Muscles that act on the thigh Flashcards Preview

Gluteus maximus

Origin: dorsal ilium, sacrum, and coccyx

Insertion: gluteal tuberosity of femur, iliotibial tract

Major extensor of thigh; used when climbing stairs or running, generally inactive during standing and walking

Gluteus medius

Origin: between anterior and posterior gluteal lines on lateral surface of ilium

Insertion: by short tendon into lateral aspect of greater trochanter of femut

Abducts and medially rotates thigh; extremely important in walking

Gluteus minimus

Origin: between anterior and inferor gluteal lines on external surface of ilium

Insertion: anterior border of greater trochanter of femur

Same as gluteus maximus: major extensor of thigh; used in running and climbing but not walking

Piriformis

Origin: anterolateral surface of sacrum (opposite greater sciatic notch)

Insertion: superior border of greater trochanter of femur

Rotates extended thigh laterally

Quadratus femoris

Origin: ischial tuberosity

Insertion: intertrochanteric crest of femur

Rotates thigh laterally and stabilized hip joint

1. Iliacus

2. Psoas major

Iliacus

Origin: iliac fossa, ala of sacrum

Insertion: lesser trochanter of femur via iliopsoas tendon

Prime mover in thigh flexion and in flexing truck (as when bowing)

Psoas major

Origin: by fleshy slips from transverse processes, bodies, and discs of lumbar vertebrae and T12

Insertion: lesser trochanter of femur via iliopsoas tendon

Same as iliacus: primve mover in thigh flexion and flexing trunk (as in bowing); also causes lateral flexion of vertebral column

Pectineus

Origin: Pectineal line of pubis (and superior ramus)

Insertion: a line from lesser trochanter to the linea aspera on posterior aspect of femur

Adducts, flexes and medially rotates thigh

Adductor brevis

Origin: body and inferior ramus of pubis

Insertion: linea aspera above adductor longus

Adducts and medially rotates thigh

Adductor longus

Origin: pubis near pubic symphysis

Insertion: linea aspera

Adducts, flexes, and medially rotates thigh

Adductor magnus

Origin: ischia and pubic rami and ischial tuberosity

Insertion: linea aspera, media supracondylar line, and adductor tubercle of femur

Anterior part adducts and medially rotates and flexes thigh; posertior part is a synergist of hamstrings in thigh extension

Sartorius

Origin: anterior superior iliac spine

Insertion: winds around medial aspect of knee and inserts into medial aspect of proximal tibia

Flexes, abducts, and laterally rotates thigh; flexes knee (weak) as in soccer kick, helps you sit cross-legged

Rectus femoris

Origin: anterior inferior iliac spine and superior margin of acetabulum

Insertion: patella and tibial tuberosity via patellar ligament

Extends knee and flexes thigh at hip

Semimembranosus

Origin: ischial tuberosity

Insertion: medial condyle of tibia; through oblique ligament to lateral condyle of femur

Extends thigh and flexes knee; medially rotates knee

Semitendinosus

Origin: ischia tuberosity in common with long head of biceps femoris

Insertion: medial aspect of upper tibial shaft

Extends thigh at hip; flexes knee; with semimembranosus, medially rotates leg