American Board of Internal Medicine (ABIM) Certification Practice Exam

What does acute meniscal injury typically result from?

1. A fall on the knee

2. A twisting motion with the knee flexed

3. A direct hit to the knee

4. Long-term wear and tear

The correct answer is: A twisting motion with the knee flexed

Acute meniscal injury is most commonly associated with a twisting motion of the knee, especially when the knee is flexed. This mechanism puts significant stress on the knee joint and can lead to a tear of the meniscus, which is a C-shaped cartilage that helps cushion the knee joint and stabilize it. In situations where a twisting motion occurs, such as during activities that involve pivoting, rapid changes in direction, or sports like basketball and soccer, the meniscus can be subjected to forces that exceed its capacity to withstand them. When the knee is flexed, this can aggravate the situation as the positioning may place additional strain on the menisci, making them more prone to injury. The other options, while they may contribute to knee injuries, do not specifically align with how acute meniscal tears typically occur. A fall on the knee or a direct hit may lead to other types of knee injuries, such as fractures or ligament sprains, rather than a specific meniscal tear. Long-term wear and tear is associated with degenerative meniscal tears rather than acute injuries, which involve sudden trauma.