Which muscle lies lateral to the sartorius?

• A. Tensor fasciae latae
• B. Rectus femoris
• C. Biceps femoris
• D. Semitendinosus

Answer: (A)

Understanding how thigh muscles relate to each other in space helps you identify what sits on the outside of the sartorius. The sartorius runs obliquely across the front of the thigh from the hip to the medial leg. On its lateral side at the proximal thigh is the tensor fasciae latae, which originates from the iliac crest and ASIS and blends into the iliotibial tract along the outer thigh. The other options reside in different parts of the thigh: rectus femoris is a central anterior muscle, while the biceps femoris and semitendinosus are posterior thigh muscles. So the muscle lying lateral to the sartorius is the tensor fasciae latae.