Development of low-cost and personalized external silicone breast prosthesis produced by additive manufacturing for women who have undergone mastectomy: A pilot study.

BACKGROUND: The aim of this study was to develop a low-cost and personalized method for external breast prosthesis production. METHODS: The projected light method was used for the acquisition of the 3D geometry of the left breast of a healthy 29-year-old woman, 69 kg and 1.69 m. The 3D modeling software Blender was used to make the prosthesis model and mold with adjustments to the model's mesh, such as smoothing, assigning thickness, and creating the walls of the prosthesis mold. Two counter-molds were created. The pieces were manufactured on the 3D printer Stella Lite 3 using polylactic acid filament. Finally, the silicone was pigmented, and the mold was filled. FINDINGS: Prototype 1 of the prosthesis was produced using a mold without a counter-mold, which resulted in a prosthesis of 495 g, considered heavy compared to traditional prostheses for the same breast size. To solve this issue, a counter-mold with pins was used to produce prototype 2 with a mass of 393 g, 20.6% lighter than prototype 1. Prototype 3 was made with a central-volume counter-mold and presented a mass of 355 g, a reduction of 28.3% compared to prototype 1. The definitive breast prosthesis was made with the pin counter-mold with a different silicone. It has nipple and areola pigmentation and a mass of 294 g, 25.2% lighter than prototype 2. INTERPRETATION: The results suggest that the projected light method and additive manufacturing are potential tools for developing external breast prostheses, which may improve the health conditions and quality of life of mastectomized women.

Sports bra but not sports footwear decreases breast movement during walking and running.

Running is a modality that has a large number of adepts, including women. Therefore, it is important to understand how sportswear can help women, with special attention to the breast movement. The aim of this study was to analyse the effect of different combinations of breast support and footwear on the breast movement during walking and running. Twenty women performed treadmill walking (5 km/h) and running (7 and 10 km/h) combining different footwear (barefoot, minimalist, and traditional) and breast support conditions (bare breast, everyday bra, and sports bra). Three-dimensional data from breast and trunk markers were tracked for 10 stride cycles. Relative breast displacement was calculated and derived for velocity. An interaction effect was observed between support, footwear, and speed conditions. The bare breast conditions presented differences from the other conditions in the majority of the kinematic variables, presenting higher breast displacement and velocity values. On the other hand, the sports bra conditions presented the lowest values for the kinematics variables. In the vertical component of breast displacement during running (10 km/h) we verified that the sports bra presented reductions of 56% and 43% in relation to the bare breast and everyday bra conditions, respectively. Despite this, no differences were found between footwear within each breast support condition. A sports bra is efficient to decrease breast movement. In addition, neither of the tested footwear was able to decrease these movements.

Effects of sports bra and footwear on vertebral posture during walking and running.

Little attention has been given to factors which affects women running, such as proper footwear and breast support and their effects on spine. The objective of study was to analyse the influence of different breast support and footwear on vertebral posture during walking and running. Seventeen women (x¯ = 23.51; SD = 3.70 years) performed a treadmill walking (5 km/h) and running (7 and 10 km/h) with different footwear (barefoot, minimalist and traditional) and breast support (bare breast, everyday bra and sports bra) conditions. Spine movements were analyzed using three cameras in grayscale video mode, positioned behind the participant to register reflective markers fixed in the vertebrae. From the 3D coordinates of the trunk markers we computed, for the whole gait cycle (C) and for the average gait posture (neutral curve-NC) the maximal (M) thoracic (T) kyphosis and lateral flexion, and the maximal lumbar (L) lordosis and lateral flexion. Frontal plane: bare breast presented higher lumbar NC than the everyday bra and sports bra, higher MLC than the sports bra and lower MTC than the everyday bra and sports bra. Barefoot presented higher MTC than minimalist. Sagittal plane: bare breast presented lower MTC than the sports bra. Barefoot presented higher lumbar NC than the minimalist and traditional footwear and higher MLC than the minimalist and traditional ones. The sports bra increased curvatures in the thoracic spine that were rectified during bare breast conditions. In addition, both footwears were able to maintain the natural curvatures of the spine in the lumbar.

Effect of visual occlusion and light touch on dynamic postural balance on an unstable platform in elderly and young adult women / Efeito da oclusão visual e do toque suave no equilíbrio postural dinâmico em plataforma instável de idosas e de adultas jovens

ABSTRACT Aging causes the detriment of sensory information that reflects the quality of postural control. The use of light touch has been suggested as a strategy to reduce postural sway even in the absence of vision. However, the effects of this strategy in unstable situations on the support base are unclear. The aim of this study was to analyze the effects of visual occlusion and light touch on the balance of elderly and young adult women on an unstable platform. Twenty elderly women (69.4±6.7 years) and twenty young adult women (20.6±3.2years) performed three attempts at the task which consisted of maintaining balance on an unstable platform on a bipedal base for twenty seconds, with medial-lateral perturbation, in four conditions. The Mann-Whitney U test showed that the elderly women presented worse balance compared to the young adult women in all conditions (p<0.05). The Friedman and Wilcoxon tests demonstrated worse balance with visual occlusion in both groups (p<0.05). On the other hand, there was an improvement in balance using light touch for both vision and no vision conditions (p<0.05). Both groups were able to use the haptic sensory information through light touch to assist in balance maintenance.

RESUMO O envelhecimento causa detrimento nas informações sensoriais que refletem na qualidade do controle postural. O uso do toque suave tem sido sugerido como estratégia para diminuir a oscilação postural mesmo na ausência de visão. Porém, ainda não está claro este efeito em situação de instabilidade da base de suporte. O objetivo do presente estudo foi analisar o efeito da oclusão visual e do toque suave no equilíbrio em plataforma instável de idosas e adultas jovens. Vinte idosas (69,4±6,7 anos) e vinte adultas jovens (20,6±3,2 anos) realizaram três tentativas da tarefa que consistiu em manter o equilíbrio postural dinâmico em plataforma instável, em base bipodal durante vinte segundos, com perturbação médio-lateral em 4 condições. O teste de Mann-Whitney U demonstrou que as idosas apresentaram pior desempenho no equilíbrio em comparação às adultas jovens em todas as condições (p<0,05). Os testes de Friedman e Wilcoxon demonstraram pior desempenho no equilíbrio com a oclusão visual em ambos os grupos (p<0,05). Por outro lado, houve melhora no equilíbrio com o toque tanto na condição com visão quanto sem visão (p<0,05). Ambos os grupos foram capazes de utilizar as informações sensoriais hápticas por meio do toque suave para auxiliar na manutenção do equilíbrio.