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31.
Bjørg-Tilde S. Fevang Stein H. L. Lygre Glenn Bertelsen Arne Skredderstuen Leif I. Havelin Ove Furnes 《International orthopaedics》2013,37(1):59-66
Purpose
Functional results of reversed total prostheses (RTP) have—to a very limited degree—been compared with those of other shoulder prosthesis types. The aim of our study was to compare results of four different types of shoulder prostheses in terms of function, pain, and quality of life (QoL).Methods
Questionnaires were completed by 859 patients with shoulder prostheses registered in the Norwegian Arthroplasty Register. Patients with osteoarthritis (OA), rheumatoid arthritis (RA), or fracture sequela (FS) were included. Symptoms and function were assessed using the Oxford Shoulder Score (OSS, scale 0–48), and the EuroQoL-5D (EQ-5D) was used to assess QoL.Results
Best functional results were obtained using conventional total prostheses (TPs) and RTPs —mean OSS improvement 18 and 16 units, respectively, vs 11 with hemiprostheses (HPs). For patients with OA, TPs performed best; for those with RA and FS, RTPs performed best; and those with HPs had the worst results in all diagnostic groups. The greatest improvement in QoL was seen in patients with TPs and RTPs.Conclusions
Conventional TPs provide the best improvement in pain, function and QoL in OA patients; RTPs are superior in patients with RA and FS. 相似文献32.
Lars Engesæter Stein Atle Lie Birgitte Espehaug Ove Furnes Stein Emil Vollset Leif Ivar Havelin 《Acta orthopaedica》2013,84(6):644-651
We studied the effects of antibiotic prophylaxis, systemically and in bone cement, on the revision rate of cemented total hip arthroplasties (THAs) in data from the Norwegian Arthroplasty Register during the period 1987-2001. To have comparable groups, only THAs performed because of primary osteoarthritis, using cemented implants with documented good results, and high-viscosity cement were included. If systemic antibiotic prophylaxis had been given, only operations with cephalosporin or penicillin were selected. Cox-estimated survival relative revision risks (RR) are presented with adjustment for differences among groups in gender, age, cement brand, type of systemic antibiotic prophylaxis, type of prosthesis, type of operating room, and duration of the operation. Of 22,170 THAs studied, 696 THAs (3.1%) were revised, 440 (2.0%) for aseptic loosening and 102 (0.5%) for deep infection. We found the lowest risk of revision when the antibiotic prophylaxis was given both systemically and in the cement (15,676 THAs). Compared to this combined regime, patients who received antibiotic prophylaxis only systemically (5,960 THAs) had a 1.4 times higher revision rate with all reasons for revision as endpoint (p= 0.001), 1.3 times higher with aseptic loosening (p= 0.02) and 1.8 times higher with infection as the endpoint (p= 0.01). With the combined antibiotic regime, the results were better if antibiotics were given 4 times on the day of surgery (2,194 THAs), as compared to once (1,424 THAs) (p<0.001), twice (2,680 THAs) (p<0.001), or 3 times (5,522 THAs) (p= 0.02). Those who received systemic prophylaxis a single day 1, 2 or 3 times, as compared to 4 times, had a revision rate 1.8-3.5 times higher with all reasons for revision as endpoint, 1.5-3.1 times higher with aseptic loosening, and 2.7-6.8 times higher with infection. When we compared systemic prophylaxis 4 times in 1 day, no further improvement resulted in those given systemic prophylaxis for 2 days (1,928 THAs) or 3 days (717 THAs). In a subset of data including only the Charnley prosthesis, we obtained similar results. This observational study shows that the best results were recorded when antibiotic prophylaxis was given both systemically and in the bone cement, and if the systemic antibiotic was given 4 times on the day of surgery. 相似文献
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Mette Munk Lauridsen Jesper Frøjk Ove B Schaffalitzky de Muckadell Hendrik Vilstrup 《Metabolic brain disease》2014,29(3):655-660
The continuous reaction times (CRT) method describes arousal functions. Reaction time instability in a patient with liver disease indicates covert hepatic encephalopathy (cHE). The effects of sleep deprivation are unknown although cirrhosis patients frequently suffer from sleep disorders. The aim of this study was to determine if sleep deprivation influences the CRT test. Eighteen cirrhosis patients and 27 healthy persons were tested when rested and after one night’s sleep deprivation. The patients filled out validated sleep quality questionnaires. Seven patients (38 %) had unstable reaction times (a CRTindex?1.9) compatible with cHE. In these patients, the wakefulness improved or normalized their reaction speed and CRTindex (p?=?0.01). There was no change in the other patients’ reaction speed or stability. Seven patients (38 %) reported poor sleep that was not related to their CRT tests before or after the sleep deprivation. In the healthy participants, the sleep deprivation slowed their reaction times by 11 % (p?0.0001) and in 7 persons (25 %) destabilized them. The acute sleep deprivation normalized or improved the reaction time stability of the patients with a CRTindex below 1.9 and had no effect in the patients with a CRTindex above 1.9. There was no relation between reported sleep quality and reaction time results. Thus, in cirrhosis patients, sleep disturbances do not lead to ‘falsely’ slowed and unstable reaction times. In contrast, the acute sleep deprivation slowed and destabilized the reaction times of the healthy participants. This may have negative consequences for decision-making. 相似文献
37.
38.
Eva Dybvik Ove Furnes Sophie D. Foss? Clement Trovik Stein Atle Lie 《Acta orthopaedica》2014,85(6):652-656
Background and purpose —
Long-term survivors of cancer can develop adverse effects of the treatment. 60% of cancer patients survive for at least 5 years after diagnosis. Pelvic irradiation can cause bone damage in these long-term survivors, with increased risk of fracture and degeneration of the hip.Patients and methods —
Analyses were based on linkage between the Cancer Registry of Norway (CRN) and the Norwegian Arthroplasty Register (NAR). All women who had been exposed to radiation for curative radiotherapy of gynecological cancer (40–60 Gy for at least 28 days) were identified in the CRN. Radiotherapy had been given between 1998 and 2006 and only patients who were irradiated within 6 months of diagnosis were included. The control group contained women with breast cancer who had also undergone radiotherapy, but not to the pelvic area. Fine and Gray competing-risk analysis was used to calculate subhazard-rate ratios (subHRRs) and cumulative incidence functions (CIFs) for the risk of having a prosthesis accounting for differences in mortality.Results —
Of 962 eligible patients with gynecological cancer, 26 (3%) had received a total hip replacement. In the control group without exposure, 253 (3%) of 7,545 patients with breast cancer had undergone total hip replacement. The 8-year CIF for receiving a total hip replacement was 2.7% (95% CI: 2.6–2.8) for gynecological cancer patients and 3.0% (95% CI: 2.95–3.03) for breast cancer patients; subHRR was 0.80 (95% CI: 0.53–1.22; p = 0.3). In both groups, the most common reason for hip replacement was idiopathic osteoarthritis.Interpretation —
We did not find any statistically significantly higher risk of undergoing total hip replacement in patients with gynecological cancer who had had pelvic radiotherapy than in women with breast cancer who had not had pelvic radiotherapy.After approximately 5 years, two-thirds of cancer patients are still alive (Sant et al. 2009). Research on late adverse effects in cancer survivors has gained increasing interest over the last decade. However, the main interest has been on secondary cancer events (Curtis et al. 2006), cardiovascular complications, and emotional problems (Meyerowitz et al. 2008). The relationship between cancer, skeletal disorders, and treatment has rarely been investigated. Skeletal adverse effects of irradiation include cell death, cellular injury, and abnormal bone repair—although the underlying mechanisms are not fully understood (Yurut-Caloglu et al. 2010).Pelvic insufficiency fractures may be one of the possible late side effects of radiotherapy to the pelvic area. The incidence of such fractures has been reported to be 5–20% in gynecological cancer patients who have undergone radiotherapy (Kwon et al. 2008, Oh et al. 2008, Schmeler et al. 2010, Shih et al. 2013). Less common effects of pelvic irradiation include acetabular protrusion and avascular necrosis of the femoral head (Fiorino et al. 2009). Other studies have not found any increased risk of hip fracture after pelvic irradiation (Feltl et al. 2006, Elliott et al. 2011). We wanted to examine the risk of receiving a total hip replacement in patients with cancer in the pelvic area who had undergone radiotherapy compared to patients with cancer at another location who had not undergone pelvic irradiation. Our hypothesis was that patients who have had high-dose pelvic radiotherapy would have a higher risk of undergoing total hip replacement than women who have had radiotherapy with target fields in other parts of the body. 相似文献39.
Harrison H. Nguyen Hanson Fong Avina Paranjpe Natasha M. Flake James D. Johnson Ove A. Peters 《Journal of endodontics》2014
Introduction
The purpose of this study was to compare the fracture resistance to cyclic fatigue of ProTaper Next (PTN; Dentsply Tulsa Dental Specialties, Tulsa, OK), ProTaper Universal (PTU, Dentsply Tulsa Dental Specialties), and Vortex Blue (VB, Dentsply Tulsa Dental Specialties) rotary instruments.Methods
Twenty instruments each of PTN X1–X5, PTU S1–F5, and VB 20/04–50/04 were rotated until fracture in a simulated canal of 90° and a 5-mm radius using a custom-made testing platform. The number of cycles to fracture (NCF) was calculated. Weibull analysis was used to predict the maximum number of cycles when 99% of the instrument samples survive.Results
VB 20/04–30/04 had significantly higher NCF than PTU S1–F5 and PTN X1–X5. VB 35/04–45/04 had significantly higher NCF than PTU S2–F5 and PTN X2–X5. PTN X1 had higher NCF than PTU S1–F5. PTN X2 had higher NCF than PTU F2–F5. The Weibull distribution predicted the highest number of cycles at which 99% of instruments survive to be 766 cycles for VB 25/04 and the lowest to be 50 cycles for PTU F2.Conclusions
Under the limitations of this study, VB 20/04–45/04 were more resistant to cyclic fatigue than PTN X2–X5 and PTU S2–F5. PTN X1 and X2 were more resistant to cyclic fatigue than PTU F2–F5. The Weibull distribution appears to be a feasible and potentially clinically relevant model to predict resistance to cyclic fatigue. 相似文献40.
Paulo H. B. Brant Carvalho Pedro Ivo R. Moraes Alexandre A. Leito Ove Andersson Chris A. Tulk Jamie Molaison Alexander P. Lyubartsev Ulrich Hussermann 《RSC advances》2021,11(49):30744
Three amorphous forms of Ar hydrate were produced using the crystalline clathrate hydrate Ar·6.5H2O (structure II, Fdm, a ≈ 17.1 Å) as a precursor and structurally characterized by a combination of isotope substitution (36Ar) neutron diffraction and molecular dynamics (MD) simulations. The first form followed from the pressure-induced amorphization of the precursor at 1.5 GPa at 95 K and the second from isobaric annealing at 2 GPa and subsequent cooling back to 95 K. In analogy to amorphous ice, these amorphs are termed high-density amorphous (HDA) and very-high-density amorphous (VHDA), respectively. The third amorph (recovered amorphous, RA) was obtained when recovering VHDA to ambient pressure (at 95 K). The three amorphs have distinctly different structures. In HDA the distinction of the original two crystallographically different Ar guests is maintained as differently dense Ar–water hydration structures, which expresses itself in a split first diffraction peak in the neutron structure factor function. Relaxation of the local water structure during annealing produces a homogeneous hydration environment around Ar, which is accompanied with a densification by about 3%. Upon pressure release the homogeneous amorphous structure undergoes expansion by about 21%. Both VHDA and RA can be considered frozen solutions of immiscible Ar and water in which in average 15 and 11 water molecules, respectively, coordinate Ar out to 4 Å. The local water structures of HDA and VHDA Ar hydrates show some analogy to those of the corresponding amorphous ices, featuring H2O molecules in 5- and 6-fold coordination with neighboring molecules. However, they are considerably less dense. Most similarity is seen between RA and low density amorphous ice (LDA), which both feature strictly 4-coordinated H2O networks. It is inferred that, depending on the kind of clathrate structure and occupancy of cages, amorphous states produced from clathrate hydrates display variable local water structures.Three amorphous forms of Ar clathrate hydrate (pressure-amorphized, annealed and recovered) were characterized by isotope substitution (36Ar) neutron diffraction and molecular dynamics and their local coordinations analyzed and compared to pure ice. 相似文献