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Taper connections of modular hip prostheses are at risk of fretting and corrosion, which can result in reduced implant survival. The purpose of this study was to identify the minimum torque required to initiate a removal of the passivation layer at the taper interface as a function of assembly force and axial load.Titanium stems and cobalt–chromium heads were assembled with peak impaction forces of 4.5kN or 6.0kN and then mounted on a materials testing machine whilst immersed in Ringer's solution. The stems were subjected to a static axial load (1kN or 3kN) along the taper axis. After a period of equilibration, a torque ramp from 0 to 15Nm was manually applied and the galvanic potential was continuously recorded.Prostheses assembled with a force of 6kN required a significantly higher torque to start a removal of the passivation layer compared to those assembled with 4.5kN (7.23±0.55Nm vs. 3.92±0.97Nm,p=0.029). No influence of the axial load on the fretting behaviour was found (p=0.486).The torque levels, which were demonstrated to initiate surface damage under either assembly force, can be readily reached during activities of daily living. The damage will be intensified in situations of large weight and high activity of the patient or malpositioning of the prosthesis. [ABSTRACT FROM AUTHOR]

Background: Advances in haemolytic disease of the fetus and newborn have led to numerous treatment options. We report practice variations in the management and outcomes of haemolytic disease of the fetus and newborn in at-risk pregnancies., Methods: In this international, retrospective, observational cohort study, data from cases with moderate or severe haemolytic disease of the fetus and newborn were retrieved from 31 centres in 22 countries. Eligible participants had pregnancies with haemolytic disease of the fetus that led to fetal death at 16 + 0 weeks or later, those treated antenatally with intrauterine transfusion or intravenous immunoglobulins, or neonates without antenatal treatment who were treated with intensive phototherapy, exchange transfusion, or red blood cell transfusions. All patients had confirmed maternal alloantibodies and an antigen-positive fetus incompatible with the maternal alloantibody. Patients with ABO-incompatibility only were excluded. We assessed serological diagnostics and referrals, antenatal treatment and timing, complications, delivery route, and gestational age at birth. Outcomes were analysed in all eligible participants who had complete data available., Findings: 2443 pregnancies with haemolytic disease of the fetus and newborn treated between Jan 1, 2006, and July 1, 2021, were shared by the centres and analysed between Dec 1, 2021, and March 1, 2023. 23 pregnancies were excluded due to missing information and we included 2420 for further analysis. 1764 (72·9%) of 2420 pregnancies were affected by D-antibodies. 95 (3·9%) of 2420 pregnancies resulted in fetal death. Of the 2325 liveborn neonates, 1349 (58·1%) received any form of antenatal treatment and 976 (41·9%) were only treated postnatally. Median gestational age at referral was 20·4 weeks (IQR 14·9-28·0) and ranged between medians of 10·0 and 26·3 weeks between centres. Severe hydrops at first intrauterine transfusion was present in 185 (14·5%) of 1276 pregnancies, with proportions ranging between 0 and 42% between centres. A median of two intrauterine transfusions (IQR 1-4) were done per pregnancy. The fetal access sites used in intrauterine transfusions varied widely between centres. Non-lethal complications in intrauterine transfusions by transfusion site occurred at a lower rate in intrahepatic approaches (2·0%, 95% CI 1·1-3·3) than in placental insertion (6·9%, 5·8-8·0) and free loop (13·3%, 8·9-18·9). The use and indication for intravenous immunoglobulin administration varied widely. Neonates with intrauterine transfusion were born at a median gestational age of 35·6 weeks (IQR 34·0-36·7), ranging between medians of 33·2 and 37·3 weeks between centres, while neonates without antenatal treatment were born at a median gestational age of 37·3 (IQR 36·3-38·1), ranging between medians of 34·9 and 38·9 weeks between centres., Interpretation: We found considerable variation in antenatal management and outcomes in haemolytic disease of the fetus and newborn between sites in different countries. Our study shows the capacity of the field to gather valuable data on a rare disease and to optimise care., Funding: None., Competing Interests: Declaration of interests DPdW is doing a PhD programme partly funded by Momenta Pharmaceuticals, which was acquired by Johnson & Johnson, and is an investigator for a phase 2 trial (NCT03842189) of a new drug for the treatment of haemolytic disease of the fetus and newborn. EL is a sub-investigator for a phase 2 trial (NCT03842189) of a new drug for the treatment of haemolytic disease of the fetus and newborn, which is sponsored by Janssen Pharmaceuticals. RD reports paid lectures and participation in studies for Janssen Pharmaceuticals. PM received payment for a lecture from CSL Behrin. PM and J-MJ reports participation in an advisory board for haemolytic disease of the fetus and newborn of Janssen Pharmaceuticals in December, 2023, and both report participation in a phase 3 trial (NCT05912517) of a new drug for the treatment of haemolytic disease of the fetus and newborn, which is sponsored by Janssen Pharmaceuticals. ET is the principal investigator for Janssen-sponsored trials Unity and Clarity in Sweden and an advisory Board Member and Steering Committee member for Janssen Pharmaceutical on haemolytic disease of the fetus and newborn and FNAIT programmes. TPS is a member of the board of the International Society of The Fetus as a Patient and member of the expert committee for Gynaecology and Obstetrics at Ministry of Health, Republic of Slovenia. EJTV is the principal investigator for a phase 2 trial (NCT03842189) and phase 3 trial (NCT05912517) of a new drug for the treatment of haemolytic disease of the fetus and newborn, which is sponsored by Janssen Pharmaceuticals. All other authors report no competing interests or financial disclosures., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Triple-negative breast cancer (TNBC) is a group of very aggressive breast tumours, characterised by lack of expression of oestrogen receptor (ER), progesterone receptor (PR) and erb-b2 receptor tyrosine kinase 2 (ERBB2/HER2). Nevertheless, TNBCs show different clinical characteristics and are very diverse regarding prognostic outcome. So far, only a few prognostic markers for TNBC have been reported that could be helpful for therapeutic stratification. Here we have analysed the expression of S100P and HYAL2 using immunohistochemistry (IHC) in a TNBC cohort of 98 patients with a follow-up for recurrence and death. TNBC patients with high expression of both proteins showed significantly shorter progression-free survival (PFS) (mean PFS=35.9months, P=0.001) compared to TNBC patients with high expression levels of only one of the proteins (mean PFS=69.4months) and to TNBC patients with low expression of both proteins (mean PFS=83.3months). Moreover, multivariate Cox-regression model showed the combined expression of S100P and HYAL2 as independent prognostic factor for PFS (P=0.001). The expression of S100P and HYAL2 indicated similar prognostic effect to the overall survival (OS) of TNBC patients. In addition, high expression levels of both S100P and HYAL2 showed significant association with different clinicopathological characteristics, such as more recurrence events (P=0.004), and higher occurrence of metastasis (P=0.002). Our study proposes S100P and HYAL2 as potential prognostic markers for TNBC., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Introduction: Patients with a fracture in the anterior pelvic ring often simultaneously demonstrate pain in the posterior pelvic ring. The aim of the present prospective study was to assess the sensitivity of CT, MRI and clinical examination in the detection of fractures in the posterior pelvic ring in patients with fractures of the anterior pelvic ring diagnosed in conventional radiographs., Methods: Sixty patients with radiographic signs of an anterior pelvic ring injury were included in this prospective analysis. Following a focused clinical examination of the posterior pelvis, all patients underwent both a CT and then a MRI scan of their pelvis. Two board certified radiologists evaluated the CT and MRI scans independently. To estimate the presence of osteoporosis the Hounsfield units of the vertebral body of L5 were measured in each case., Results: Fifty-three women and seven men, with a mean age of 74.7+/-15.6 years were included into the study. A fracture of the posterior pelvic ring was found in fourty-eight patients (80%) patients using MRI. Fractures of the posterior pelvic ring would have been missed in eight cases (17%), if only CT had been used. Eighty-five percent of the patients with a posterior fracture had an osteoporosis. The majority of the cases suffered from a low energy trauma. Thirty-eight patients (83%) with positive clinical signs at the posterior pelvic ring actually had a fracture of the posterior pelvic ring in the MRI. The clinical examination proved to be equally effective to CT in detecting posterior pelvic ring fractures., Conclusion: The significance of both, clinical examination and CT was confirmed in the detection of fractures in the posterior pelvic ring. MRI examination of the pelvis however, was found to be superior in detecting undislocated fractures in a cohort of patients with a high incidence of osteoporosis. Using MRI may be beneficial in select cases, especially when reduced bone density is suspected., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Several bi-modular hip prostheses exhibit an elevated number of fretting-related postoperative complications most probably caused by excessive micromotions at taper connections. This study investigated micromotions at the stem-neck interface of two different designs: one design (Metha, Aesculap AG) has demonstrated a substantial number of in vivo neck fractures for Ti-Ti couplings, but there are no documented fractures for Ti-CoCr couplings. Conversely, for a comparable design (H-Max M, Limacorporate) with a Ti-Ti coupling only one clinical failure has been reported. Prostheses were mechanically tested and the micromotions were recorded using a contactless measurement system. For Ti-Ti couplings, the Metha prosthesis showed a trend towards higher micromotions compared to the H-Max M (6.5 ± 1.6 μm vs. 3.6 ± 1.5 μm, p=0.08). Independent of the design, prostheses with Ti neck adapter caused significantly higher interface micromotions than those with CoCr ones (5.1 ± 2.1 μm vs. 0.8 ± 1.6 μm, p=0.001). No differences in micromotions between the Metha prosthesis with CoCr neck and the H-Max M with Ti neck were observed (2.6 ± 2.0 μm, p=0.25). The material coupling and the design are both crucial for the micromotions magnitude. The extent of micromotions seems to correspond to the number of clinically observed fractures and confirm the relationship between those and the occurrence of fretting corrosion., (Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.)

Background: Traumatic acromioclavicular (AC) joint dislocations can be addressed with several surgical stabilization techniques. The aim of this in vitro study was to evaluate biomechanical features of the native joint compared with 3 different stabilization methods: locking hook plate (HP), TightRope (TR), and bone anchor system (AS)., Hypothesis: The HP provides higher stiffness than the anatomic reconstruction techniques., Study Design: Controlled laboratory study., Methods: A new biomechanical in vitro model of the AC joint was used to analyze joint stability after surgical repair (HP, TR, and AS). Eighteen cadaveric specimens were randomized for bone density and diameter in the midclavicle section. Joint stiffness was measured by applying an axial load and a defined physiological range of motion for internal and external rotations and upward and downward rotations. Data were recorded at 3 stages: for the native joint after dissecting the AC ligaments, directly after repair, and after axial cyclic loading (1000 cycles with 20 and 70 N at 1 Hz). To evaluate which implant mimics physiological joint properties best, axial stiffness of vertical stability was assessed in combination with rotation. Finally, static loading in the superior direction was applied until failure of the joints occurred., Results: Axial stiffness of the TR and AS groups was 2-fold higher than for the HP group and the native joint (67.1, 66.1, and 22.5 N/mm, respectively; P < .004). Decreased load-to-failure rates were recorded in the HP group compared with the TR and AS groups (248.9 ± 72.7, 832.0 ± 401.4, and 538.0 ± 166.1 N, respectively). The stiffness of the rotations was not significantly different between the treatment methods but was lower in horizontal and downward rotations compared with the native state. Thus, native AC ligaments contributed a significant share to joint stiffness., Conclusion: The TR and AS groups demonstrated higher vertical load capacity. Compared with the TR and AS, the HP demonstrated an axial stiffness closest to the native joint. For restoring physiological properties, reconstruction of the AC ligaments may be necessary., Clinical Relevance: The results show different biomechanical properties of the HP and anatomic reconstructions.

Modularity of femoral stems and neck components has become a more frequently used tool for an optimized restoration of the hip joint center and improvement of patient biomechanics. The additional taper interface increases the risk of mechanical failure due to fretting and crevice corrosion. Several failures of titanium alloy neck adapters have been documented in case-reports. An experimental fretting device was developed in this study to systematically investigate the effect of micromotion and contact pressure on fretting damage in contact situations similar to taper interfaces of modular hip prostheses under cyclic loading representative of in vivo load conditions. As a first application, the fretting behavior of Ti-6Al-4V titanium alloy components was investigated. Micromotions were varied between 10μm and 50μm, maximum contact pressures between 400 and 860N/mm(2). All modes of fretting damage were observed: Fretting wear was found for high micromotions in combination with low contact pressures. Fretting fatigue occurred with reduced movement or increased contact pressures. With small micromotions or high normal pressures, low fretting damage was observed. The developed device can be used to evaluate taper design (and especially contact geometry) as well as different materials prior to clinical use., (Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.)

Hip prostheses with a modular neck exhibit, compared to monobloc prostheses, an additional interface which bears the risk of fretting as well as corrosion. Failures at the neck adapter of modular prostheses have been observed for a number of different designs. It has been speculated that micromotions at the stem-neck interface were responsible for these implant failures. The purpose of this study was to investigate the influence of material combinations and assembly conditions on the magnitude of micromotions at the stem-neck interface during cyclic loading. Modular (n = 24) and monobloc (n = 3) hip prostheses of a similar design (Metha, Aesculap AG, Tuttlingen, Germany) were subjected to mechanical testing according to ISO 7206-4 (F(min) = 230N, F(max) = 2300N, f = 1Hz, n = 10,000 cycles). The neck adapters (Ti-6Al-4V or Co-Cr29-Mo alloy) were assembled with a clean or contaminated interface. The micromotion between stem and neck adapter was calculated at five reference points based on the measurements of the three eddy current sensors. The largest micromotions were observed at the lateral edge of the stem-neck taper connection, which is in accordance with the crack location of clinically failed prostheses. Titanium neck adapters showed significantly larger micromotions than cobalt-chromium neck adapters (p = 0.005). Contaminated interfaces also exhibited significantly larger micromotions (p < 0.001). Since excessive micromotions at the stem-neck interface might be involved in the process of implant failure, special care should be taken to clean the interface prior to assembly and titanium neck adapters with titanium stems should generally be used with caution., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The "Moegeldorfer Group", an initiative group integrating disabled and non-disabled persons, had been studied using qualitative interviewing techniques. The following motives and effects of group involvement have been found: Predominant among the disabled members had been the recreational opportunities offered by the group, along with the possibility of coming to know people who could help them outside group activities as well. Getting acquainted with disabled persons had been in the foreground among the non-disabled members. Their major problem, apart from rendering assistance, had been to become aware of, and learn to cope with, disability-related communication barriers. The voluntary encounter of disabled and non-disabled people is considered a positive first step towards changing the relationship between disabled and non-disabled persons as it exists in our society.