[en] Spinal-cord-injured (SCI) subjects with some level of hip actuation but with no or very weak actuation at knee and ankle levels can often walk with the assistance of knee-ankle-foot orthoses (KAFO) and crutches. However, since knees are kept extended at all times, even during the swing phase, gait becomes very uncomfortable as the hip must be raised for the swing, thus leading to a high energetic cost which makes fatigue appear quickly. Moreover, the use of crutches leads to high loads in some joints, particularly shoulders, which may produce injuries in the long term. The result is that many patients prefer to use the wheelchair, thus losing the bene ts of walking for rehabilitation and for their general health state. To alleviate these problems, active orthoses have been proposed that detect swing intention and launch a knee exion-extension cycle, thus approaching healthy gait, which can make gait more comfortable and increase the actual chances of walking for users. Some magnitudes, as joint reactions or energetic cost, may serve as indicators to evaluate the e ect of assistive devices in a speci c user and, hence, the likeliness of their actual use in the long term. The combined use of motion-force-EMG capture and personalized neuromusculoskeletal models enables to estimate the mentioned magnitudes, without the need for long and tiring experimental tests which could hardly be undergone by these subjects. Therefore, the present work is devoted, on the one hand, to review, select, adapt, improve and/or develop, and validate, all the necessary methods and tools which are required for this purpose: (i) personalized musculoskeletal models; (ii) methods for analysis at skeletal and musculoskeletal levels; (iii) methods for energetic cost estimation. And, on the other hand, to apply them to two SCI subjects, bilateral and unilateral, respectively, and to compare a new active KAFO with a conventional passive one. Results show that the evaluation of device impact through the mentioned indicators is e ective, and that the new active system objectively streamlines walking to users.

[gl] Os lesionados medulares con algunha capacidade de actuación en cadeira pero con pouca ou nula capacidade de actuación en xeonllo e nocello, poden en moitos casos cami~nar coa axuda de orteses de xeonllo-nocello-p e e muletas. Con todo, dado que os xeonllos se mante~nen estendidos en todo momento, mesmo durante a fase de abalo, a marcha resulta moi inc omoda, pois a cadeira debe levantarse para permitir o abalo da perna, o que sup on un alto custo enerx etico que fai aparecer a fatiga rapidamente. Ademais, o uso de muletas produce cargas elevadas nalgunhas articulaci ons, especialmente nos ombreiros, o que pode xerar lesi ons a longo prazo. O resultado e que moitos pacientes pre ren usar a cadeira de rodas, perdendo as os bene cios de cami~nar para a s ua rehabilitaci on e para o seu estado de sa ude xeral. Para paliar estes problemas, propux eronse orteses activas que detectan a intenci on de dar o paso e lanzan un ciclo de exi on-extensi on de xeonllo, aproximando as a marcha normal, o que pode facer a marcha m ais c omoda e aumentar as posibilidades reais de cami~nar para os usuarios. Algunhas magnitudes, como as reacci ons nas articulaci ons ou o custo enerx etico, poden servir como indicadores para avaliar o efecto dos dispositivos de asistencia nun usuario espec co e, polo tanto, a probabilidade do seu uso real a longo prazo. O uso combinado da captura de movemento-forza-EMG e os modelos neuromusculoesquel eticos personalizados permite estimar as magnitudes mencionadas, sen a necesidade de longas e esgotadoras probas experimentais que di cilmente poder an afrontar estes pacientes. Polo tanto, o presente traballo est a dedicado, por unha banda, a revisar, seleccionar, adaptar, mellorar e/ou desenvolver, e validar, todos os m etodos e ferramentas necesarios que se requiren para este prop osito: (i) modelos m usculoesquel eticos personalizados; (ii) m etodos de an alises a nivel esquel etico e musculoesquel etico; (iii) m etodos de estimaci on de custo enerx etico. E, doutra banda, a aplicalos a dous lesionados medulares, bilateral e unilateral, respectivamente, e a comparar unha nova ortese activa cunha pasiva convencional. Os resultados mostran que a avaliaci on do impacto do dispositivo a trav es dos indicadores mencionados e efectiva, e que o novo sistema activo facilita certamente cami~nar aos usuarios.