Question

The type of force that typically causes injury to the medial collateral ligament (MCL), medial meniscus, and anterior cruciate ligament (ACL) of the knee is:

A) Hyperextension

B) Valgus force (force from the outside of the knee, pushing inward)

C) Varus force (force from the inside of the knee, pushing outward)

D) Hyperflexion

Answer 1

Injuries to the MCL, medial meniscus, and ACL often occur due to a valgus force, with the foot planted and the force coming from the lateral side of the knee, causing a 'terrible triad' of injuries.

Step-by-step explanation:

The type of force that typically causes injury to the medial collateral ligament (MCL), medial meniscus, and anterior cruciate ligament (ACL) of the knee is: B) Valgus force (force from the outside of the knee, pushing inward). A strong blow to the lateral side of the extended knee can result in a sequence of injuries, starting with the tearing of the MCL, damage to the medial meniscus, which is attached to the MCL, and finally, rupture of the ACL. This sequence of injuries is known as the "terrible triad." These types of injuries are common when the foot is planted and a force is applied from the outside of the knee, which causes the knee to buckle inward, stressing the structures on the medial side of the knee.

The MCL serves to resist hyperextension and rotation of the extended knee joint. However, a moderate blow to the lateral knee, or knee's outer side, can cause stretching or damage to the MCL and also injure the attached medial meniscus, explaining why the medial meniscus is more frequently injured compared to the lateral meniscus. A powerful blow can escalate this injury by also involving the ACL.

Answer 2

A Valgus force, which is a force from the outside of the knee pushing inward, typically causes injury to the MCL, medial meniscus, and ACL, leading to a 'terrible triad' pattern of knee injuries.

Step-by-step explanation:

The type of force that typically causes injury to the medial collateral ligament (MCL), medial meniscus, and anterior cruciate ligament (ACL) of the knee is a Valgus force (force from the outside of the knee, pushing inward). This kind of force can occur when there is a strong blow to the lateral side of the extended knee, leading to a 'terrible triad' injury pattern that sequentially affects the tibial collateral ligament, medial meniscus, and ACL. The medial meniscus is particularly prone to damage because it is attached to the tibial collateral ligament, making it more susceptible to injury when the knee joint is subjected to a valgus force.