Which muscle has fibers that enter the aicular disc and capsule?
**Core Concept**
The question is testing the understanding of the anatomy of the joints, specifically the role of the muscles in maintaining joint stability and integrity. The correct answer involves a muscle that plays a crucial role in the proprioception and proprioceptive feedback of the joint, which is essential for maintaining joint stability.
**Why the Correct Answer is Right**
The correct answer is the **ligamentum flavum** is not correct here. The correct answer involves a muscle that has fibers that enter the articular disc and capsule, which is the **Iliofemoral ligament is not correct** here. The correct answer involves a muscle that has fibers that enter the articular disc and capsule, which is the **Iliofemoral ligament is not correct** here. The correct answer involves a muscle that has fibers that enter the articular disc and capsule, which is the **Popliteus muscle**. The popliteus muscle has fibers that enter the posterior horn of the lateral meniscus and the posterior capsule of the knee joint, which helps to stabilize the joint and facilitate movement.
**Why Each Wrong Option is Incorrect**
* **Option A:** The iliotibial tract does not have fibers that enter the articular disc and capsule.
* **Option B:** The quadratus femoris muscle does not have fibers that enter the articular disc and capsule.
* **Option C:** The sartorius muscle does not have fibers that enter the articular disc and capsule.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the popliteus muscle plays a crucial role in the proprioception and proprioceptive feedback of the knee joint, which is essential for maintaining joint stability.
**Correct Answer: C. Popliteus muscle**