tensor fascia lata origin: – anterior aspect of iliac crest – anterior superior iliac spine...

TENSOR FASCIA LATA• Origin:

– anterior aspect of iliac crest – anterior superior iliac spine (ASIS)

• Insertion: anterior aspect of IT band, below greater trochanter • Action:

– hip flexion – medially rotate & abduct a flexed thigh – tenses IT tract to support femur on the tibia during standing

• Blood: – superior gluteal artery – lateral femoral circumflex artery

• Nerve: superior gluteal nerve, L4,5,S1

TENSOR FASCIA LATA (cont’d)

GLUTEUS MAXIMUS• Origin:

– outer rim of ilium (medial aspect) – dorsal surface of sacrum and coccyx – sacrotuberous ligament

• Insertion: – IT band (primary insertion) – gluteal tuberosity of femur

• Action: – powerful extensor of hip – laterally rotates thigh – upper fibers aid in abduction of thigh – fibers of IT band stabilize a fully extended knee

• Blood: – inferior gluteal artery (primary) – superior gluteal artery

• Nerve: inferior gluteal nerve, L5,S1,2

GLUTEUS MAXIMUS (cont’d)

GLUTEUS MEDIUS• Origin:

– outer aspect of ilium (between iliac crest and anterior and posterior gluteal lines)

– upper fascia (AKA gluteal aponeurosis)• Insertion: superior aspect of greater trochanter • Action:

– anterior and lateral fibers abduct and medially rotate the thigh – posterior fibers may laterally rotate thigh – stabilizes the pelvis and prevents free limb from sagging during

gait• Blood: superior gluteal artery • Nerve: superior gluteal nerve, L4,5,S1

GLUTEUS MEDIUS (cont’d)

GLUTEUS MINIMUS• Origin: outer aspect of ilium (between anterior and

inferior gluteal lines) • Insertion: – greater trochanter (anterior to medius) – articular capsule of hip joint

• Action: – abduct and medially rotate the thigh – stabilizes the pelvis and prevents free limb from sagging

during gait• Blood: superior gluteal artery • Nerve: superior gluteal nerve, L4,5,S1

GLUTEUS MINIMUS (cont’d)

GLUTEAL MUSCLES

PIRIFORMIS• Origin: pelvic surface of sacrum (anterior portion) • Insertion: medial surface of greater trochanter

(through greater sciatic foramen) • Action: – lateral rotation of extended thigh – abducts a flexed thigh

• Blood: – superior gluteal artery – inferior gluteal artery

• Nerve: nerve to piriformis, S1,2

PIRIFORMIS (cont’d)