Muscles of the Lower Limb

Question 1

Pectineus

Answer 1

Proximal: superior ramus of pubis

Distal: pectineal line of femur, just inferior to lesser trochanter

Innervation: Femoral nerve

Action: flexes and abducts hip joint. Assist medial rotation of hip joint

Question 2

Sartorius “tailor’s muscle”

Answer 2

Longest strap-like running obliquely crosses thigh

Proximal: anterior superior iliac spine

Distal: superior part of medial surface of tibia

Innervation: Femoral nerve

Action: flexes, abducts, lateral rotation thigh at hip; flexes leg at knee joint (cross-leg position)

Question 3

Rectus Femoris

Answer 3

Proximal: anterior inferior iliac spine; above acetabulum

Distal: via quadriceps tendon at base of patella

Innervation: Femoral nerve

Action: extends knee joint; stabilizes hip joint

Question 4

Vastus lateralis

Answer 4

Proximal: greater trochanter, lateral lip of linea aspera

Distal: quadriceps tendon at base of patella

Innervation: Femoral nerve

Action: extends knee joint

Question 5

Vastus medialis

Answer 5

Proximal: intertrochantric line; medial lip of linea aspera

Distal: quadriceps tendon at base of patella

Innervation: Femoral nerve

Action: extends knee joint

Question 6

Vastus intermedius

Answer 6

Proximal: anterior and lateral surfaces of shaft of femur

Distal: quadriceps tendon at base of patella

Innervation: Femoral nerve

Action: extends knee joint

Question 7

Adductor longus

Answer 7

Proximal: body of pubis inferior to pubic crest

Distal: middle third of linea aspera of femur

Innervation: Obturator nerve

Action: adducts thigh (astride horse)

Question 8

Adductor brevis

Answer 8

Proximal: body and inferior ramus of pubis

Distal: pectineal line and proximal linea aspera

Innervation: Obturator nerve

Action: adducts thigh

Question 9

Adductor magnus

Answer 9

Proximal: adductor part- inferior ramus of pubis and ramus of ischium; hamstrung part- ischial tuberosity

Distal: adductor part- gluteal tuberosity, linea aspera, medial supracondylar line; hamstring part- adductor tubercle of femur

Innervation: add- Obturator nerve; ham- Sciatic nerve

Action: adducts hip joint, flexion and extension (hamstring part) of hip joint

Question 10

Gracilis

Answer 10

Proximal: body and inferior ramus of pubis

Distal: superior part of medial surface of tibia

Innervation: Obturator nerve

Action: Adducts hip joint, flexes leg

Question 11

Obturator externus

Answer 11

Proximal: margins off Obturator foramen and Obturator membrane

Distal: trochantric fossa of femur

Innervation: Obturator nerve

Action: lateral rotation of hip joint, stabilize hip

Question 12

Superficial layer of gluteal muscles

Answer 12

1. Gluteus maximus
2. Gluteus medius
3. Gluteus minimus
4. Tensor fascia latae

Question 13

Gluteus Maximus

Answer 13

Largest and most superficial glueteal muscle

Proximal: posterior to posterior gluteal line; posterior surface of sacrum and coccyx; sacrotuberous ligament

Distal: iliotibial tract “IT band” which inserts into lateral condyle of tibia; gluteal tuberosity of femur

Innervation: inferior gluteal nerve

Action: extends hip joint; assist lateral rotation

Question 14

Gluteus medius

Answer 14

Proximal: between anterior and posterior gluteal lines

Distal: lateral surface of greater trochanter

Innervation: superior gluteal nerve

Action: abduct and medial rotation of thigh; keep pelvis level when opposite leg is raised during walking

Question 15

Gluteus minimus

Answer 15

Proximal: ilium between anterior and inferior lines

Distal: anterior surface of greater trochanter

Innervation: superior gluteal nerve

Action: abduct and medial rotation of thigh

Question 16

Tensor fasciae latae

Answer 16

Proximal: ASIS; anterior part of iliac crest

Distal: iliotibial tract which attaches to lateral condyle of tibia

Innervation: superior gluteal nerve

Action: flexion of thigh

Question 17

Piriformis

Answer 17

Passes through greater sciatic foramen

Proximal: anterior surface of 2nd-4th sacra segments; superior margin of greater sciatic notch; sacrotuberous ligament

Distal: superior border of greater trochanter

Innervation: anterior rami of S1, S2

Action: lateral rotation of extended thigh; abduction of flexes thigh; stabilize hip joint

Question 18

Obturator internus

Answer 18

Passes through lesser sciatic foramen

Proximal: pelvic surface of ilium & ischium; Obturator membrane

Distal: medial surface of greater trochanter (90° bend)

Innervation: nerve to obturator internus

Action: laterally rotates extended thigh; abducts flexes thigh; stabilize hip

Question 19

Superior and inferior gemelli

Answer 19

Proximal: superior from ischial spine and inferior from ischial tuberosity

Distal: medial surface of greater trochanter

Innervation: superior from nerve to obturator internus; inferior from nerve to quadratus femoris

Action: laterally rotates extended thigh; abducts flexes thigh; stabilizes hip joint

Question 20

Quadratus femoris

Answer 20

Proximal: lateral border of ischial tuberosity

Distal: quadrate tubercle on intertrochantric crest

Innervation: nerve to quadratus femoris

Action: lateral rotation of thigh, stabilize hip joint

Question 21

Semitendinosus

Answer 21

Proximal: ischial tuberosity

Distal: medial aspect of superior part of tibia

Innervation: tibial division of sciatic nerve

Action: extend thigh; flex leg and rotate medially when knee is flexes; when thigh and leg are flexed can extend trunk

Question 22

Semimembranosus

Answer 22

Proximal: ischial tuberosity

Distal: posterior part of medial condyle of tibia

Innervation: tibial division of sciatic nerve

Action: extend thigh; flex leg and rotate it medially when knee is flexed; when thigh and leg are flexed can extend trunk

Question 23

Biceps femoris, long & short head

Answer 23

Proximal: long head- ischial tuberosity; short head- linea aspera

Distal: lateral side of fibula

Innervation: long- tibial division of sciatic nerve; short- common fibular division of sciatic nerve

Action: flexes leg and lateral rotation when knee is flexed; extends thigh (when start to walk)

Question 24

Femoral triangle boundaries

Answer 24

Superiorly: inguinal ligaments
Medially: adductor longus
Laterally: sartorius
Apex: crossing of medial border of sartorius and lateral border of adductor longus
Floor: iliopsoas and pectineus
Roof: fascia lata, cribriform fascia, subcutaneous tissue and skin

Question 25

Femoral triangle contents

Answer 25

Femoral never 
Femoral artery
Femoral vein
Femoral canal
Deep inguinal lymph nodes and lymphatic vessels