in total hip arthroplasty. We performed a systematic review of the peer-reviewed literature, comparing the wear rate in uncemented and cemented acetabular components in total hip arthroplasty. Studies were identified using MEDLINE (PubMed), EMBASE and the Cochrane Central Register of Controlled Trials. Study quality was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The search resulted in 425 papers. After excluding duplicates and selection based on title and abstracts, nine studies were found eligible for further analysis: two randomised controlled trials, and seven observational studies. One randomised controlled trial found a higher polyethylene wear rate in uncemented acetabular components, while the other found no differences. Three out of seven observational studies showed a higher polyethylene wear in uncemented acetabular component fixation; the other four studies did not show any differences in wear rates. The available evidence suggests that a higher annual wear rate may be encountered in uncemented acetabular components as compared to cemented components. 相似文献
74.
Felix Nickel Hannes G. Kenngott Jochen Neuhaus Christof M. Sommer Tobias Gehrig Armin Kolb Matthias Gondan Boris A. Radeleff Anja Schaible Hans-Peter Meinzer Carsten N. Gutt Beat-Peter Müller-Stich 《Surgical endoscopy》2013,27(10):3663-3670
Background
Navigation systems potentially facilitate minimally invasive esophagectomy and improve patient outcome by improving intraoperative orientation, position estimation of instruments, and identification of lymph nodes and resection margins. The authors’ self-developed navigation system is highly accurate in static environments. This study aimed to test the overall accuracy of the navigation system in a realistic operating room scenario and to identify the different sources of error altering accuracy.Methods
To simulate a realistic environment, a porcine model (n = 5) was used with endoscopic clips in the esophagus as navigation targets. Computed tomography imaging was followed by image segmentation and target definition with the medical imaging interaction toolkit software. Optical tracking was used for registration and localization of animals and navigation instruments. Intraoperatively, the instrument was displayed relative to segmented organs in real time. The target registration error (TRE) of the navigation system was defined as the distance between the target and the navigation instrument tip. The TRE was measured on skin targets with the animal in the 0° supine and 25° anti-Trendelenburg position and on the esophagus during laparoscopic transhiatal preparation.Results
On skin targets, the TRE was significantly higher in the 25° position, at 14.6 ± 2.7 mm, compared with the 0° position, at 3.2 ± 1.3 mm. The TRE on the esophagus was 11.2 ± 2.4 mm. The main source of error was soft tissue deformation caused by intraoperative positioning, pneumoperitoneum, surgical manipulation, and tissue dissection.Conclusion
The navigation system obtained acceptable accuracy with a minimally invasive transhiatal approach to the esophagus in a realistic experimental model. Thus the system has the potential to improve intraoperative orientation, identification of lymph nodes and adequate resection margins, and visualization of risk structures. Compensation methods for soft tissue deformation may lead to an even more accurate navigation system in the future. 相似文献75.
Claudia Schnabel Kimberly Jett Jan M. Friedman Isolde Frieling Hans-Peter Kruse Victor Mautner 《Joint, bone, spine : revue du rhumatisme》2013,80(3):315-319
ObjectivesWe have previously demonstrated reduced bone density and an increased incidence of 25-hydroxy vitamin D3 (25-OH D3) deficiency in adults with neurofibromatosis 1 (NF1) compared to healthy controls. Vitamin D3 is a cheap, safe, and effective supplement in the general population, but its value in NF1 patients has not been demonstrated. This study investigates the therapeutic potential of oral vitamin D3 on bone mineral density (BMD) in NF1 patients with vitamin D3 deficiency.MethodsWe measured serum 25-OH D3, parathyroid hormone, calcium, and bone alkaline phosphatase concentrations, urinary deoxypyridinoline concentrations, and BMD in 35 adults with NF1. Nineteen patients received vitamin D3 supplementation for 2 years, six patients received supplementation for 1 year and 10 patients received no supplementation. Supplementation was administered in a dose that maintained the serum 25-OH D3 level above 30 μg/l. BMD was measured again at 1 and 2 years, and biochemical assessments of bone metabolism were measured at least every half year during therapy.ResultsTreated subjects had significantly reduced loss of BMD, as measured by T score at the hip (p = 0.011) and lumbar spine (p = 0.022). The effect on hip BMD was apparent at 1 year in comparison to baseline (p = 0.02) and was greater at 2 years in comparison to measurements at 1 year (p = 0.02).ConclusionsVitamin D3 supplementation improves BMD in adult NF1 patients. Further studies are needed to elucidate the mechanisms responsible for reduced BMD in NF1 patients. 相似文献
76.
Clément M. L. Werner Stefan M. Zimmermann Carola C. Würgler-Hauri Joseph M. Lane Guido A. Wanner Hans-Peter Simmen 《HSS journal》2013,9(2):166-170
Background
Heterotopic ossification (HO) is a common complication following orthopedic and trauma surgery, which may have substantial negative effects on the postoperative outcome. Angiogenesis appears to play a critical role in heterotopic ossification. One of the involved signaling molecules is platelet-derived growth factor (PDGF) which may be inhibited by imatinib.Questions/Purposes
Our goal was to prevent HO by pharmacologically interfering with the molecular signaling pathways involved in the developmental process. We hypothesized that by administering a proven inhibitor of PDGF expression, heterotopic bone formation may be prevented.Methods
The effect of imatinib on HO formation was studied in a murine model which reliably produces islets of HO within the soft tissue following Achilles tenotomy. The control group underwent Achilles tenotomy only. The imatinib group received imatinib mesylate. After trial completion, the limbs were harvested and scanned by micro-CT. Heterotopic bone volume was then identified and quantified.Results
The mean volume of heterotopic bone formed in the control group was 0.976mm3 compared to 0.221 mm3 in the imatinib group. The volume of HO in the treatment group was reduced by 85% compared to the control group.Conclusions
The administration of imatinib was associated with a significantly reduced volume of HO. This may be due to the inhibitory effect of imatinib on the PDGF signaling pathway during development of HO.Clinical Relevance
The successful reduction of HO formation following imatinib administration has led to further insight concerning the pathogenesis of HO which in the future may lead to new clinical approaches towards the prevention of HO.Electronic supplementary material
The online version of this article (doi:10.1007/s11420-013-9335-y) contains supplementary material, which is available to authorized users. 相似文献77.
78.
Eva Wolf Markus Utech Peter Stehle Martin Büsing Hans-Peter Helfrich Birgit Stoffel-Wagner Sarah Egert Birgit Alteheld Raute Riege Annette Knapp Sabine Ellinger 《Obesity surgery》2016,26(8):1821-1829
Background
Osteomalacia and cardiometabolic disorders are favored in morbidly obese patients due to an inadequate vitamin D (VD) status. Former trials supplementing orally VD (20–50 μg/day) in crystalline form after sleeve gastrectomy (SG) could not stabilize serum 25-hydroxycholecalciferol levels at predefined concentrations (≥50 nmol/l). We hypothesized that VD in an oily suspension would increase its bioavailability resulting in normal serum VD levels minimizing markers of cardiometabolic risk.Methods
Morbidly obese patients (n?=?94, BMI 51.8?±?11.5 kg/m2) received orally 80 μg/day VD3 dissolved in oil or placebo (pure oil) in a randomized, double-blind, parallel-group study for 12 weeks after SG. 25-hydroxycholecalciferol, parathyroid hormone, albumin, alkaline phosphatase, phosphate, magnesium, calcium, creatinine, C-reactive protein, lipids, glucose, and glycated hemoglobin were determined in serum/plasma before surgery and after 4 and 12 weeks of supplementation. Intake of energy, fat, and VD were monitored using a 3-day food record.Results
Seventy-nine patients were included in statistical analysis. Preoperatively, 77.2 and 40.5 % presented 25-hydroxycholecalciferol levels <75 and <50 nmol/l, respectively. After 12 weeks of supplementation, significantly more patients in the VD group exhibited levels >50 nmol/l (92 %) and >75 nmol/l (68 %) compared to the placebo group (54 and 22 %, respectively). Parameters of mineral metabolism and cardiometabolic risk were not modulated by intervention.Conclusion
Supplementation of 80 μg/day VD3 by oil is an effective and safe measure to prevent VD deficiency and to treat a preexisting undersupply in patients after SG. Cardiometabolic risk factors were, however, not affected; probably, higher VD doses might be necessary.Clinical Trial Registration
This trial was registered retrospectively on November 14, 2014, at the German Clinical Trials Register as DRKS00007143.79.
Beesdo-Baum Katja Knappe Susanne Einsle Franziska Knothe Lisa Wieder Gesine Venz John Rummel-Kluge Christine Heinz Ines Koburger Nicole Schouler-Ocak Meryam Wilbertz Theresia Unger Hans-Peter Walter Ulrich Hein Joachim Hegerl Ulrich Lieb Roselind Pfennig Andrea Schmitt Jochen Hoyer Jürgen Wittchen Hans-Ulrich Bergmann Antje 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(1):52-64
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Hausärzte sind als Primärversorger für Patienten mit depressiven Störungen entscheidende Weichensteller... 相似文献
80.