Which muscle flexes the hip and medial rotates the hip, and also provides knee joint support?

• A. Tensor Fasciae Latae
• B. Iliopsoas
• C. Gluteus Maximus
• D. Sartorius

Answer: (A)

The important idea is how a muscle can coordinate hip motion and also contribute to knee stability through its tendon. The Tensor fasciae latae sits on the outer hip and, when it contracts, it helps flex the hip and, because of its line of pull, medially rotates the thigh. Its tendon forms the iliotibial tract, which runs down the side of the leg to the knee. Tension in that tract helps stabilize the knee during movement, giving knee joint support.

Iliopsoas mainly powers hip flexion but doesn’t provide notable medial rotation or knee stabilization. Gluteus maximus mainly extends and externally rotates the hip, not medially rotates it or stabilizes the knee in this way. Sartorius crosses both joints and does hip flexion and knee flexion, with some diagonal actions, but it isn’t the primary source of knee stabilization via a tract like the iliotibial band.

So the combination of hip flexion, hip internal rotation, and knee stabilization through the iliotibial tract points to the tensor fasciae latae.