Anterior superior iliac spine

Muscles attaching or palpated here

• External oblique — Broad, outermost muscle of the side of the abdomen that flexes, side-bends and rotates the trunk to the opposite side.
• Gluteus medius — Thick, fan-shaped muscle on the outer side of the pelvis that abducts the hip and keeps the pelvis level when you stand on one leg.
• Gluteus minimus — The smallest and deepest of the three gluteal muscles, lying under gluteus medius, that abducts and medially rotates the hip.
• Iliopsoas — Deep hip flexor made of psoas major and iliacus, running from the lumbar spine and inside of the pelvis to the lesser trochanter of the femur, and the strongest flexor of the hip.
• Internal oblique — Middle layer of the side abdominal wall, lying under the external oblique, that flexes the trunk, compresses the abdomen and rotates the trunk to the same side.
• Quadriceps — Group of four large muscles on the front of the thigh that join into one tendon over the kneecap and are the only muscles that straighten the knee.
• Rectus femoris — Spindle-shaped muscle down the middle of the front of the thigh, the only quadriceps muscle that crosses the hip, so it both flexes the hip and straightens the knee.
• Sartorius — Long, thin strap muscle, the longest in the body, running diagonally across the front of the thigh from the ASIS to the inner knee, which helps flex, abduct and laterally rotate the hip and bend the knee.
• Tensor fasciae latae — Small muscle at the front of the outer hip, just below the ASIS, that tightens the iliotibial band and helps flex, abduct and medially rotate the hip.
• Transversus abdominis — Deepest of the abdominal wall muscles, wrapping horizontally around the waist like a corset to compress the abdomen and help stabilise the trunk.