Quadriceps protects the anterior cruciate ligament

Abstract

The aim of this study is to show that the quadriceps is the primary muscular restraint to anterior tibia1 translation during closed kinetic chain activities such as running, jumping, walking, and standing. It is my hypothesis that the quadriceps vector is directed superiorly during open kinetic chain knee extension and inferiorly during closed kinetic chain knee extension. My methods involve vector analysis based on a lateral radiograph of the normal human knee and muscle ultrasound. My results show that the quadriceps vector is directed superiorly for open kinetic chain knee extension and inferiorly for closed kinetic chain knee extension. The inferiorly directed quadriceps vector has an anterior femoral-tibia1 or posterior tibial-femoral component, which protects the anterior cruciate ligament (ACL) from anterior tibial-femoral shear. Therefore during closed kinetic chain activities, the quadriceps protects the ACL regardless of the activity of the hamstrizgs. Given that the quadriceps is much stronger than the hamstrings, has better leverage at low knee flexion angles, and a favorable vector with regard to the ACL during closed kinetic chain activities, and since most activities of daily living, sports, and non-contact ACL injuries occur with the foot on the ground, then it can be concluded that the quadriceps is theprimary ACLprotagonist. My findings have the following implications: (1) weak quadriceps are a risk factor for non-contact ACL injuries, (2) strong quadriceps are important for ACL injury prevention and rehabilitation, and (3) preservation of quadriceps strength is an important surgical goal.

An Alternative Mechanism of Non-contact Anterior Cruciate Ligament Injury During Jump-landing: In-vitro Simulation

“…We believe that the work by Aune et al [9] was accurate and the surrounding tissue that were cut played little role in their conclusions. Bodor [10] also supported the protective effect of the quadriceps using ultrasound techniques.…”

Silla bipedestadora para personas con movilidad restringida grado iv en las extremidades inferiores con una capacidad de carga de 100kg

“…Si la línea de gravedad pasa por el centro de cada articulación se aplica menos tensión sobre músculos y ligamentos. [18] Se considera a la rodilla como la articulación más grande del esqueleto humano, la misma que soporta la mayor parte del peso del cuerpo en posición de bipedestación, en ella se unen el fémur, la tibia y la rótula [27], esta articulación presenta una superficie cóncava que se desliza sobre otra convexa alrededor de 2 ejes, existen dos cuerpos que sirven como amortiguadores entre el fémur y la tibia, denominados los meniscos femorales [28] [29], desde el punto de vista morfológico la rodilla constituye la articulación encargada de la flexión y extensión de la pierna [30] [31]. La articulación de la rodilla realiza fundamentalmente movimientos en 2 planos perpendiculares entre sí (planos sagital y frontal) [27], posee un fuerte aparato ligamentoso, cuya función es darle estabilidad y evitar movimientos excesivos [28] [29].…”

Rules of physiotherapy after surgical reconstructions of ruptured anterior cruciate ligament

“…Na pourazowe dysfunkcje szczególnie narażony jest staw kolanowy [1][2][3]. Najczęściej powodem urazu jest nadmierna, przekraczająca aktualne możliwości fi zyczne organizmu, aktywność sportowa człowieka [4][5][6].…”

“…The knee joint is particularly prone to post-injury dysfunctions [1][2][3]. The most common cause of the injury is excessive sport activity which exceeds the real physical abilities of the body [4][5][6].…”