Lower Limb Muscles

Question 1

pectineus

Answer 1

origin: superior ramus of pubis
insertion: pectineal line of femur, just inferior to lesser trochanter
action: adduct and flex hip joint; assist with medial rotation of hip

blood supply: medial circumflex femoral artery and obturator artery

innervation: femoral nerve (L2, L3)

Question 2

iliacus

Answer 2

WORKS WITH PSOAS MAJOR TO FORM THE ILIOPSOAS MUSCLE, WHICH IS THE CHIEF FLEXOR OF THE HIP

origin: iliac crest, iliac fossa, ala of sacrum, anterior sacro-iliac ligaments
insertion: tendon of psoas major, lesser trochanter, and femur
action: acts with PSOAS MAJOR to flex hip and stabilize the hip joint

blood supply: iliac branches of iliolumbar artery

innervation: femoral nerve (L2, L3)

Question 3

psoas major

Answer 3

WORKS WITH ILIACUS TO FORM THE ILIOPSOAS MUSCLE, WHICH IS THE CHIEF FLEXOR OF THE HIP

origin: sides of T12-L5 vertebrae and their discs, transverse processes of lumbar vertebrae
insertion: lesser trochanter of femur
action: acts with ILIACUS to flex hip and stabilize the hip joint; active during standing as a postural muscle

blood supply: lumbar branches of iliolumbar artery

innervation: ventral rami of lumbar nerves (L1, L2, L3)

Question 4

sartorius

Answer 4

origin: ASIS and superior part of notch inferior to it
insertion: superior part of medial surface of tibia
action: flex, abduct, laterally rotate hip joint (when working bilaterally, brings into cross-legged sitting position), flex knee joint

blood supply: femoral artery

innervation: femoral nerve (L2, L3)

Question 5

rectus femoris

Answer 5

QUADRICEPS FEMORIS

origin: anterior inferior iliac spine and ilium superior to acetabulum
insertion: base of patella; tibial tuberosity via patellar ligament
action: extend knee joint; stabilize hip joint and helps ilipsoas flex hip joint

blood supply: profunda femoris artery and lateral circumflex femoral artery

innervation: femoral nerve (L2, L3, L4)

Question 6

vastus lateralis

Answer 6

QUADRICEPS FEMORIS

origin: greater trochanter and lateral lip of linea aspera
insertion: base of patella; tibial tuberosity via patellar ligament
action: extend knee joint

blood supply: profunda femoris artery and lateral circumflex femoral artery

innervation: femoral nerve (L2, L3, L4)

Question 7

vastus medialis

Answer 7

QUADRICEPS FEMORIS

origin: intertrochanteric line and medial lip of linea aspera
insertion: base of patella; tibial tuberosity via patellar ligament
action: extend knee joint

blood supply: femoral artery and profunda femoris artery

innervation: femoral nerve (L2, L3, L4)

Question 8

vastus intermedius

Answer 8

QUADRICEPS FEMORIS

origin: anterior and lateral surfaces of shaft of femur
insertion: base of patella; tibial tuberosity via patellar ligament
action: extend knee joint

blood supply: lateral circumflex femoral artery and profunda femoris artery

innervation: femoral nerve (L2, L3, L4)

Question 9

adductor longus

Answer 9

origin: body of pubis inferior to pubic crest
insertion: middle 1/3 of linea aspera of femur
action: adduct hip joint

blood supply: profunda femoris artery and medial circumflex femoral artery

innervation: obturator (L2-L4)

Question 10

adductor brevis

Answer 10

origin: body and inferior ramus of pubis
insertion: pectineal line and proximal part of linea aspera of femur
action: adduct hip joint

blood supply: profunda femoris artery, medial circumflex femoral artery, obturator artery

innervation: obturator nerve (L2-L4)

Question 11

adductor magnus

Answer 11

origin: adductor part- inferior ramus of pubis and ramus of ischium; hamstring part- ischial tuberosity
insertion: adductor part- gluteal tuberosity, linea aspera, medial supracondylar line; hamstring part- adductor tubercle of femur
action: adduct hip joint; adductor part- flexes hip joint; hamstring part- extends hip joint

blood supply: femoral artery, obturator artery, profunda femoris artery

innervation: adductor part: obturator nerve (L2-L4); hamstring part- tibial part of sciatic nerve (L4)

Question 12

gracilis

Answer 12

origin: body and inferior ramus of pubis
insertion: superior part of medial surface of tibia
action: adduct hip joint; flex knee joint and rotate it medially

blood supply: profunda femoris artery, medial circumflex femoral artery

innervation: obturator nerve (L2, L3)

Question 13

obturator externus

Answer 13

origin: margins of obturator foramen and obturator membrane
insertion: trochanteric fossa of femur
action: laterally rotates hip joint; pulls femoral head into acetabulum

blood supply: medial circumflex femoral artery, obturator artery

innervation: obturator nerve (L3, L4)