Introducción La úlcera de pie diabético (UPD) es una complicación clínica de la diabetes mellitus (DM). Se ha sugerido que la anemia podría asociarse a su progresión. El objetivo de nuestro estudio fue evaluar la asociación entre anemia y los desenlaces clínicos adversos de la UPD en pacientes hospitalizados. Métodos Llevamos a cabo un análisis secundario de base de datos de dos estudios de cohorte retrospectivo de pacientes con UPD hospitalizados en un hospital público de referencia nacional en Lima durante el año 2015 y 2019. La anemia definida según el valor de hemoglobina de ingreso fue nuestra variable de exposición. Para nuestra variable resultado, agrupamos la falla en la cicatrización y la amputación, en la variable “desenlace clínico adverso”. Estimamos riesgos relativos crudos (RR) y ajustados (RRa) con intervalos de confianza al 95% (IC95%) mediante modelos lineales generalizados de familia Poisson con Bootstrap no paramétrico con sesgo corregido y acelerado. Resultados Incluimos 160 pacientes cuya media de edad fue 58 ± 12,7 años. Detectamos anemia en 102 (63,8%) pacientes, 111 (69,4%) presentaron el desenlace clínico adverso, 49 (44,1%) fueron amputados, y 62 (55,9%) pacientes presentaron una úlcera que no cicatrizó. La anemia se asoció significativamente con el desenlace compuesto (RRa = 1,37: IC95% = 1,05 - 1,80; p=0,019) y la amputación (RRa = 1,78: IC95% = 1,12 - 3,28; p=0,017). No encontramos evidencia estadística de asociación significativa entre la anemia y la falla en la cicatrización de la UPD (RRa = 1,43: IC95% = 0,96 - 2,12; p=0,072). Conclusión La anemia incrementó el riesgo de presentar un desenlace clínico adverso y de la amputación en pacientes hospitalizados con UPD. / Background Diabetic foot ulcer (DFU) is a clinical complication of diabetes mellitus (DM). Anemia has been associated with the progression of this disease. The objective of our study was to evaluate the association between anemia and adverse clinical outcomes of DFU in hospitalized patients. Methods We carried out a secondary database analysis from two retrospective cohort studies of DFU patients hospitalized in a national reference public hospital in Lima during 2015 and 2019. The exposure variable was anemia defined according to the hemoglobin value at admission. For our outcome variable, we grouped non-healing ulcers and amputation into the “adverse clinical outcome”. We estimated crude (RR) and adjusted relative risks (aRR) with 95% confidence intervals (CI95%) using generalized linear Poisson family models with accelerated and bias-corrected non-parametric bootstrap. Results We included 160 patients, which average age was 58 ± 12.7 years. Anemia was detected in 102 (63.8%) patients, 111 patients (69.4%) had an adverse clinical outcome, 49 patients (44.1%) were amputated, and 62 patients (55.9%) had non-healing ulcers. Anemia was significantly associated with the composite outcome (aRR = 1,37: CI95% = 1,05 - 1,80; p=0,019) and amputation (aRR = 1,78: CI95% = 1,12 - 3,28; p=0,017). We found no statistical evidence of a significant association between anemia and non-healing ulcers (aRR = 1,43: CI95% = 0,96 - 2,12; p=0,072). Conclusions Anemia increases the risk of amputation and adverse clinical outcome in hospitalized patients with DFU. / Tesis

Pertinence. Les névromes entraînent souvent des douleurs neuropathiques (DN) au membre résiduel (MR) chez les personnes amputées. Objectifs. (1) décrire la fréquence et la localisation des névromes avec l'imagerie musculosquelettique par ultrasonographie (IMU); (2) caractériser les névromes avec des biomarqueurs géométriques, de luminosité, de texture et d’hyperémie à l’IMU ; (3) déterminer l'association entre la DN et des mesures de résultats sociodémographiques, prothétiques, fonctionnels et de participation, et (4) évaluer l'association entre la DN, les biomarqueurs et la symptomatologie à la compression du névrome. Méthode. Vingt-trois participants avec amputations transtibiales ont complété des questionnaires avant d’être évalués par IMU. Des images des névromes ont été enregistrées et des biomarqueurs calculés. Résultats. La prévalence des névromes est 1,3/MR et ceux-ci touchent tous les nerfs sectionnés, avec une prédominance au nerf fibulaire superficiel (42%). Ils sont significativement plus épais (+247 %), plus hypoéchogènes (-19,31 %) et plus homogènes (+29,71 %) que le nerf proximal. Les névromes du nerf tibial présentent la plus grande aire transversale (CSA) (75,19 mm2). Une durée de port prothétique moindre, une incapacité fonctionnelle plus élevée et une douleur provoquée à la compression d’un névrome situé sur le nerf fibulaire superficiel sont positivement associés à la DN. Aucune association n’a été établie entre la CSA, le ratio d’épaisseur, l’épaisseur des tissus sus-jacents et la DN. Conclusion. Caractériser les névromes des MR avec des biomarqueurs à l’IMU pourrait devenir utile en clinique et en recherche. La validité prédictive des biomarqueurs en lien avec la douleur neuropathique reste à clarifier. / Relevance. The presence of neuromas often leads to neuropathic residual limb (RL) pain in individuals with amputation. Objectives. (1) depict the frequency and localization of neuromas using musculoskeletal ultrasound imaging (MSKUS) in RL; (2) characterize neuromas using geometric, luminosity, texture, and hyperemia MSKUS biomarkers; (3) determine the association between neuropathic RL pain and socio-demographic, prosthetic, functional, and participation outcome measures, and (4) assess the association between neuropathic RL pain, MSKUS biomarkers and symptomatology upon neuroma compression. Methods. 23 participants with transtibial amputations completed pain, function, and participation questionnaires before undergoing an MSKUS imaging assessment. Images of the neuromas in the longitudinal and transverse planes were recorded before computing MSKUS biomarkers. Results. There was a prevalence of 1.3 neuromas per RL. All sectioned peripheral nerves could be affected, with a predominance for the superficial fibular nerve (42% of all cases). Overall, neuromas were significantly thicker (thickness= +247%), darker (echogenicity= -19.31%) and smoother (homogeneity= +29.71%) than their proximal nerve’s portion. The largest neuroma cross-sectional area (CSA) appeared on the tibial nerve (75.19 mm2). Less daily prosthesis wearing time, higher disability, and eliciting pain upon compression of a neuroma on the superficial fibular nerve were positively associated to RL neuropathic pain intensity. No association was established between the CSA, thickness ratio, thickness of the overlying soft tissues and neuropathic RL pain. Conclusion. Characterizing neuromas using MSKUS biomarkers may become valuable in clinical practice and research protocols. The predictive validity of such biomarkers with regards to neuropathic pain remains to be clarified.

No description available.

Background: The number of people with diabetes is rising globally, and they are at higher risk of foot complications that can ultimately result in lower limb amputation. Additionally, individuals with diabetes whoundergo amputation are more likely to lose the contralateral limb. Consistent care and preventive measuresare crucial for reducing the risk of further amputations. Aim: This study aims to explore the current experience of certified prosthetist and orthotist in Denmarkconcerning the assessment of the contralateral limb in individuals with diabetes who utilize a lower limbprosthesis. Method: A qualitative study with an exploratory research design was conducted. Thematic analysis, using aninductive approach was employed to analyze data from eight semi-structured interviews with CPOs from Denmark. Findings: The analysis of the interview results revealed three main themes - responsibility, prioritization,and barriers - which frequently overlap. Each theme had multiple sub-themes which highlights the variationin the participants’ experiences. Conclusion: The variation in responses gathered from the interviews unveiled diverse perspectives on responsibility, prioritization, and barriers which points to a lack of clear guidelines in the Danish healthcaresystem regarding this assessment of the contralateral limb in this patient group. This study offers novel insightsinto the diverse experiences and decision-making processes of Danish CPOs when it comes to the contralaterallimb assessment in diabetic foot care. / <p></p><p></p>

Ce travail explore des solutions afin d'améliorer la reconnaissance des gestes de la main à l'aide de signaux électromyographiques. Grâce aux prothèses myoélectriques, cette technologie a le potentiel de transformer la vie des amputés des membres supérieurs. Malheureusement, les prothèses myoélectriques disponibles sur le marché peinent à reproduire fidèlement les gestes de la main, car il est complexe de déduire l'intention de l'utilisateur à partir de l'activité musculaire mesurée, particulièrement entre différentes utilisations de la prothèse. Pour adresser ce problème, ce travail présente une solution logicielle permettant, à l'aide d'un nouveau capteur flexible d'électromyographie haute densité (HD-EMG) à 64 électrodes, de renforcer la robustesse de la détection contre différentes sources de variations. Cette innovation repose sur l'introduction d'une approche d'augmentation des données par décalage circulaire (ABSDA) couplée à un réseau de neurones à convolution (CNN) et une version anticrénelée (AA-CNN) permettant d'améliorer la robustesse de la classification au mouvement des électrodes et à la variabilité entre les séances. La méthode ABSDA-CNN proposée améliore significativement la précision de la reconnaissance des gestes. Ce travail examine également le potentiel de l'apprentissage machine sur graphes, un domaine émergent qui applique la théorie des graphes à l'intelligence artificielle. En utilisant cette approche pour représenter les capteurs HD-EMG sous forme de graphes, il est possible de capitaliser sur leur structure géométrique naturelle afin de construire des réseaux de neurones sur graphes (GNN) novateurs qui surpassent les réseaux à convolution traditionnels. L'introduction de ces nouvelles architectures permet d'explorer la notion d'invariance en translation des réseaux de neurones en démontrant l'importance d'apprendre la position des électrodes pour améliorer la précision de la reconnaissance des gestes Finalement, une plateforme embarquée sans fil est introduite pour réaliser de la reconnaissance de gestes en temps réel, grâce à un accélérateur Coral Tensor Processing Unit (TPU). Cette solution permet d'intégrer l'intelligence artificielle directement dans les prothèses, supprimant la dépendance à des équipements externes coûteux. Pour une meilleure flexibilité, le système propose la calibration des modèles d'inférence localement ou à distance par le biais d'un serveur. L'exploration des techniques de quantification des données à 8 bits démontre que la compatibilité matérielle peut être obtenue sans sacrifier les performances. / This work explores solutions to improve hand gesture recognition using electromyographic signals. Thanks to myoelectric prostheses, this technology has the potential to radically transform the lives of upper limb amputees. Unfortunately, the myoelectric prostheses currently available on the market struggle to faithfully reproduce hand gestures because it is complex to correctly infer the user's intention from the measured muscle activity, especially between different uses of the prosthesis. To address this problem, this work presents a software solution that, with the help of a new flexible high-density electromyography (HD-EMG) sensor with 64 electrodes, enhances the robustness of detection against various sources of variations. This innovation is based on the introduction of an array barrel-shifting data augmentation (ABSDA) coupled with a convolutional neural network (CNN) and an anti-aliased version (AA-CNN) to improve robustness to electrode movement, forearm orientation, and inter-session variability. The proposed ABSDA-CNN method significantly improves the accuracy of gesture recognition. This work also examines the potential of graph machine learning, an emerging field that applies graph theory to artificial intelligence. By using this approach to represent HD-EMG sensors as graphs, it is possible to capitalize on their natural geometric structure to construct innovative graph neural networks (GNNs) that surpass traditional convolutional networks. The introduction of these new architectures allows for the exploration of the notion of invariance to translation of neural networks by demonstrating the importance of learning electrode positions to improve gesture recognition accuracy. Finally, a wireless embedded platform is introduced for real-time gesture recognition, thanks to a Coral Tensor Processing Unit (TPU) accelerator. This solution enables the integration of artificial intelligence directly into prostheses, eliminating the dependency on expensive external hardware. For enhanced flexibility, the system offers model calibration locally or remotely via a server. Exploring 8-bit data quantization techniques shows that hardware compatibility can be achieved without sacrificing performance.

Although dynamic prosthetic alignment is an important process for the rehabilitation of transtibial amputees, such alignment technique is subjective and inconsistent. Using biomechanical variables and questionnaire assessments, this study compared an instrument-assisted dynamic alignment technique using the Compas™ system and conventional alignment techniques on nine adults with unilateral transtibial amputation. A focus group discussion was conducted with six prosthetists to understand clinical practice of dynamic alignment and their perception of the Compas™ system. Results found that Compas™ produced more anterior weight line displacement and greater varus moment on the prosthesis than conventional alignment techniques. Alignment changes did not affect pelvic acceleration, and the instrument-assisted alignment technique produced certain biomechanical changes but not necessarily better alignments. Although the current version of the Compas™ system is not clinically feasible, it can be used as a teaching/justification tool. Further investigation with larger sample size and ankle alignment or moment measures is needed.

Although dynamic prosthetic alignment is an important process for the rehabilitation of transtibial amputees, such alignment technique is subjective and inconsistent. Using biomechanical variables and questionnaire assessments, this study compared an instrument-assisted dynamic alignment technique using the Compas™ system and conventional alignment techniques on nine adults with unilateral transtibial amputation. A focus group discussion was conducted with six prosthetists to understand clinical practice of dynamic alignment and their perception of the Compas™ system. Results found that Compas™ produced more anterior weight line displacement and greater varus moment on the prosthesis than conventional alignment techniques. Alignment changes did not affect pelvic acceleration, and the instrument-assisted alignment technique produced certain biomechanical changes but not necessarily better alignments. Although the current version of the Compas™ system is not clinically feasible, it can be used as a teaching/justification tool. Further investigation with larger sample size and ankle alignment or moment measures is needed.

The invention of the vaccine has been one of the greatest public health triumphs of the modern world. Each new vaccine has saved thousands - even millions - of lives worldwide, but this success has been fraught with controversy over the safety and even the effectiveness of vaccines. Vaccines have not always had a spotless safety record, but today’s vaccines are incredibly safe and continue to protect millions of people against diseases that have significantly declined or nearly disappeared from the developing world. It is this very success that has led many people to forget, or never discover, what those diseases are and how destructive they can be. This report tells the story of several families whose lives were deeply affected by vaccine-preventable diseases, accompanied with images that help tell their story. Following these stories is a broader discussion of the issues related to vaccines, the misunderstandings and misinformation that often circulate about them, a brief mention of their safety and efficacy, and a general discussion of many of the diseases they can prevent. / text

Scar-free wound healing and regeneration are uncommon phenomena permitting the near complete restoration of damaged tissues, organs and structures. Although rare in mammals, many lizards are able to undergo scarless healing and regeneration following loss of the tail. This study investigated the spontaneous and intrinsic capacity of the leopard gecko (Eublepharis macularius) tail to undergo scar-free wound healing and regeneration following two different forms of tail loss: autotomy, a voluntary and evolved mechanism of tail shedding at fracture planes; and surgical amputation, involuntary loss of the tail outside the fracture planes. Furthermore, I investigated the ability of the regenerate tail to regenerate by amputating a regenerate tail (previously lost by autotomy). To investigate these phenomena I imaged wound healing and regenereating tails daily (following autotomy and amputation) to document gross morphological changes. I used histochemistry to document tissue structure and immunohistochemistry to determine the tissue/cellular location of my five proteins of interest (PCNA, MMP-9, WE6, α-sma, TGF-β3). Each of these proteins of interest has been previously documented during wound healing and/or regeneration in other wound healing/regeneration model organisms (e.g. mice, urodeles, lizards, zebrafish). Scar-free wound healing and regeneration occurred following autotomy, amputation of the original tail and amputation of the regenerate tail, indicating that the leopard gecko tail has an instrinsic scar-free wound healing and regenerative capacity that is independent of the mode of tail loss (autotomy or amputation). Furthermore immunohistochemistry revealed a conserved sequence and location of the expression of the five proteins of interest following both forms of tail loss. These results provide the basis for further studies investigating scar-free wound healing and regeneration in a novel amniote model, the leopard gecko. / NSERC

L’objectif de ce travail de thèse est de caractériser, chez les amputés unilatéraux du membre inférieur, les modalités posturales qui interviennent dans la régulation de l’équilibre orthostatique et d’étudier l’impact de l’amputation sur la production de force à la cheville physiologique. Une première étude a révélé la présence de trois modalités posturales afin de réguler le contrôle postural : les amputés transfémoraux adoptent une modalité posturale basée sur les paramètres de stabilité, les amputés transtibiaux optent pour une modalité posturale mixte et les non amputés se réfèrent aux paramètres de l’attitude posturale. Etant donné que l’articulation de la cheville joue un rôle essentiel dans la régulation de l’équilibre postural, il était alors pertinent d’investiguer la production de force à la cheville physiologique. Toutefois, les ergomètres permettant d’étudier l’articulation de la cheville présentent des biais de mesure majeurs. Dans ce cadre, une deuxième étude a été menée afin de développer et valider un nouvel ergomètre pour cheville : le B.O.T.T.E. Parallèlement, la mise en place d’une méthode de mesure basée sur le retour visuel permettant une quantification fiable du couple de force a fait l’objet d’une troisième étude. Ensuite, une quatrième étude visait à utiliser le B.O.T.T.E. pour investiguer l’impact de l’amputation sur la production de force à la cheville physiologique. Les résultats de cette étude confirment la présence d’un déficit au niveau du couple de force généré en flexion plantaire (conditions maximale et sous maximale) chez les amputés transfémoraux. Enfin, ce travail de thèse vise à aider les rééducateurs et les cliniciens à optimiser la prise en charge des patients amputés. / This Ph.D. thesis aims to evaluate the standing posture modalities and the ankle joint torque in the intact limb in unilateral lower limb amputees. A first study shows the presence of three posture modalities: the non-amputee group relied on standing erect, the transfemoral amputees’ stance depended on balance control and the transtibial amputees exhibited a mixed modality of simultaneously maintaining an upright stance and standing balance. Since the ankle muscles have a functional importance in standing posture modalities, it is imperative to investigate the ankle joint torque in the intact limb. However, the current devices used to assess the ankle joint present substantial limitations for the measurement. Thus, a second study was designed to develop and to validate a new ankle ergometer B.O.T.T.E. Moreover, a third study was achieved in order to estimate the effect of visual feedback on enhancing isometric maximal voluntary contractions. A fourth study was realized to investigate the ankle joint torque in the intact leg of unilateral lower limb amputees. The results show that transfemoral amputees produce less torque and are less steady compared to transtibial amputees and able-bodied individuals. Overall, the present findings of this Ph.D. thesis could have implications for clinical practice and for rehabilitation of patients with a lower limb amputation.