Search

Ilio-psoas impingement after total hip arthroplasty often occurs with the metallic rim of the acetabular cup. The main causes are poor cup anteversion or anterior wall defect. We firstly report here the case of a patient complaining of iliopsoas impingement due to contact with the liner of a dual-mobility device. Ultrasonography and Computed Tomographic scan clearly showed the direct mechanical contact of the dual-mobility liner with the iliopsoas tendon.

Background: Hip osteoarthritis (OA) can cause pain, restricted locomotor activity and functional impairments but it remains difficult to predict functional decline over time., Objectives: The aims of this study were to identify functional decline trajectories in people with hip OA using the Hip disability and Osteoarthritis Outcome Score (HOOS) domains and to determine radiological and gait predictors of typical trajectories., Methods: Consecutive people with hip OA with no indication for total hip replacement at baseline were included. Radiological, clinical (HOOS) and gait analyses were collected at baseline, and clinical follow-up was carried out every 6 months for 3 years. HOOS trajectories were estimated by group-based trajectory modeling. Predictive factors were identified by multivariate logistic regression, and their discriminatory power was assessed using the area under the ROC (receiver operating characteristic) curve., Results: Two distinct trajectories were highlighted for all HOOS domains: Traj1 (progressor) and Traj2 (non-progressor). Using a multivariate analysis, gait speed was found to be predictive of Traj1 for HOOS symptoms/stiffness (odds ratio [OR] 0.61, 95 % CI 0.45 to 0.83, AUC (area under the curve) = 75 %) and for HOOS pain (OR = 0.72, 95 % CI 0.53 to 0.97, AUC = 72 %). Moreover, maximum hip extension was found to be predictive of Traj1 for HOOS sports and leisure (OR = 0.78, 95 % CI 0.69 to 0.89, AUC = 81 %) and HOOS quality of life (OR = 0.84, 95 % CI 0.73 to 0.95, AUC = 66 %)., Conclusion: This study identified 2 typical trajectories of functional decline (progressor/non-progressor) for the 5 HOOS domains. It also demonstrated the predictive validity of 2 gait parameters (gait speed and maximum hip extension) for functional decline., Database Registration: NCT02042586., Competing Interests: Conflict of interest The authors have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

In plants, the first interaction between the pollen grain and the epidermal cells of the stigma is crucial for successful reproduction. When the pollen is accepted, it germinates, producing a tube that transports the two sperm cells to the ovules for fertilization. Confocal microscopy has been used to characterize the behavior of stigmatic cells post-pollination [1], but it is time-consuming since it requires the development of a range of fluorescent marker lines. Here, we propose a quick, high-resolution imaging protocol using tabletop scanning electron microscopy. This technique does not require prior sample fixation or fluorescent marker lines. It effectively captures pollen grain behavior from early hydration (a few minutes after pollination) to pollen tube growth within the stigma (1 h after pollination) and is particularly efficient for tracking pollen tube paths. Key features • Analysis of the pollen behavior in stigmatic cells of Arabidopsis thaliana but can be broadly used for other species. • Rapid and high-resolution imaging method. • Allows testing pollen grain hydration states, pollen tube paths on stigmatic cells from various genetic backgrounds, and also pollen tube phenotypes., Competing Interests: Competing interestsThe authors declare no competing interests., (©Copyright : © 2024 The Authors; This is an open access article under the CC BY license.)

Both the pollen tube and hyphae of filamentous pathogens penetrate the outer layer of the host and then grow within host tissues. Early epidermal responses are decisive for the outcome of these two-cell interaction processes. We identified a single cell type, the papilla in the stigma of Arabidospis, as a tool to conduct a comprehensive comparative analysis on how an epidermal cell responds to the invasion of an unwanted pathogen or a welcome pollen tube. We showed that Phytophtora parasitica, a root oomycete, effectively breaches the stigmatic cell wall and develops as a biotroph within the papilla cytoplasm. These invasive features resemble the behaviour exhibited by the pathogen within its natural host cell, but diverge from the manner in which the pollen tube progresses, being engulfed within the papilla cell wall. Quantitative analysis revealed that both invaders trigger reorganization of the stigmatic endomembrane system and the actin cytoskeleton. While some remodelling processes are shared between the two interactions, others appear more specific towards the respective invader. These findings underscore the remarkable ability of an epidermal cell to differentiate between two types of invaders, thereby enabling it to trigger the most suitable response during the onset of invasion., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Sagittal balance, commonly impaired in lumbar spinal stenosis (LSS) patients, is typically assessed using the sagittal vertical axis (SVA) with EOS imaging. However, to limit X-ray exposure and medical costs, it could be interesting to evaluate the capacity of quantified motion analysis to estimate the 3D modeling of SVA in patients with symptomatic LSS., Methods: An estimation of the SVA in patients with LSS was performed with 3D motion analysis. SVA and "C7&#95;PSI" (orthogonal horizontal distance between the vertical lines through the markers of the C7 vertebra and the middle of the posterosuperior iliac spine) were measured on 37 LSS patients using EOS radiography and postural and 3D motion analysis, respectively. Multiple stepwise linear regressions were performed with EOS SVA according to age, body mass index, C7&#95;PSI and/or postural variables., Results: A highly significant relationship was found between SVA and C7&#95;PSI, mediolateral amplitude of CoP displacements and age (adjusted R²=0.69, p < 0.0001). While the postural analysis did not reveal significant relationships, the model using 3D parameters revealed significant relationships between radiographic SVA and C7&#95;PSI and age (adjusted R²=0.65, p < 0.0001). 3D motion parameters with or without postural parameters may explain more than 65% of the variance seen in EOS imaging performed on LSS patients., Conclusions: These promising results in LSS patients suggest that the estimation of SVA with 3D motion analysis offers an alternative to EOS. In addition, SVA could be assessed at rest and during dynamic tasks., Trial Registration: This study has been published in Clinical Trial registration (reference NCT03194607)., (© 2024. The Author(s).)

Background: A mobile polyethylene liner enables the dual mobility cup (DMC) to contribute to restoring hip joint range-of-motion, decreasing wear and increasing implant stability. However, more data is required on how liner orientation changes with hip joint movement. As a first step towards better understanding liner orientation change in vivo, this cadaver study focuses on quantifying DMC liner orientation change after different hip passive movements, using ultrasound imaging and motion analysis., Hypothesis: The liner does not always go back to its initial orientation and its final orientation depends mainly on hip movement amplitude., Methods: 3D ultrasound imaging and motion analysis were used to define liner and hip movements for four fresh post-mortem human subjects with six implanted DMC. Abduction and anteversion angles of the liner plane relative to the pelvis were measured before and after hip flexion, internal rotation, external rotation, abduction, adduction., Results: Liner orientation changes were generally defined by angle variation smaller than 5°, with the liner nearly going back to its initial orientation. However, hip flexion caused liner abduction and anteversion angle variations greater than 15°. Except for hip adduction, only weak or no correlation was found between the final angle of the liner and the maximal hip joint movement amplitude., Discussion: This study is the first attempt to quantify liner orientation change for implanted DMC via ultrasound imaging and constitutes a step forward in the understanding of liner orientation change and its relationship with hip joint movement. The hypothesis that the final liner abduction and anteversion angles depend mainly on hip movement amplitude was not confirmed, even if hip flexion was the movement generating the most liner orientation changes over 15°. This approach should be extended to in vivo clinical investigations, as measured liner angle variation could provide important support for the wear and stability claims made for DMC., Level of Evidence: IV; cadaveric study., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Colorful flower patterns are key signals to attract pollinators. To produce such motifs, plants specify boundaries dividing petals into subdomains where cells develop distinctive pigmentations, shapes, and textures. While some transcription factors and biosynthetic pathways behind these characteristics are well studied, the upstream processes restricting their activities to specific petal regions remain enigmatic. Here, we unveil that the petal surface of Hibiscus trionum , an emerging model featuring a bullseye on its corolla, is prepatterned as the bullseye boundary position is specified long before it becomes visible. Using a computational model, we explore how pattern proportions are maintained while petals experience a 100-fold size increase. Exploiting transgenic lines and natural variants, we show that plants can regulate boundary position during the prepatterning phase or modulate growth on either side of this boundary later in development to vary bullseye proportions. Such modifications are functionally relevant, as buff-tailed bumblebees can reliably identify food sources based on bullseye size and prefer certain pattern proportions.

Running is the basis of many sports and has highly beneficial effects on health. To increase the understanding of running, DSPro ® insoles were developed to collect running parameters during tasks. However, no validation has been carried out for running gait analysis. The aims of this study were to assess the test-retest reliability and criterion validity of running gait parameters from DSPro ® insoles compared to a motion-capture system. Equipped with DSPro ® insoles, a running gait analysis was performed on 30 healthy participants during overground and treadmill running using a motion-capture system. Using an intraclass correlation coefficient (ICC), the criterion validity and test-retest reliability of spatiotemporal parameters were calculated. The test-retest reliability shows moderate to excellent ICC values (ICC > 0.50) except for propulsion time during overground running at a fast speed with the motion-capture system. The criterion validity highlights a validation of running parameters regardless of speeds (ICC > 0.70). This present study validates the good criterion validity and test-retest reliability of DSPro ® insoles for measuring spatiotemporal running gait parameters. Without the constraints of a 3D motion-capture system, such insoles seem to be helpful and relevant for improving the care management of active patients or following running performance in sports contexts.

Used on clinical and sportive context, three-dimensional motion analysis is considered as the gold standard in the biomechanics field. The proposed dataset has been established on 30 asymptomatic young participants. Volunteers were asked to walk at slow, comfortable and fast speeds, and to run at comfortable and fast speeds on overground and treadmill using shoes. Three dimensional trajectories of 63 reflective markers, 3D ground reaction forces and moments were simultaneously recorded. A total of 4840 and 18159 gait cycles were measured for overground and treadmill walking, respectively. Additionally, 2931 and 18945 cycles were measured for overground and treadmill running, respectively. The dataset is presented in C3D and CSV files either in raw or pre-processed format. The aim of this dataset is to provide a complete set of data that will help for the gait characterization during clinical gait analysis and in a sportive context. This data could be used for the creation of a baseline database for clinical purposes to research activities exploring the gait and the run., (© 2024. The Author(s).)

Wireless wearable insoles are interesting tools to collect gait parameters during daily life activities. However, studies have to be performed specifically for each type of insoles on a big data set to validate the measurement in ecological situations. This study aims to assess the criterion validity and test-retest reliability of gait parameters from wearable insoles compared to motion capture system. Gait of 30 healthy participants was recorded using DSPro ® insoles and a motion capture system during overground and treadmill walking at three different speeds. Criterion validity and test-retest reliability of spatio-temporal parameters were estimated with an intraclass correlation coefficient (ICC). For both systems, reliability was found higher than 0.70 for all variables ( p < 0.001) except for minimum toe clearance (ICC < 0.50) with motion capture system during overground walking. Regardless of speed and condition of walking, Speed, Cadence, Stride Length, Stride Time and Stance Time variables were validated (ICC > 0.90; p < 0.001). During walking on treadmill, loading time was not validated during slow speed (ICC < 0.70). This study highlights good criterion validity and test-retest reliability of spatiotemporal gait parameters measurement using wearable insoles and opens a new possibility to improve care management of patients using clinical gait analysis in daily life activities.

In plants, the first interaction that occurs between the male gametophytes (pollen grains) and the stigmatic epidermis of the female organ is crucial for successful reproduction. The stigma consists of a dome of flask-shaped cells specialized in pollen capture. In these stigmatic cells, the cytoskeleton network (cortical microtubules and actin microfilaments) actively responds to pollen contact and undergoes dynamic remodeling required for successful pollen acceptance to occur. Here, we have designed several microscopy mountings to monitor stigmatic cytoskeleton dynamics. These designs are based on the constraints linked to the tightly regulated pollen-stigma interaction and depend upon the experimental goal, either a static view or live-cell imaging., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The Dual Mobility Cup (DMC) was created in 1974 to prevent dislocation and decrease wear. However, the movement of the polyethylene liner in vivo remains unclear. The aims of this study were to visualise liner positions and quantify the accuracy of the liner plane orientation for static positions, using ultrasound imaging. DMC reconstruction and angle between cup and liner were evaluated on isolated submerged DMCs by comparing 3D laser scans and ultrasound imaging. Moreover, the abduction and anteversion angles of the liner plane relative to the pelvis orientation were calculated via combined motion analysis and 3D ultrasound imaging on four fresh post-mortem human subjects with implanted DMC. On submerged DMC, the mean angle error between ultrasound imaging and 3D scan was 1.2°. In cadaveric experiments, intra-operator repeatability proved satisfactory, with low range value (lower than 2°) and standard deviation (lower than 1°). The study demonstrates the feasibility of measuring liner orientation on submerged and ex vivo experiments using ultrasound imaging, and is a first step towards in vivo analysis of DMC movement., Competing Interests: Declaration of Competing Interest AV is a consultant for Serf and Smith & Nephew and M-HF receives royalties from Serf and DePuy. LR, AN, TDL, HL, RD, and L-LG declare no conflict of interest., (Copyright © 2022. Published by Elsevier Ltd.)

Plant epidermis are multifunctional surfaces that directly affect how plants interact with animals or microorganisms and influence their ability to harvest or protect from abiotic factors. To do this, plants rely on minuscule structures that confer remarkable properties to their outer layer. These microscopic features emerge from the hierarchical organization of epidermal cells with various shapes and dimensions combined with different elaborations of the cuticle, a protective film that covers plant surfaces. Understanding the properties and functions of those tridimensional elements as well as disentangling the mechanisms that control their formation and spatial distribution warrant a multidisciplinary approach. Here we show how interdisciplinary efforts of coupling modern tools of experimental biology, physics, and chemistry with advanced computational modeling and state-of-the art microscopy are yielding broad new insights into the seemingly arcane patterning processes that sculpt the outer layer of plants., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

Following pollen deposition on the receptive surface of the stigma, pollen germinates a tube that carries male gametes toward the ovule where fertilization occurs. As soon as it emerges from the pollen grain, the pollen tube has to be properly guided through the pistil tissues so as to reach the ovule and ensure double fertilization. Chemical attractants, nutrients as well as receptor kinase-dependent signaling pathways have been implicated in this guidance. Recently, we showed in Arabidopsis that the microtubule severing enzyme KATANIN, by acting both on cortical microtubule (CMT) dynamics and cellulose microfibril (CMF) deposition, conferred particular mechanical properties to the papilla cell wall that act as active guidance factors. Here we confirm the importance of KATANIN and CMT orientation in pollen tube directionality by examining another katanin mutant.

Background: Fertilization in flowering plants depends on the early contact and acceptance of pollen grains by the receptive papilla cells of the stigma. Deciphering the specific transcriptomic response of both pollen and stigmatic cells during their interaction constitutes an important challenge to better our understanding of this cell recognition event., Results: Here we describe a transcriptomic analysis based on single nucleotide polymorphisms (SNPs) present in two Arabidopsis thaliana accessions, one used as female and the other as male. This strategy allowed us to distinguish 80% of transcripts according to their parental origins. We also developed a tool which predicts male/female specific expression for genes without SNP. We report an unanticipated transcriptional activity triggered in stigma upon incompatible pollination and show that following compatible interaction, components of the pattern-triggered immunity (PTI) pathway are induced on the female side., Conclusions: Our work unveils the molecular signatures of compatible and incompatible pollinations both at the male and female side. We provide invaluable resource and tools to identify potential new molecular players involved in pollen-stigma interaction.

Successful fertilization in angiosperms depends on the proper trajectory of pollen tubes through the pistil tissues to reach the ovules. Pollen tubes first grow within the cell wall of the papilla cells, applying pressure to the cell. Mechanical forces are known to play a major role in plant cell shape by controlling the orientation of cortical microtubules (CMTs), which in turn mediate deposition of cellulose microfibrils (CMFs). Here, by combining imaging, genetic and chemical approaches, we show that isotropic reorientation of CMTs and CMFs in aged Col-0 and katanin1-5 ( ktn1-5 ) papilla cells is accompanied by a tendency of pollen tubes to coil around the papillae. We show that this coiled phenotype is associated with specific mechanical properties of the cell walls that provide less resistance to pollen tube growth. Our results reveal an unexpected role for KTN1 in pollen tube guidance on the stigma by ensuring mechanical anisotropy of the papilla cell wall., Competing Interests: LR, FR, CK, SB, JS, IF, TG No competing interests declared, (© 2020, Riglet et al.)

Early events occurring at the surface of the female organ are critical for plant reproduction, especially in species with a dry stigma. After landing on the stigmatic papilla cells, the pollen hydrates and germinates a tube, which penetrates the cell wall and grows towards the ovules to convey the male gametes to the embryo sac. In self-incompatible species within the Brassicaceae, these processes are blocked when the stigma encounters an incompatible pollen. Based on the generation of self-incompatible Arabidopsis lines and by setting up a live imaging system, we showed that control of pollen hydration has a central role in pollen selectivity. The faster the pollen pumps water from the papilla during an initial period of 10 min, the faster it germinates. Furthermore, we found that the self-incompatibility barriers act to block the proper hydration of incompatible pollen and, when hydration is promoted by high humidity, an additional control prevents pollen tube penetration into the stigmatic wall. In papilla cells, actin bundles focalize at the contact site with the compatible pollen but not with the incompatible pollen, raising the possibility that stigmatic cells react to the mechanical pressure applied by the invading growing tube., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology.)