IMS Lower Limb Musculature Origins, Insertions, Innervations and Functions

piriformis origin

anterior surface of the sacrum between anterior sacral foramina

piriformis insertion

Superior border of greater trochanter of femur

piriformis innervation

Sacral plexus (S1, S2)

piriformis function

laterally rotates the thigh, abducts the thigh

obturator internus origin

deep surface of obturator membrane (anterolateral wall)

obturator internus insertion

trochanteric fossa of femur

obturator internus innervation

Sacral plexus (L5, S1)

obturator internus function

laterally rotates thigh

obturator externus origin

obturator membrane and foramen (posterior and medially)

obturator externus insertion

trochanteric fossa of femur

obturator externus fuction

laterally rotates the thigh

obturator exturnus innervation

obturator nerve (L3, L4)

gemellus superior origin

external surface of ischial spine

gemellus superior insertion

trochanteric fossa of femur

gemellus superior action

laterally rotate thigh

gemellus superior innervation

Sacral plexus (L5, S1)

gemellus inferior origin

ischial tuberosity

gemellus inferior insertion

trochanteric fossa

gemellus inferior innervation

Sacral plexus (L5, S1)

gemellus inferior action

laterally rotate thigh

quadratus femoris origin

lateral border of ischial tuberosity

quadratus femoris insertion

intertrochanteric crest

quadratus femoris innervation

sacral plexus (L5, S1)

quadratus femoris action

laterally rotates thigh

gluteus maximus origin

dorsal ilium, sacrum, coccyx, sacrotuberous ligament

gluteus maximus insertion

gluteal tuberosity of femur and iliotibial tract

gluteus maximus action

extends and laterally rotates thigh

gluteus maximus innervation

Inferior gluteal nerve (L5, S1, S2)

gluteus medius origin

External surface of ilium between anterior and posterior gluteal lines (superior surface of the ilium)

gluteus medius insertion

greater trochanter of femur

gluteus medius innervation

Superior gluteal nerve (L4, L5, S1, primarily L5)

gluteus medius action

abducts, medially and laterally rotates the thigh

gluteus minimus origin

external surface of ilium between anterior and inferior gluteal lines (inferior surface of ilium)

gluteus minimus insertion

greater trochanter of femur

gluteus minimus innervation

Superior gluteal nerve (L4, L5, S1)

gluteus minimus action

abducts and medially rotates thigh

tensor fasciae latae origin

iliac crest, anterior superior iliac spine

tensor fasciae latae insertion

iliotibial tract (IT band)

tensor fasciae latae innervation

Superior gluteal nerve (L4-S1)

tensor fasciae latae action

abducts medially rotates the thigh

rectus femoris origin

AIIS

rectus femoris insertion

tibial tuberosity via patellar ligament (quadriceps tendon)

rectus femoris innervation

Femoral nerve (L2-L4)

rectus femoris action

flexes thigh, extends leg

vastus lateralis origin

lateral lip of the linea aspera

vastus lateralis insertion

tibial tuberosity via patellar ligament (quadriceps tendon)

vastus lateralis action

extends leg

vastus lateralis innervation

Femoral nerve (L2-L4)

vastus medialis origin

medial lip of linea aspera

vastus medialis insertion

tibial tuberosity via patellar ligament (quadriceps tendon)

vastus medialis innervation

Femoral nerve (L2-L4)

vastus medialis action

extends leg

vastus intermedius origin

anterior and lateral shaft of femur

vastus intermedius insertion

tibial tuberosity via patellar ligament (quadriceps tendon)

vastus intermedius action

extends leg

vastus intermedius innervation

Femoral nerve (L2-L4)

psoas major origin

T12-L5 vertebral bodies and disks

L1-5 transverse processes

psoas major insertion

lesser trochanter of femur

psoas major innervation

Femoral nerve (L2-L4)

psoas major action

flexes thigh

iliacus origin

iliac fossa

iliacus insertion

lesser trochanter of femur

iliacus action

flexes thigh

iliacus innervation

Femoral nerve (L2-L4)

sartorius origin

ASIS

sartorius insertion

AMP (anterior medial proximal tibia/pes anserinus)

sartorius innervation

Femoral nerve (L2-L4)

sartorius action

flexes, abducts, and laterally rotates thigh; flexes knee

pectineus origin

superior ramus of pubis

pectineus insertion

pectineal line of femur

pectineus action

adducts and flexes thigh

pectineus innervation

Femoral nerve (L2-L4)

adductor longus origin

body of pubis

adductor longus insertion

middle 1/3 of linea aspera

adductor longus innervation

Obturator nerve (L2-L4)

adductor longus action

adducts and medially rotates thigh

adductor brevis origin

inferior ramus of pubis

adductor brevis insertion

pectineal line and medial lip of the linea aspera of femur

adductor brevis action

adducts thigh

adductor brevis innervation

Obturator nerve (L2-L4)

adductor magnus origin

Inferior ramus of the pubis, ramus of ischium and ischial tuberosity

adductor magnus insertion

gluteal tuberosity, medial lip of linea aspera, and adductor tubercle of the femur

adductor magnus action

adducts and extends thigh (hamstrings portion)

adductor magnus innervation

Obturator nerve (L2-L4)

gracilis origin

body and inferior ramus of pubis

gracilis insertion

anterior medial proximal surface of tibia (AMP/pes anserinus)

gracilis action

adducts thigh and flexes leg

gracilis innervation

obturator nerve (L2-L4)

biceps femoris origin

ischial tuberosity

biceps femoris insertion

head of fibula

biceps femoris action

extends thigh and flexes leg

biceps femoris innervation

long head= tibial division of sciatic nerve (L5-S3)

short head= common fibular division of sciatic nerve (L5-S2)

semitendinosus origin

ischial tuberosity

semitendinosus insertion

medial surface of proximal tibia (AMP or pes anserinus)

semitendinosus action

extends thigh and flexes leg

semitendinosus innervation

tibial division of sciatic nerve (L5-S3)

semimembranosus origin

ischial tuberosity

semimembranosus insertion

medial condyle of tibia (Posterior medial proximal tibia or PMP)

semimembranosus innervation

tibial division of sciatic nerve (L5-S3)

semimembranosus action

extends thigh and flexes leg