Structural assessment of pre-flexion in silicone implants for arthroplasty of the first metatarsophalangeal joint.

The development of numerical models to analyze pathologies and implants related to the first metatarsophalangeal joint of the foot remains an issue for attention. The structural effects of implants pre-flexion have been discarded in several finite elements analyses due to complexities to achieve these positions. This work aims to evaluate if the pre-flexion stress state should be included or could be discarded when only flexion is applied in two different silicone commercial implants, Swanson and Tornier, during a gait cycle. Finite element models were created for silicone implants. Both models were discretized using high-order finite elements. The hyperelasticity constitutive material model of Arruda-Boyce was used, based on experimental data; its behavior was compared with linear elastic models reported and used frequently assuming small and large deformations and applying to the Swanson and Tornier implants a flexion angle of 64°, which corresponds to in vivo measurements reported after implantation. Comparison between models, regarding hyperelastic model, showed mean variations of up to 32.5% for stresses and 14.01% for bending moment in Swanson implant, while for Tornier implant mean variations of 29.73% and 632.55% was obtained for stress and bending moment respectively. The maximum stress value obtained for the hyperelastic model in the Swanson implant reached a value of 22.82% of the tensile strength of the implant material while in the Tornier implant reached a value of 25.92%, the above values were evaluated at a flexion angle of 64°. The results suggest considering in finite element analyses not only the stress state generated to achieve critical flexion position in pleflexed implants models but also the hyperelastic material behavior of silicone for implants to avoid dismissing the non-linear structural behavior of hyperelastic materials.

Heel Height as an Etiology of Hallux Abductus Valgus Development: An electromagnetic Static and Dynamic First Metatarsophalangeal Joint Study.

Background: Hallux abductus valgus (HAV) is a forefoot condition produced by extrinsic and intrinsic factors. Shoes with a high heel height and a typical narrow tip toe box can induce deviations in both the proximal phalanx of the hallux (PPH) and the first metatarsal (IMTT) bones. Nevertheless, the isolated role of heel height remains unclear in the development of HAV pathology. Objectives: The goal was to determine if the heel height increase of shoes without a narrow box toe could augment the PPH and IMTT deviation in frontal, sagittal, and transverse planes toward the first metatarsophalangeal joint (MPJ) and the first metatarsocuneiform joint (MCJ), respectively, during static and dynamic conditions in relation to precursor movements of HAV. Methods: Women with an average age of 25.10 ± 4.67 years were recruited in this cross-sectional study to assess the three planes of motion of PPH and IMTT while wearing high heels with heights at 3, 6, 9 cm and unshod conditions via sandals. The measurements used an electromagnetic goniometer device with sensors placed on medial aspects of the PPH and IMTT bones under static and dynamic conditions. Results: Wearing shoes with a 6 cm heel in dynamic condition may increase the PPH valgus and abduction deviation from 3.15 ± 0.10° to 3.46 ± 0.05° (p < 0.05) and from 1.35 ± 0.28° to 1.69 ± 0.30° (p < 0.001), respectively. In addition, a PPH abduction increase from 1.01 ± 0.36° to 1.31 ± 0.46° (p < 0.05) after wearing shoes with a 6 cm heel height was observed under static conditions. Conclusions: Wearing shoes with a heel height of 6 cm without a narrow box toe interference may produce PPH abduction and valgus deviations related to HAV formation.

Impact of shoe size in a sample of elderly individuals.

INTRODUCTION:: The use of an improper shoe size is common in older people and is believed to have a detrimental effect on the quality of life related to foot health. The objective is to describe and compare, in a sample of participants, the impact of shoes that fit properly or improperly, as well as analyze the scores related to foot health and health overall. METHOD:: A sample of 64 participants, with a mean age of 75.3±7.9 years, attended an outpatient center where self-report data was recorded, the measurements of the size of the feet and footwear were determined and the scores compared between the group that wears the correct size of shoes and another group of individuals who do not wear the correct size of shoes, using the Spanish version of the Foot Health Status Questionnaire. RESULTS:: The group wearing an improper shoe size showed poorer quality of life regarding overall health and specifically foot health. Differences between groups were evaluated using a t-test for independent samples resulting statistically significant (p<0.05) for the dimension of pain, function, footwear, overall foot health, and social function. CONCLUSION:: Inadequate shoe size has a significant negative impact on quality of life related to foot health. The degree of negative impact seems to be associated with age, sex, and body mass index (BMI).

Impact of shoe size in a sample of elderly individuals / Impacto do tamanho do calçado em uma amostra de idosos

Summary Introduction: The use of an improper shoe size is common in older people and is believed to have a detrimental effect on the quality of life related to foot health. The objective is to describe and compare, in a sample of participants, the impact of shoes that fit properly or improperly, as well as analyze the scores related to foot health and health overall. Method: A sample of 64 participants, with a mean age of 75.3±7.9 years, attended an outpatient center where self-report data was recorded, the measurements of the size of the feet and footwear were determined and the scores compared between the group that wears the correct size of shoes and another group of individuals who do not wear the correct size of shoes, using the Spanish version of the Foot Health Status Questionnaire. Results: The group wearing an improper shoe size showed poorer quality of life regarding overall health and specifically foot health. Differences between groups were evaluated using a t-test for independent samples resulting statistically significant (p<0.05) for the dimension of pain, function, footwear, overall foot health, and social function. Conclusion: Inadequate shoe size has a significant negative impact on quality of life related to foot health. The degree of negative impact seems to be associated with age, sex, and body mass index (BMI).

Resumo Introdução: o uso de sapatos com tamanhos inadequados é comum em pessoas idosas e acredita-se resultar em efeito negativo sobre a qualidade de vida relacionada à saúde do pé. O objetivo é descrever e comparar o impacto de uma amostra de participantes usando calçados de tamanho adequado e indivíduos com calçados de tamanho inadequado, e as pontuações relacionadas com a saúde do pé e geral. Método: de uma amostra de 64 participantes, com idade média de 75,3±7,9, de um centro ambulatorial, dados de autorrelato foram registrados e medidas do tamanho dos pés e dos calçados foram determinadas. Os escores foram comparados pelo Foot Health Status Questionnaire, na versão em espanhol, entre os grupos que usavam sapatos de tamanhos corretos e incorretos. Resultados: o grupo que utilizava sapatos inadequados mostrou pior qualidade de vida relacionada à saúde geral e no pé. Diferenças entre os grupos foram avaliadas utilizando o teste t para amostras independentes, sendo estatisticamente significativas (p<0,05) para dimensão da dor, função, calçados, saúde geral, do pé e função social. Conclusão: o uso de calçado inadequado tem um impacto negativo significativo sobre a qualidade de vida relacionada à saúde do pé. O grau de impacto negativo parece estar associado com idade, sexo e índice de massa corpórea (IMC).

Papel de la abuela en la lactancia materna / The Grandmother's Role in Breastfeeding / O papel da avó na lactância materna

Objetivo: investigar la influencia de la abuela sobre la madre que da lactancia materna y su relación con la incidencia y prevalencia de la misma. Método: se realizó una revisión integral consultando de las bases de datos MEDLINE OVID, DIALNET y COCHRANEC LIBRARY. Tras el análisis de los textos, se escogieron once estudios de investigación que iban dirigidos directamente a comprobar la influencia de las abuelas en la incidencia y prevalencia de la lactancia materna en diferentes contextos. Resultados: la abuela apareció como fuente de apoyo en población rural (41%). En población urbana la abuela aparece entre los tres factores principales (intención de la madre de lactar o no, decisión de la madre del patrón de alimentación de su hijo e información objetiva sobre pautas de amamantamiento), tanto en el papel de apoyo (94,7%), como en el de obstáculo (26,7%). En cuanto a la decisión de la madre sobre el patrón de alimentación de sus hijos, el 78% refiere haber tomado la decisión antes del embarazo o en el primer trimestre. La convivencia con la abuela tuvo asociación positiva con dar agua o infusiones (PR regresión de Cox con IC 95%: 1,51 [1,10-2,09]; p = 0,011). Conclusiones: a la luz de la revisión, la influencia detractora o no que ejerce la abuela sobre la lactancia materna la da sobre los tres factores principales. La influencia detractora ejercida por los consejos de la abuela parece estar relacionada con conocimientos erróneos adquiridos como "generación del biberón" más que con la intencionalidad, y es susceptible de modificarse con información adecuada, con resultados favorables sobre el patrón de alimentación.

Objective: to investigate the effect the grandmother has on the breastfeeding mother and how it relates to the incidence and prevalence of breastfeeding. Materials and methods: A comprehensive database review was conducted in MEDLINE OVID, DIALNET and the COCHRANE LIBRARY. After analyzing the texts, eleven studies aimed directly at verifying the influence of grandmothers on the incidence and prevalence of breastfeeding in different contexts were selected. Results: The grandmother emerges as a source of support among the rural population (41%). In the urban population, the grandmother appears among the three main factors (mother's intention to breastfeed or not, mother's decision on a feeding pattern for her child, and objective information on breastfeeding patterns), in a supprting role (94, 7%) and in a hindering role (26.7%). As for the mother's decision on a feeding pattern for her children, 78% reported having made the decision before pregnancy or in the first quarter. Living with the grandmother is positively associated with providing water or teas (PR in Cox regression with 95% CI: 1.51 [1.10 to 2.09], p = 0.011). Conclusions: In the light of the review, the detracting or non-detracting influence exerted by the grandmother with respect to breastfeeding affects the three main factors. The detracting influence exerted by the grandmother's advice seems to be related to incorrect knowledge acquired more as part of the "bottle fed generation" rather than intentionality, and is susceptible to being modified through appropriate information, with favorable results on the feeding pattern.

Objetivo: pesquisar a influência da avó sobre a mãe que dá lactancia materna e sua relação com a incidência e prevalência desta. Materiais e métodos: realizou-se uma revisão integral consultando as bases de dados MEDLINE OVID, DIALNET e COCHRANE LIBRARY. Após a análise dos textos, escolheram-se onze estudos de pesquisa que vão dirigidos diretamente a comprovar a influência das avós na incidência e prevalência da lactancia materna em diferentes contextos. Resultados: constatou-se que a avó apareceu como fonte de apoio na população rural (41%). Na população urbana, a avó aparece entre os três fatores principais (intenção da mãe de lactar ou não, decisão da mãe do padrão de alimentação de seu filho e informação objetiva sobre pautas de amamentação), tanto no papel de apoio (94,7%) quanto no de obstáculo (26,7%). Quanto à decisão da mãe sobre o padrão de alimentação de seus filhos, 78% referem ter tomado a decisão antes da gravidez ou no primeiro trimestre. A convivência com a avó teve associação positiva com dar água ou infusões (PR regressão de Cox com IC 95%: 1,51 [1,10-2,09]; p = 0,011). Conclusões: à luz da revisão, a influência detratora ou não que exerce a avó sobre a lactancia materna se dá sobre os três fatores principais. A influência detratora exercida pelos conselhos avó parece estar mais relacionada com conhecimentos errôneos adquiridos como "geração da mamadeira" do que com a intencionalidade e é suscetível de ser modificado com informação adequada, com resultados favoráveis sobre o padrão de alimentação.