Which muscle laterally rotates the hip?

Which muscle laterally rotates the hip?

• A. Vastus Medialis
• B. Biceps Femoris
• C. Gluteus Maximus' Lower Fibers
• D. Gracilis

Answer: (B)

External rotation of the hip occurs when the thigh is rotated outward at the hip joint. The biceps femoris is a biarticular muscle that crosses both the hip and the knee, so its pull can rotate the femur laterally, especially when the knee is flexed. This position allows the muscle to contribute to hip external rotation in a way the other options do not, whereas the vastus medialis acts mainly on the knee, gracilis functions as an adductor/internal rotator, and the gluteus maximus lower fibers are more about extension with external rotation in different positions. So, in the typical testing context, the biceps femoris best fits the idea of producing hip external rotation.

External rotation of the hip occurs when the thigh is rotated outward at the hip joint. The biceps femoris is a biarticular muscle that crosses both the hip and the knee, so its pull can rotate the femur laterally, especially when the knee is flexed. This position allows the muscle to contribute to hip external rotation in a way the other options do not, whereas the vastus medialis acts mainly on the knee, gracilis functions as an adductor/internal rotator, and the gluteus maximus lower fibers are more about extension with external rotation in different positions. So, in the typical testing context, the biceps femoris best fits the idea of producing hip external rotation.