Week 3 Muscles Flashcards
Gluteus Maximus
O: Ilium posterior to posterior gluteal line, dorsal surface of sacrum and coccyx, sacrotuberous ligament
I: Most fibers end in iliotibial tract
that inserts into lateral condyle of tibia; some fibers insert into gluteal tuberosity of femur
I: Inferior gluteal nerve (L5, S1, S2)
B: Inferior gluteal arteries mainly,
and superior gluteal arteries occasionally
A: Extends flexed thigh, assists in lateral
rotation, and abducts thigh
Gluteus Medius
O: Lateral surface of ilium between anterior
and posterior gluteal lines
I: Lateral surface of greater
trochanter of femur
I: Superior gluteal nerve (L5, S1)
B: Superior gluteal artery
A: Abducts and medially rotates thigh at hips; steadies pelvis on leg when opposite leg is raised
Gluteus Minimus
O: Lateral surface of ilium between anterior
and inferior gluteal lines
I: Anterior surface of greater
trochanter of femur
I: Superior gluteal nerve (L5, S1)
B: Main trunk and deep branch of superior gluteal artery
A: Abducts and medially rotates thigh at hips; steadies pelvis on leg when opposite leg is raised
Inferior Gemellus
O: Ischial tuberosity
I: Medial surface of greater
trochanter of femur
I: Nerve to quadratus femoris
B: Medial circumflex femoral artery
A: Laterally rotates extended thigh at the hip
Superior Gemellus
O: Outer surface of ischial spine
I: Medial surface of greater
trochanter of femur
I: Nerve to obturator internus
B: Inferior gluteal and internal
pudendal arteries
A: Laterally rotates extended thigh at the hip
Tensor fasciae latae
O: Anterior superior iliac spine and anterior part of iliac crest
I: Iliotibial tract that attaches to
lateral condyle of tibia
I: Superior gluteal nerve (L5, S1)
B: Ascending branch of lateral
circumflex femoral artery
A: Abducts, medially rotates, and flexes thigh at hip; helps to keep knee extended
Piriformis
O: Anterior surface of sacral segments 2–4, sacrotuberous ligament
I: Superior border of greater
trochanter of femur
I: Ventral rami of L5, S1, S2
B: Superior and inferior gluteal arteries, internal pudendal artery
A: Laterally rotates extended thigh, abducts flexed thigh at hip
Obturator Internus
O: Pelvic surface of obturator membrane and surrounding bone
I: Medial surface of greater
trochanter of femur
I: Nerve to obturator internus (L5, S1)
B: Internal pudendal and obturator arteries
A: Laterally rotates extended thigh, abducts flexed thigh at hip
Quadratus Femoris
O: Lateral margin of ischial tuberosity
I: Quadrate tubercle on intertrochanteric crest of femur
I: Nerve to quadratus femoris (L5, S1)
B: Medial circumflex femoral artery
A: Laterally rotates thigh at hip
Rectus Femoris (Quadriceps) (Anterior Thigh)
O: Anterior inferior iliac spine and ilium superior to acetabulum
I: Base of patella and to tibial
tuberosity via patellar ligament
I: Femoral nerve (L2, L3, L4)
B: Profunda femoris and lateral circumflex
femoral arteries
A: Extends leg at knee joint and flexes
thigh at hip joint
Vastus Lateralis (Quadriceps) (Anterior Thigh)
O: Greater trochanter, lateral lip of linea aspera of femur
I: Base of patella and to tibial
tuberosity via patellar ligament
I: Femoral nerve (L2, L3, L4)
B: Lateral circumflex femoral and profunda femoris arteries
A: Extends leg at knee joint
Vastus medialis (quadriceps) (Anterior Thigh)
O: Intertrochanteric line, medial lip of linea aspera of femur
I: Base of patella and to tibial
tuberosity via patellar ligament
I: Femoral nerve (L2, L3, L4)
B: Femoral and profunda
femoris arteries
A: Extends leg at knee joint
Vastus intermedius (quadriceps) (Anterior Thigh)
O: Anterior and lateral surfaces of body of femur
I: Base of patella and to tibial
tuberosity via patellar ligament
I: Femoral nerve (L2, L3, L4)
B: Lateral circumflex femoral and profunda femoris arteries
A: Extends leg at knee joint
Adductor Longus
Medial Thigh
O: Body of pubis inferior to pubic crest
I: Middle third of linea aspera of femur
I: Obturator nerve (anterior division) (L2, L3, L4)
B: Profunda femoris and medial circumflex femoral arteries
A: Adducts thigh at hip
Adductor brevis
Medial Thigh
O: Body and inferior pubic ramus
I: Pectineal line and proximal part of linea aspera of femur
I: Obturator nerve (L2, L3, L4)
B: Profunda femoris, medial
circumflex, femoral, and obturator arteries
A: Adducts thigh at hip, weak hip flexor
Adductor magnus
Medial Thigh
O: Inferior pubic ramus, ramus of ischium
Hamstring part: sciatic nerve (tibial division)
I: Gluteal tuberosity, linea aspera, medial supracondylar line
Hamstring part:
adductor tubercle of femur
I: Adductor part:
obturator nerve (L2, L3, L4)
Hamstring part:
sciatic nerve (tibial division) (L4)
B: Femoral, profunda femoris, and obturator arteries
A: Adductor part: adducts and flexes thigh
Hamstring part: extends thigh
Gracilis
Medial Thigh
O: Body and inferior ramus of pubis
I: Superior part of medial surface of tibia
I: Obturator nerve (L2, L3)
B: Profunda femoris artery, medial circumflex femoral artery
A: Adducts thigh, flexes and medially rotates leg
Obturator Externus
Medial Thigh
O: Margins of obturator foramen, obturator membrane
I: Trochanteric fossa of femur
I: Obturator nerve (L3, L4)
B: Medial circumflex femoral artery, obturator artery
A: Laterally rotates thigh, stabilizes head of femur in acetabulum
Pectineus
Anterior Thigh
O: Superior ramus of pubis
I: Pectineal line of femur
I: Femoral nerve and sometimes obturator nerve
B: Medial circumflex femoral artery, obturator artery
A: Adducts and flexes thigh at hip
Semitendinosus
Posterior Thigh
O: Ischial tuberosity
I: Superior part of medial surface
of tibia
I: Sciatic nerve (tibial division) (L5, S1, S2)
B: Perforating branch of profunda femoris and
medial circumflex femoral arteries
A: Flexes leg, extends thigh
Semimembranosus
Posterior Thigh
O: Ischial tuberosity
I: Posterior part of medial condyle of tibia
I: Sciatic nerve (tibial division) (L5, S1, S2)
B: Perforating branch of profunda femoris and
medial circumflex femoral arteries
A: Flexes leg, extends thigh
Biceps femoris
Posterior Thigh
O: Long head: ischial tuberosity
Short head: Linea aspera and lateral supracondylar line of femur
I: Lateral side of head of fibula
I: Long head:
sciatic nerve (tibial division) (L5–S2)
Short head:
sciatic nerve (common fibular division) (L5, S1, S2)
B: Perforating branches of profunda femoris, inferior gluteal, and medial circumflex femoral arteries
A: Flexes and laterally rotates leg, extends thigh at hip
Psoas major (Iliopsoas) (Anterior Thigh)
O: Transverse processes of lumbar vertebrae, sides of bodies of T12–L5 vertebrae, intervening intervertebral discs
I: Lesser trochanter of femur
I: Ventral rami of first lumbar nerve
B: Lumbar branches of iliolumbar artery
A: Acting superiorly with iliacus, flexes hip; acting inferiorly, flexes vertebral column laterally; used to balance trunk in sitting position; acting inferiorly with iliacus, flexes trunk
Iliacus (Iliopsoas)
Anterior Thigh
O: Superior 2/3 of iliac fossa, iliac crest, ala of sacrum, anterior sacro-iliac ligaments
I: Lesser trochanter of femur and shaft
inferior to it, to psoas major tendon
I: Femoral nerve
B: Iliac branches of iliolumbar artery
A: Flexes thigh at hips and stabilizes hip joint, acts with psoas major
Sartorius (Anterior Thigh)
O: Anterior superior iliac spine and superior part of notch below it
I: Superior part of medial surface of tibia
I: Femoral nerve
B: Femoral artery
A: Abducts, laterally rotates, and flexes thigh;
flexes knee joint
Psoas minor
O: Vertebral margins of T12–L1
vertebrae, corresponding intervertebral disc
I: Pectineal line, iliopectineal
eminence
I: Ventral rami of first lumbar nerve
B: Lumbar branch of iliolumbar artery
A: Flexes pelvis on vertebral column
Quadratus lumborum
O: Medial half of inferior border of 12th
rib, tips of lumbar transverse processes
I: Iliolumbar ligament, internal lip of iliac crest
I: Ventral rami of T12 and first four lumbar nerves
B: Iliolumbar artery
A: Extends and laterally flexes vertebral column, fixes 12th rib during inspiration
