In an "unhappy triad" the ACL and medial meniscus is often torn due to their common attachments. Based on this, what portion of the medial meniscus is most likely torn?
a) the anterior horn of the medial aspect
b) the entire coronary ligament
c) the posterior horn of the medial aspect
d) the posterior horn of the lateral aspect
e) the mid-portion of the meniscus
I'm leaning towards answer choice C.
To determine which portion of the medial meniscus is most likely torn in an "unhappy triad" injury, we need to understand the anatomy and biomechanics involved. The "unhappy triad" refers to a combination of three simultaneous injuries: a tear of the anterior cruciate ligament (ACL), tear of the medial collateral ligament (MCL), and a tear of the medial meniscus.
The ACL, MCL, and medial meniscus are all connected and share common attachments, making them susceptible to injury when a rotational force is applied to the knee joint. In this injury, the force causes the tibia (shinbone) to forcefully move laterally (sideways) while the femur (thighbone) is stationary or moves in the opposite direction.
In this scenario, the ACL is torn due to its role in stabilizing the knee against front-to-back (anterior-posterior) translation. The MCL is torn because it is located on the inner (medial) side of the knee joint and provides stability against inward (valgus) forces. Lastly, the medial meniscus is torn due to its attachments to the MCL and its role in cushioning and stabilizing the knee joint.
Given these factors, the most likely portion of the medial meniscus to be torn in an "unhappy triad" injury is the anterior horn of the medial aspect (option a). This is because the MCL often tears from its attachment on the medial meniscus, leading to injury in this region.
Therefore, the correct answer is option a) the anterior horn of the medial aspect.