Background: The aim of the present study was to evaluate the relationship between tibial slope angle and ligament strain during in vitro landing simulations that induce ACL failure through the application of variable external loading at the knee. The hypothesis tested was that steeper posterior tibial slope angle would be associated with higher ACL strain during a simulated landing task across all external loading conditions. Methods: Kinetics previously derived from an in vivo cohort performing drop landings were reproduced on 45 cadaveric knees via the mechanical impact simulator. MRIs were taken of each specimen and used to calculate medial compartment posterior tibial slope, lateral compartment posterior tibial slope, and coronal plane tibial slope. Linear regression analyses were performed between these angles and ACL strain to determine whether tibial slope was a predictive factor for ACL strain. Findings: Medial and lateral posterior tibial slope were predictive factors for ACL strain during some landings with higher combined loads. Medial posterior slope was more predictive of ACL strain in most landings for male specimens, while lateral posterior and coronal slope were more predictive in female specimens, but primarily when high abduction moments were applied. Interpretation: Tibial slope has the potential to influence ACL strain during landing, especially when large abduction moments are present at the knee. Deleterious external loads to the ACL increase the correlation between tibial slope and ACL strain, which indicates that tibial slope angles are an additive factor for athletes apt to generate large out-of-plane knee moments during landing tasks.

Background Significant effort has gone into the identification and quantification of the underlying mechanisms of primary ACL injury. Secondary ACL injury is observed in approximately 1/4 to 1/3 of athletes who return to sport following ACL reconstruction. However, little has been done to evaluate the mechanisms and playing circumstances surrounding these repeat injuries. Hypothesis/Purpose The purpose of this study was to characterize the mechanisms of non-contact secondary ACL injuries using video analysis. It was hypothesized that in video recordings of secondary ACL injury, athletes would exhibit greater frontal plane hip and knee angles, but not greater hip and knee flexion, at 66 ms following initial contact (IC) as compared to at IC and 33ms following IC. Study Design Cross-Sectional Study Methods Twenty-six video recordings of competitive athletes experiencing secondary ACL ruptures via noncontact mechanisms were analyzed for lower extremity joint kinematics, playing situation, and player attention. Kinematics were assessed at IC as well as 33 ms (1 broadcast frame) and 66 ms (2 broadcast frames) following IC. Results Knee flexion and knee frontal plane angles were greater at 66 ms than IC (p ≤ 0.03). Hip, trunk, and ankle frontal plane angles were not greater at 66 ms than IC (p ≥ 0.22). Injuries were distributed between attacking play (n=14) and defending (n=8). Player attention was most commonly focused on the ball (n=12) or an opponent (n=7). A single-leg landing accounted for just over half of the injuries (54%), while a cutting motion accounted for the remainder of the injuries (46%). Conclusion Secondary ACL injury was most likely to occur during landing or a sidestep cut with player attention external to their own body. Knee valgus collapse combined with limited hip motion was identified in the majority of secondary injuries. Level of Evidence Level IIIb

Existen diferentes causas para la amputación de uno o ambos miembros inferiores. En países en desarrollo la atención en salud es de difícil acceso y en muchos casos la rehabilitación de estas personas no es adecuada, ni en el momento oportuno, lo que implica que la situación de estas personas empeore. En Colombia, la cantidad de personas amputadas por el conflicto armado refleja una grave situación para los derechos humanos. Las heridas causadas por las minas antipersonales son complejas y catastróficas, causan, en su mayoría, una amputación. Las personas en situación de discapacidad víctimas del conflicto armado, encuentran barreras para desempeñar los mismos roles que desempeñaban antes de adquirir la discapacidad, en estos casos, los procesos de rehabilitación juegan un papel importante y casi trascendental en la vida de la persona, ya que permiten la potenciación de sus capacidades y habilidades. Con el fin de brindar soluciones a limitaciones de mercado y espacio para la rehabilitación se propone SensRehApp la cual a través de una unidad de medición inercial detecta movimientos de la persona y los envía a un computador que le permita hacer diferentes ejercicios para cada una de las etapas del proceso de rehabilitación. Estos ejercicios fueron determinados junto a personal médico y teniendo como base la Guía de Práctica Clínica para el diagnóstico y tratamiento preoperatorio, intraoperatorio y postoperatorio de la persona amputada, la prescripción de la prótesis y la rehabilitación integral. Estos ejercicios se ejecutan a través de tres videojuegos que permiten mantener la movilidad articular en la fase preoperatoria, mejorar el equilibrio monopodal en la fase preprotésica y realizar trabajos de equilibrio y coordinación durante la fase postprotésica. Adicionalmente, hacer la rehabilitación por medio de un videojuego promueve la motivación, la adherencia al tratamiento y permite controlar y evaluar los ejercicios de manera numérica y objetiva. Esto representa una innovación en la forma como las personas de lugares apartados puedan realizar ejercicios de rehabilitación, que contribuya a contrarrestar los factores que agudizan los problemas de salud a los que se exponen la personas con discapacidad.