Upper Leg 2

Muscle Actions of the Hip

  • Flexion: Decreases joint angle, moving the thigh toward the trunk.

  • Extension: Increases joint angle, straightening the hip.

  • Abduction: Movement away from the body's midline.

  • Adduction: Movement toward the midline.

  • Medial (Internal) Rotation: Rotating the leg so toes point toward each other.

  • Lateral (External) Rotation: Rotating the leg so toes point outward, similar to first position in ballet.

Primary Flexors and Anterior Muscles

  • Iliopsoas: A combination of 22 muscles, the psoas major and iliacus; originates on the lumbar vertebra and ilium, inserting into the lesser trochanter of the femur to perform hip flexion.

  • Pectineus: Short muscle originating on the superior ramus of the pubis and inserting on the femur between the lesser trochanter and linea aspera; performs hip flexion and adduction.

  • Sartorius: Originates on the anterior superior iliac spine and inserts on the proximal medial tibia; produces weak hip flexion, abduction, and lateral rotation, plus weak knee flexion.

  • Tensor fascia latae: Originates on the iliac crest and inserts into the tibia via the ilio tibial tract (or ilio tibial band); performs hip flexion and abduction.

Gluteal and Posterior Muscles

  • Gluteus maximus: Largest of the 33 gluteal muscles; originates on the iliac crest, sacrum, and coccyx, and inserts on the gluteal tuberosity to extend the hip and assist in lateral rotation.

  • Gluteus medius: Originates on the ilium and inserts on the greater trochanter; performs abduction and medial rotation.

  • Gluteus minimus: Smallest gluteal muscle lying deep to the gluteus medius; originates on the ilium and inserts on the greater trochanter to perform abduction and medial rotation.

  • Lateral rotators: A group of 66 small, deep muscles on the posterior surface that cause lateral rotation of the hip joint.

Medial Adductor Group

  • Adductor brevis: A short muscle originating on the inferior ramus of the pubis and inserting on the superior half of the linea aspera; performs adduction and hip flexion.

  • Adductor magnus: A large muscle (magnus meaning large) originating on the inferior ramus of the pubis, ischium, and ischial tuberosity; the anterior portion helps flex the hip while the posterior portion helps extend it.

  • Adductor longus: Originates on the pubic crest and pubic symphysis, inserting on the linea aspera to produce adduction and hip flexion.

  • Gracilis: Runs along the midline of the leg, originating on the pubis and inserting on the tibia; causes adduction, medial rotation, and knee flexion.

Blood Vessels of the Upper Leg

  • Femoral arteries: Main vessels running the length of the femur; continuations of the external iliac arteries.

  • Deep femoral artery: A branch of the femoral artery that reaches deeper structures within the thigh.

  • Femoral vein: A continuation of the popliteal vein as it ascends from the posterior of the knee.