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BACKGROUND: To compare outcomes of revision to a long uncemented stem with cement-in-cement revision for Vancouver B2 periprosthetic fracture (PPF). METHODS: Patients undergoing surgery for a Vancouver B2 PPF in a cemented stem from 2008 to 2018 were identified using our prospectively collated database. RESULTS: We identified 43 uncemented and 29 cement-in-cement revisions. Cement-in-cement revision had a shorter operative time, reduction in certain complications, no increased rate of non-union, lower degree of stem subsidence and no difference in re-revision rate. CONCLUSION: With appropriate patient selection, both cement-in-cement and long uncemented stem revision represent appropriate treatment options for Vancouver B2 fractures.

Aims The aim of this study was to compare any differences in the primary outcome (biphasic flexion knee moment during gait) of robotic arm-assisted bi-unicompartmental knee arthroplasty (bi-UKA) with conventional mechanically aligned total knee arthroplasty (TKA) at one year post-surgery. Methods A total of 76 patients (34 bi-UKA and 42 TKA patients) were analyzed in a prospective, single-centre, randomized controlled trial. Flat ground shod gait analysis was performed preoperatively and one year postoperatively. Knee flexion moment was calculated from motion capture markers and force plates. The same setup determined proprioception outcomes during a joint position sense test and one-leg standing. Surgery allocation, surgeon, and secondary outcomes were analyzed for prediction of the primary outcome from a binary regression model. Results Both interventions were shown to be effective treatment options, with no significant differences shown between interventions for the primary outcome of this study (18/35 (51.4%) biphasic TKA patients vs 20/31 (64.5%) biphasic bi-UKA patients; p = 0.558). All outcomes were compared to an age-matched, healthy cohort that outperformed both groups, indicating residual deficits exists following surgery. Logistic regression analysis of primary outcome with secondary outcomes indicated that the most significant predictor of postoperative biphasic knee moments was preoperative knee moment profile and trochlear degradation (Outerbridge) (R2 = 0.381; p = 0.002, p = 0.046). A separate regression of alignment against primary outcome indicated significant bi-UKA femoral and tibial axial alignment (R2 = 0.352; p = 0.029), and TKA femoral sagittal alignment (R2 = 0.252; p = 0.016). The bi-UKA group showed a significant increased ability in the proprioceptive joint position test, but no difference was found in more dynamic testing of proprioception. Conclusion Robotic arm-assisted bi-UKA demonstrated equivalence to TKA in achieving a biphasic gait pattern after surgery for osteoarthritis of the knee. Both treatments are successful at improving gait, but both leave the patients with a functional limitation that is not present in healthy age-matched controls. Cite this article: Bone Joint J 2022;103-B(4):433–443.

This article concerns the ways in which authors from various fields conceptualise the ethical issues arising in the conduct of research. We reviewed critically and systematically the literature concerning the ethics of conducting research in order to engage in a reflection about the vocabulary and conceptual categories used in the publications reviewed. To understand better how the ethical issues involved in conducting research are conceptualised in the publications reviewed, we 1) established an inventory of the conceptualisations reviewed, and 2) we critically assessed them. We found that the publications reviewed mostly showed examples of descriptive ethics, in that most authors describe ethical issues without reflecting much on them, which could be explained both by 1) a lack of ethical education in research contexts, and 2) by the fact that we do not know what researchers know (or do not) about ethical issues. Additionally, the definitions identified in the publications are scarce and at times imprecise, but this seems more to point out the ethical vocabulary’s difficulties in certain contexts. Further, very few authors offer proper conceptualisations of the ethical issues arising in conducting research. When dealing with vast arrays of ethical issues to conceptualise, perhaps one ought to remember that some typologies already exist that could guide further reflection and help understand other realities for which the current ethical vocabulary may be lacking. We believe that combining the reviewed typologies, both with other well-developed typologies and critical reflection, could help support better ethical practice in conducting research.

Aqueous electrochemical atom transfer radical polymerisation (eATRP) can be challenging due to deleterious side reactions leading to the loss of the ω-chain end, increased rates of activation (k¬act) leading to higher [Pn˙] and increased rates of termination and lability of the X-CuII/L bond to hydrolysis leading to poor control. Here, we build on recent advances in eATRP methodology to develop a simplified current controlled eATRP of acrylamides in water. The simplification arises from the use of commercial, standardised reaction hardware which enables the polymerisations to be performed in a 2-electrode, ‘plug-n-play’, undivided electrochemical cell configuration. Further simplification is afforded by the design of a single stepwise current profile (Iapp vs time) capable of mediating current controlled eATRP of N-hydroethylacrylamide (HEAm). At room temperature, polymerisation of HEAm to target degrees of polymerisation (DPn,th¬) of 20 – 100 proceeds with good control (Ɖ ≤ 1.50). Loss of control when targeting higher DPn at room temperature is circumvented by lowering the reaction temperature (r.t. to 0 °C), increasing the stirring rate (400 rpm to 800 rpm) and increasing the catalyst concentration. Using the best conditions a linear increase in Mn,SEC with DPn (up to DPn = 320) and low dispersity values (DPn,th = 40 – 160; Ɖ = 1.26 – 1.38) are obtained. Furthermore, the current profile and reaction conditions can support the polymerisation of other primary and secondary acrylamides and the retention of the ω-Br chain end is exemplified by a short in situ chain extension. Overall, this represents further simplification of aqueous eATRP with respect to reaction set up and experimental parameters (single current profile) which has been employed synthesise polyacrylamides with good efficiency and control.

Simplified electrochemical atom transfer radical polymerization (seATRP) using CuII–N-propyl pyridineimine complexes (CuII(NPPI)2) is reported for the first time. In aqueous solution, using oligo(ethylene glycol) methyl ether methacrylate (OEGMA), standard electrolysis conditions yield POEGMA with good control over molecular weight distribution (Đm < 1.35). Interestingly, the polymerizations are not under complete electrochemical control, as monomer conversion continues when electrolysis is halted. Alternatively, it is shown that the extent and rate of polymerization depends upon an initial period of electrolysis. Thus, it is proposed that seATRP using CuII(NPPI)2 follows an electrochemically-triggered, rather than electrochemically mediated, ATRP mechanism, which distinguishes them from other CuIIL complexes that have been previously reported in the literature.

Objectives The aim of this multicentre retrospective study was to describe the clinical presentation, imaging findings, diagnosis and outcomes of cats with retrobulbar neoplasia. Methods A total of 37 cats that were diagnosed with retrobulbar neoplasia and underwent advanced imaging were recruited from searches of the clinical records of two referral hospitals. All cats had neoplasia confirmed via cytology or histopathology. Data relating to the signalment, presentation, results of investigations, treatment and outcome were recorded. A review of imaging studies was performed where possible. Results In total, 23 cases (62%) were presented with respiratory signs. Exophthalmos was the most common ophthalmological examination finding, present in 18 cases (49%). Thirty-two cases (86%) had secondary extension of neoplasia to the retrobulbar space (most commonly from the nasal cavities), present in 20 cases (54%), of which 12 were lymphoma. In cases where contrast was administered, 28/35 (80%) had contrast-enhancing masses. Orbital extension was detected in 21 cases (57%), exophthalmos in 22 (59%), globe deformation in 12 (32%) and local lymphadenomegaly in 22 (61%). In total, 36 (97%) retrobulbar tumours were malignant. Thoracic imaging, where it was performed, was concerning for metastasis in 8/25 cases (31%), with abdominal imaging suggestive of metastasis in 5/12 (42%). The most common diagnosis was lymphoma with 19 cases (51%), with nasal lymphoma representing 12 of these, followed by carcinoma in 10 (27%). The median survival time, for cases where death was recorded, was 85 days (range 1–263 days). Conclusions and relevance To the authors’ knowledge, this is the largest study of neoplasia affecting the feline retrobulbar space. Retrobulbar tumours in cats are overwhelmingly malignant, and commonly due to secondary extension of tumours originating elsewhere. Lymphoma, particularly arising from the nasal cavities, was the most common cause. Cats presenting with signs suggestive of retrobulbar disease should be assessed for disease affecting any of the structures of the head.

In the context of academic research, a diversity of ethical issues, conditioned by the different roles of members within these institutions, arise. Previous studies on this topic addressed mainly the perceptions of researchers. However, to our knowledge, no studies have explored the transversal ethical issues from a wider spectrum, including other members of academic institutions as the research ethics board (REB) members, and the research ethics experts. The present study used a descriptive phenomenological approach to document the ethical issues experienced by a heterogeneous group of Canadian researchers, REB members, and research ethics experts. Data collection involved socio-demographic questionnaires and individual semi-structured interviews. Following the triangulation of different perspectives (researchers, REB members and ethics experts), emerging ethical issues were synthesized in ten units of meaning: (1) research integrity, (2) conflicts of interest, (3) respect for research participants, (4) lack of supervision and power imbalances, (5) individualism and performance, (6) inadequate ethical guidance, (7) social injustices, (8) distributive injustices, (9) epistemic injustices, and (10) ethical distress. This study highlighted several problematic elements that can support the identification of future solutions to resolve transversal ethical issues in research that affect the heterogeneous members of the academic community.

FAIRplus seeks to establish ‘FAIRification’ processes that can be used at scale to ensure FAIRness of IMI data. The FAIRplus Sustainability White Paper discusses the approach that FAIRplus took to the sustainability of the core assets from the project and provides examples of the future sustainability plans for a number of the key deliverables including the FAIR Cookbook, Data set maturity (DSM) and Ethics best practices. The white paper also highlights challenges with sustainability in the current approach to projects in IHI/IMI and makes some recommendations.

Purpose: This study identified the individuals responsible for making decisions about physiotherapy (PT) wait time, frequency of treatment, and treatment duration for persons with low back pain and determined which factors guided these decisions. Method: A cross-sectional survey was sent to Canadian PT professionals treating adult patients with musculoskeletal problems. It included a clinical vignette describing a patient with low back pain. Respondents were asked who made decisions about wait time, treatment frequency, and treatment duration as well as on which factors they based these decisions. Results: Clinicians were most often responsible for making decisions about treatment frequency and duration. Although clinicians and managers or coordinators were mainly responsible for making decisions about wait time, there was more variability depending on sector of care: in the private sector, administrative assistants played a much larger role. Clinical judgment, clinical guidelines, and patients’ demands were the predominant factors influencing wait time and frequency decisions. Treatment duration was related to patients’ goals, clinical progression, patients’ motivation, and patients’ return to work. Conclusions: Decisions about service provision for wait times are made by a range of stakeholders, and a wide variety of factors guide Canadian PT professionals’ decision making. Identifying these factors is essential for informing a discussion of decisions about evidence-based and equitable service delivery so that the actors involved can reach a consensus.

A simplified ‘plug-and-play’ approach to aqueous electrochemical atom transfer radical polymerization (eATRP) has been developed. Well-controlled polymerization of PEGA480 (Đm = 1.17–1.31) is reported under potentiostatic (3-electrodes, undivided cell) and galvanostatic (2-electrodes, 6-steps) conditions.

Our study sought to (1) describe the practices and preferences of Colombian adolescents in accessing sexual and reproductive health services: accompanied versus alone; (2) compare actual practices with stated preferences; and (3) determine age and gender differences regarding the practice and these stated preferences.812 participants aged 11-24 years old answered a survey in two Profamilia clinics in the cities of Medellin and Cali in Colombia. A cross-sectional analysis was performed to compare participants' answers based on the variables of gender and age.A quarter of participants visited the clinic alone (25.4%). Females were more likely to go alone in comparison to males (26.3% vs 14.1%; p = 0.031), and older participants went alone more often than younger participants (p 0.001). Most participants - 72.7% (95 %CI: 69.3-75.9) - expressed a preference in being accompanied to the clinic, and more than 90% had their preferences met. The preferences of older participants were, however, less likely to be met than those of younger participants (p 0.001), notably, because they predominantly wanted to be accompanied.Contemporary public health and bioethics literature advocates in favor of developing health services that better meet the preferences of adolescents. The present research highlights an apparent blind spot related to the role that others (e.g., parents, friends, partners) can or should play in accompanying adolescent patients when they access sexual and reproductive health services. Respecting adolescents' preferences, and hence their autonomy, is not simply a matter of ensuring freedom from constraints (e.g., their right and ability to go alone). Rather, it should also consider the liberty to choose whether to be accompanied when accessing SHRS and by whom.

The introduction of pre-exposure prophylaxis (PrEP) for HIV has triggered critical analysis within the social sciences. For example, some have signalled how PrEP may lead to a renewed medicalisation of gay and other homosexually-active men’s sexuality. This chapter challenges some of those accounts. Adopting a public health ethics perspective, it argues that gay men should be understood as agentic in their use of PrEP, as opposed to being the passive victims of medicalisation, and that greater attention should be paid to questions of pleasure in PrEP use. Applying a reproductive justice framework, the chapter argues that the worldwide inaccessibility of PrEP constitutes a more serious ethical issue than the potential problem of the medicalisation of gay men’s sexuality.

This paper reports on the use of scanning ion conductance microscopy (SICM) to locally map the ionic properties and charge environment of two live bacterial strains: the Gram-negative Escherichia coli and the Gram-positive Bacillus subtilis. SICM results find heterogeneities across the bacterial surface and significant differences among the Gram-positive and Gram-negative bacteria. The bioelectrical environment of the B. subtilis was found to be considerably more negatively charged compared to E. coli. SICM measurements, fitted to a simplified finite element method (FEM) model, revealed surface charge values of -80 to -140 mC m-2 for the Gram-negative E. coli. The Gram-positive B. subtilis show a much higher conductivity around the cell wall, and surface charge values between -350 and -450 mC m-2 were found using the same simplified model. SICM was also able to detect regions of high negative charge near B. subtilis, not detected in the topographical SICM response and attributed to the extracellular polymeric substance. To further explore how the B. subtilis cell wall structure can influence the SICM current response, a more comprehensive FEM model, accounting for the physical properties of the Gram-positive cell wall, was developed. The new model provides a more realistic description of the cell wall and allows investigation of the relation between its key properties and SICM currents, building foundations to further investigate and improve understanding of the Gram-positive cellular microenvironment.

This paper reports on the use of scanning ion conductance microscopy (SICM) to locally map the ionic properties and charge environment of two live bacterial strains: the gramnegative Escherichia coli and the gram-positive Bacillus subtilis. SICM results find heterogeneities across the bacterial surface, and significant differences among the grampositive and -negative bacteria. The bioelectrical environment of the B. subtilis was found to be considerably more negatively charged compared to E. coli. SICM measurements, fitted to a simplified finite element method (FEM) model, revealed surface charge values of −80 to −140 mC m−2 for the gram-negative E. coli. The gram-positive B. subtilis show a much higher conductivity around the cell wall, and surface charge values between −350 and −450 mC m−2 were found using the same simplified model. SICM was also able to detect regions of high negative charge near B. subtilis, not detected in the topographical SICM response and attributed to extracellular polymeric substance. To further explore how the B. subtilis cell wall structure can influence the SICM current response, a more comprehensive FEM model, accounting for the physical properties of the gram-positive cell wall, was developed. The new model provides a more realistic description of the cell wall and allowed investigation of the relation between its key properties and SICM currents, building foundations to further investigate and improve understanding of the gram-positive cellular microenvironment.Abstract Figure

A TV debate in April 2020 between two French doctors regarding the benefits of testing a coronavirus vaccine in Africa where there are no masks or treatments available has led to international criticism. This case highlights a problematic ethical double standard in multinational clinical research: trials that would be considered unethical in high income countries (e.g., placebo-controlled where there is an existing treatment) are nonetheless justified in low-and-middle-income countries because the existing standards of care are less (i.e., no access to a treatment). Underlying this ethical double standard in some multinational clinical trials is a moral imperialism and persistent colonialist thinking that must be rejected.

The availability of predictions of future system inputs has motivated research into preview control to improve set-point tracking and disturbance rejection beyond that achievable via conventional feedback control. The design of preview controllers, typically based upon model predictive control (MPC) for its constraint handling properties, is often performed in a monolithic nature, coupling the feedback and feed-forward problems. This can create problems, such as: (i) an additional feedback loop is introduced by MPC, which alters the closed-loop dynamics of the existing feedback compensator, potentially resulting in a deterioration of the nominal sensitivities and robustness properties of an existing closed-loop and (ii) the default preview action from MPC can be poor, degrading the original feedback control performance. In our previous work, the former problem is addressed by presenting a modular MPC design on top of a given output-feedback controller, which retains the nominal closed-loop robustness and frequency-domain properties of the latter, despite the addition of the preview design. In this paper, we address the second problem, the preview compensator design in the modular MPC formulation. Specifically, we derive the key conditions that ensure, under a given closed-loop tuning, the preview compensator within the modular MPC formulation is systematic and well-designed in a sense that the preview control actions complement the existing feedback control law rather than opposing it. In addition, we also derive some important results, showing that the modular MPC can be implemented in a cascade over any given linear controllers and the proposed conditions hold, regardless of the observer design for the modular MPC. The key benefit of the modular MPC is that the preview control with constraint handling can be implemented without replacing the existing feedback controller. This is illustrated through some numerical examples.

There has been increasing attention to financial conflicts of interest (COI) in public health research and policy making, with concerns that some decisions are not in the public interest. One notable problematic area is expert advisory committee (EAC). While COI management has focused on disclosure, it could go further and assess experts' degree of (in)dependence with commercial interests. We analyzed COI disclosures of members of Québec's immunization EAC (in Canada) using (In)DepScale, a tool we developed for assessing experts' level of (in)dependence. We found great variability of independence with industry and that companies with the highest vaccine sales were predominantly associated with disclosed COIs. We argue that EACs can use the (In)DepScale to better assess and disclose the COIs that affect their experts. Going forward our scale could help manage risk and select members who are less conflicted to foster a culture of transparency and trust in advisors and policy-makers.

The ethics of safe sex in the gay community has, for many years, been focused on debates surrounding the responsibility (or lack thereof) regarding the use of condoms to prevent HIV transmission, once the only tool available. With the development of Truvada as a pre-exposure prophylaxis (PrEP) for HIV, for the first time in the history of the HIV/AIDS epidemic there is the potential to significantly reduce the risk of HIV transmission during sex without the use of condoms (without taking into consideration ‘treatment as prevention’ with HIV-positive people). The introduction of PrEP necessitates a renewed discussion about the politics and ethics of safe sex for men who have sex with men (MSM). We present the arguments of authors who hold radically opposite positions with regard to the ethics of condom use by gay men, but who currently both criticize the use of PrEP. We offer a critique of their arguments and advance the position that the use of PrEP, even without condoms, can be acceptable and part of a safe sex ethics framework for MSM.