lower extremity attachments, actions, nerve supply

gluteal and posterior thigh regions

proximal attachment - gluteus maximus muscle

ilium posterior to posterior gluteal line; dorsal sacrum and coccyx; sacrotuberous ligament

distal attachment - gluteus maximus muscle

illotibital (and gluteal tuberosity)

nerve supply - gluteus maximus muscle

inferior gluteal nerve

actions - gluteus maximus

extends hip joint (especially from flexed position)

aids in lateral/external rotation of thigh (interchangeable)

stabilizes thigh, rising from sitting position

proximal attachment - gluteus medius muscle

external ilium between anterior and posterior gluteal lines

distal attachment - gluteus medius muscle

(lateral side of) greater trochanter

nerve supply - gluteus medius

superior gluteal nerve (innervation)

action - gluteus medius muscle

abduction hip joint

medial/internal motion of thigh

keeps upright when walking

proximal attachment - gluteus minimus muscle

external ilium between anterior and inferior gluteal lines

distal attachment - gluteus minimus muscle

(anterior surface of) greater trochanter

nerve supply - gluteus minimus

superior gluteal nerve

action - gluteus minimus

abduct hip joint

medial/internal rotation of thigh

proximal attachment - tensor fascia latae

anterior superior iliac spine

distal attachment - tensor fascia latae

illotibial tract (IT band)

nerve supply - tensor fascia lata

superior gluteal n.

actions - tensor fascia latae

abduct hip joint

medial/internal rotation

creates extra tension, helps contract and flex

proximal attachment- piriformis muscle

anterior surface of sacrum; sacrotuberous ligament

distal attachment - piriformis muscle

(superior border) greater trochanter

nerve supply - piriformis

nerve to piriformis

action - piriformis muscle

lateral/external rotation of thigh

abduction flexed thigh

proximal attachment - obturator internus muscle

internal surface of obturator foramen and membrane

distal attachment - obturator internus

trochanteric fossa on femur

nerve innervation- obturator internus

nerve to obturator

action - obturator internus

lateral/external rotation of hip

abduct flexed thigh

proximal attachment - inferior gemellus

ischial tuberosity

distal attachment - inferior gemellus

trochanteric fossa on femur

nerve innervation - inferior gemellus

nerve to quadratus

action -inferior gemellus

Lateral/external rotation of hip

abduct flexed thigh

triceps coaxe - distal attachment

gemelli muscles attach to tendon of obturator internus

proximal attachment - quadratus femurs

ischial tuberosity (lateral surface)

distal attachment - quadratus femoris

intertrochanteric cers (quadrate tubercle)

nerve innervation - quadratus femoris

nerve to quadratus femoris

actions - quadratus femoris

lateral/external rotation of thigh

deep hip rotator

nerves of gluteal region

• superior gluteal

• inferior gluteal

• pudendal

• nerve to quadratus femoris

• posterior femoral cutaneous

• sciatic

super and inferior gluteal arteries

derive from internal iliac artery

semitendinosus muscle - proximal attachment

ischial tuberosity

distal attachment - semiteninosus muscle

supero-medial(upper front) surface tibia (part of pes anserinus)

nerve supply - semitendinosus muscle

tibial division of sciatic nerve

actions - semitendinosus

extends hip joint when trunk bent forward (controls forward flexion of trunk @ hip joint-eccentrically)

flex knee joint, with semi flexion —> medial rotation present

affixed foot on ground —→ lateral rotate the hip (stationary tibia)

muscle insertion - Pes anserinus (‘such good tendon’)

‘goose foot’ shape at muscle insertion site, on superior medial tibia

• sartorius muscle (anterior compartment)

• gracilis muscle (medial compartment)

• semitendinosus muscle (posterior)

proximal attachment - semimembranosus muscle

ischial tuberosity

distal attachment - semimembranosus

posterior surface of medial tibial condyle

nerve supply - semimebranosus muscle

tibial division of the sciatic nerve

actions - semimembranosus

extends hip joint when trunk bent forward (controls forward flexion of trunk @ hip joint-eccentrically)

flex knee joint, with semi flexion —> medial rotation present

affixed foot on ground —→ lateral rotate the hip (stationary tibia)

proximal attachment - long head of biceps femoris

ischial tuberosity

distal attachment - long head biceps femoris

lateral side of fibular head

nerve supply - long head biceps femoris

tibial division of the sciatic nerve

action - long head biceps femoris

extends hip joint when trunk bent forward (controls forward flexion of trunk @ hip joint-eccentrically)

flex knee joint, with semi flexion —> lateral rotation at knee present

proximal attachment - biceps femoris short head

lower half of the linea aspera; lateral supracondylar ridge

distal attachment - biceps femoris short head

lateral side of fibular head

nerve supply - short head of biceps femoris

common fibular division of the sciatic nerve

actions - short head of biceps femoris

flex knee joint, semi-flexion —> lateral rotation at knee

proximal attachment - ischiocondylar portion of adductor Magnus muscle

ischial tuberosity

distal attachment - ischiocondylar portion of adductor magnus

adductor tubercle (femur)

nerve supply - ischiocondylar portion of adductor magnus

tibial division of sciatic nerve

• adductor component is innervated by obturator nerve of medial thigh

action - ischiocondylar portion of adductor magnus

extend hip joint

‘hamstring’ attachments

(Other than BFSH) extends from posteroinferior pelvis to posterior knee (ST & SM medial “hamstrings”; BFLH lateral “hamstring”)

actions of ‘hamstring’

• hip extension when trunk is flexed position (in lengthened state)

• knee flexion

• pelvic tilt (anterior-posterior)

• swing phase of walking —> deceleration forward motion of tibia

nerve innervation - posterior thigh

sciatic nerve - emerges from piriformis muscle