Spatio temporal parameters and symmetry in subjects ascending and descending a ramp, using three different prosthetic feet

This is a post-peer-review, pre-copyedit version of an article published in Journal of Mechanical Science and Technology. The final authenticated version is available online at: https://doi.org/10.1007/s12206-020-0145-

Anterior Cruciate Ligament Injury: Compensation during Gait using Hamstring Muscle Activity

Previous research has shown that an increase in hamstring activation may compensate for anterior tibial transalation (ATT) in patients with anterior cruciate ligament deficient knee (ACLd); however, the effects of this compensation still remain unclear. The goals of this study were to quantify the activation of the hamstring muscles needed to compensate the ATT in ACLd knee during the complete gait cycle and to evaluate the effect of this compensation on quadriceps activation and joint contact forces. A two dimensional model of the knee was used, which included the tibiofemoral and patellofemoral joints, knee ligaments, the medial capsule and two muscles units. Simulations were conducted to determine the ATT in healthy and ACLd knee and the hamstring activation needed to correct the abnormal ATT to normal levels (100% compensation) and to 50% compensation. Then, the quadriceps activation and the joint contact forces were calculated. Results showed that 100% compensation would require hamstring and quadriceps activations larger than their maximum isometric force, and would generate an increment in the peak contact force at the tibiofemoral (115%) and patellofemoral (48%) joint with respect to the healthy knee. On the other hand, 50% compensation would require less force generated by the muscles (less than 0.85 of maximum isometric force) and smaller contact forces (peak tibiofemoral contact force increased 23% and peak patellofemoral contact force decreased 7.5% with respect to the healthy knee). Total compensation of ATT by means of increased hamstring activity is possible; however, partial compensation represents a less deleterious strategy

Minimum toe clearance and tripping probability in people with unilateral transtibial amputation walking on ramps with different prosthetic designs

University of Entre Ríos (UNER) and CONICE

Estadísticos aplicados al estudio de deficiencias del movimiento humano y la rehabilitación

La duración de la rehabilitación luego de la reconstrucción quirúrgica de Ligamento Cruzado Anterior varía entre individuos, resultando indispensable evaluar su progreso en forma personalizada. Estudios previos sugieren como herramienta de evaluación, la cuantificación de la activación muscular (AM) que se obtiene por procesamiento de señales de electromiografía superficial de músculos afectados. El objetivo de este trabajo es cuantificar AM en flexores y extensores de rodilla mediante dos estadísticos: Sample Entropy y Fuzzy Entropy. Se registraron datos de nueve personas sanas y tres pacientes. Los resultados arrojados por los estadísticos propuestos se compararon con los obtenidos mediante Root Mean Square (método convencional). Los tres métodos evidencian una tendencia a restablecer la condición muscular. Los resultados preliminares permiten concluir que SampEn y FuzzyEn brindan información útil para evaluar la evolución de la rehabilitación en los pacientes analizados. Futuros trabajos deberán incluir una población mayor de pacientes para permitir generalizar las conclusiones.Sociedad Argentina de Informática e Investigación Operativ