<prompt> During a football game a 21-year-old wide receiver was illegally blocked by a linebacker, who threw himself against the posterolateral aspect of the runners left knee. As he lay on the ground, the wide receiver grasped his knee in obvious pain. Which of the following structures is frequently subject to injury from this type of force against the knee?Fibular collateral ligamentAnterior cruciate ligamentLateral meniscus and posterior cruciate ligamentFibular collateral and posterior cruciate ligament  <response>: This type of injury can result in the unhappy triad of ODonahue injury, with damage to the medial collateral ligament MCL, anterior cruciate ligament ACL, and medial meniscus. A blow to the lateral side of the knee stretches and tears the MCL, which is attached to the medial meniscus. The ACL is tensed during knee extension and can tear subsequent to the rupture of the MCL. The remaining answer choices describe structures on the lateral surface of the knee, which are not usually injured by this type of trauma. 