Download Chapter 12, Part 2

Chapter 12, Part 2
Appendicular Muscles
Legs and Hips
Fig. 12.15a
Psoas
minor
Iliac crest
Psoas major
Gluteus medius
Iliacus
Gluteus maximus
Tensor fasciae latae
Sartorius
Iliopsoas
Pectineus
Adductor
brevis
Rectus femoris
Adductor
longus
Gracilis
Vastus
lateralis
Iliotibial tract
Adductor
magnus
Biceps femoris,
long head
Semimembranosus
Patella
Biceps femoris, short head
Gastrocnemius
(a) Right thigh, anterior view
(b) Right thigh, lateral view
Fig. 12.15b
Iliac crest
Sacrum
Gluteus maximus (cut)
Piriformis
Superior gemellus
Obturator internus
Sacrotuberous ligament
Inferior gemellus
Ischial tuberosity
Gluteus medius (cut)
Gluteus minimus
Gluteus medius (cut)
Gluteus maximus (cut)
Quadratus femoris
Gracilis
Biceps femoris, long head
Adductor magnus
Semitendinosus
Iliotibial tract
Fig. 12.16
View of
cross
section
Lateral thigh and
some gluteal
muscles abduct
the thigh.
Anterior
Femur
Lateral
Posterior
thigh muscles
extend the thigh
and/or flex the
leg/knee.
Anterior thigh
muscles
flex the hip and/or
Medial extend the leg/knee.
Medial thigh
muscles adduct
the thigh.
Posterior
Fig. 12.17
(a) Right thigh, anterior view
• Most muscles that move the thigh originate
on the os coxae and insert on the femur
• Hip flexors insert on anterior femur and flex
thigh
• Psoas major originates on vertebrae, iliacus
originates on iliac fossa; both fuse into
iliopsoas that inserts on femur
• Sartorius originates on ASIS, inserts on tibial
tuberosity; crosses thigh, assists with hip
flexion; medially rotates leg
Iliacus
Psoas major
Iliopsoas
Sartorius
Fig. 12.15a
• Hip adductors are medial on thigh
• Adductor longus, adductor brevis,
gracilis, and pectineus also flex thigh
• Adductor magnus also extends and
laterally rotates thigh
(a) Right thigh,
anterior view
Pectineus
Adductor
brevis
Adductor
longus
Gracilis
Adductor
magnus
• originates on pubis and ischial tuberosity,
inserts on medial femur
Fig. 12.15a
(b) Right thigh, lateral view
• Tensor fasciae latae is small
muscle that attaches to lateral
thickening of fascia lata called
iliotibial tract
Iliac crest
Tensor fasciae latae
Gluteus
maximus
Iliotibial
tract
Sartorius
• Gluteus muscles extend
thigh
• Gluteus medius and
minimus also abduct and
medially rotate thigh
Iliac crest
Sacrum
Gluteus
maximus
(cut)
Iliac crest
Gluteus medius
Gluteus maximus
Fig. 12.15b
Gluteus medius (cut)
Gluteus minimus
Gluteus medius (cut)
Gluteus
maximus
(cut)
Fig. 12.15b
• Muscles deep to
gluteal muscles
laterally rotate thigh
and hip joint
•
•
•
•
Piriformis
Superior gemellus
Obturator internus
Inferior gemellus
Iliac crest
Sacrum
Gluteus
maximus (cut)
Piriformis
Superior
gemellus
Obturator internus
Inferior gemellus
Ischial tuberosity
Gracilis
Adductor magnus
Gluteus medius (cut)
Gluteus minimus
Gluteus
medius (cut)
Gluteus
maximus
(cut)
Quadratus
femoris
Iliotibial tract
Iliac crest Fig. 12.18
Gluteus medius
Gluteus maximus
Adductor magnus
Gracilis
Iliotibial tract
Semitendinosus
Biceps femoris,
long head
Biceps femoris,
short head
(a) Right thigh, posterior view
• Hamstrings are on back of thigh
• Extend thigh and flex knee
• Have common origin on ischial
tuberosity; insert separately on leg
• Biceps femoris inserts on head of
fibula
• Semitendinosus inserts on proximal
medial tibia
• Semimembranosus (deep to biceps
femoris) inserts on posterior surface of
medial condyle of tibia
Fig. 12.18
(b) Thigh extensors
Ischial tuberosity
Linea aspera
Semitendinosus
Biceps femoris,
long head
Semimembranosus
Adductor
magnus
Biceps
femoris,
short head
Head of fibula
Quadriceps
group
• Located on front of thigh
• Extends the knee joint
Fig. 12.17
Greater trochanter
Rectus femoris
Vastus lateralis
Vastus intermedius
(deep to rectus
femoris)
Sartorius
Patella
Patellar ligament
Tibia
(b) Anterior thigh muscles
Vastus
medialis
Fig. 12.19
Anterior
Anterior leg muscles
dorsiflex the foot and/or
extend the toes.
View of
cross
section
Posterior leg
muscles flex the
leg, plantar flex the
foot, and/or flex
the toes.
Lateral
Lateral leg muscles
plantar flex and
evert the foot.
Posterior
(a) Right leg, anterior view
Fig. 12.20
• Crural muscles move
ankle, foot, and toes
(some also help flex leg)
Gastrocnemius
Fibularis
longus
Fibularis
brevis
Extensor
digitorum
longus
Fibularis
tertius
tendon
Extensor
digitorum
brevis
Tibia
Tibialis anterior
Extensor hallucis longus
Extensor retinaculum
Extensor hallucis longus tendon
Extensor digitorum
longus tendons
Extensor hallucis brevis
• Extensor digitorum longus
flexes foot and extends toes
(a) Right leg, anterior view
• Fibularis tertius tendon extends
from muscle to evert foot
• Extensor hallucis longus
dorsiflexes foot and extends big
toe
• Tibialis anterior is primary
dorsiflexor of foot, also inverts
foot
• inserts on medial plantar side of
foot
• Tendons of these muscles
pass through extensor
retinaculum at ankle
Fig. 12.20
Tibia
Fibularis
brevis
Extensor
digitorum
longus
Fibularis
tertius
tendon
Tibialis anterior
Extensor hallucis longus
Extensor retinaculum
Extensor hallucis longus tendon
Extensor digitorum
longus tendons
(a) Right leg, anterior view
Fig. 12.20
• Crural muscles move
ankle, foot, and toes
(some also help flex leg)
Gastrocnemius
Fibularis
longus
Fibularis
brevis
Extensor
digitorum
longus
Fibularis
tertius
tendon
Extensor
digitorum
brevis
Tibia
Tibialis anterior
Extensor hallucis longus
Extensor retinaculum
Extensor hallucis longus tendon
Extensor digitorum
longus tendons
Extensor hallucis brevis
(b) Anterior leg muscles
Fig. 12.20
Tibialis
anterior
Extensor
digitorum
longus
Fibularis
tertius
Fibularis
tertius
tendon
Extensor
hallucis
longus
(b) Lateral leg muscles
Fig. 12.21
Gastrocnemius
Tibialis anterior
Fibularis longus
Fibularis
longus
Fibularis
brevis
Fibularis brevis
Fibularis longus tendon
5th metatarsal
Fig. 12.21
Patella
Head of fibula
Gastrocnemius
Soleus
Fibularis
longus
Fibularis
brevis
Fibularis tertius
Calcaneal tendon
Extensor digitorum brevis
Tibialis anterior
Extensor digitorum
longus
Extensor hallucis longus
Extensor retinaculum
Extensor hallucis brevis
Extensor hallucis longus tendon
Fibular retinaculum
Fibularis tertius
tendon
(a) Right leg, lateral view
Extensor digitorum
longus tendons
5th metatarsal
• Posterior compartment muscles
plantar flex foot
• Gastrocnemius has two bellies
Fig. 12.22
Plantaris
• flexes leg and plantar flexes foot
• Soleus is deep to gastrocnemius,
resembles flat fish
• plantar flexes foot
• Gastrocnemius and soleus have
common tendon, calcaneal
tendon or Achilles tendon
• Plantaris (absent in some
people) is weak leg flexor
Gastrocnemius
Lateral
head
Medial
head
Soleus
Calcaneal tendon
(a) Right leg, superficial poster
(b) Deep posterior view
Fig. 12.22
Plantaris (cut)
Gastrocnemius (cut)
Popliteus
Tibialis posterior
Fibularis longus
Flexor digitorum longus
Flexor hallucis longus
Fibularis brevis
Calcaneal tendon (cut)
• Popliteus rotates tibia slightly to unlock
fully extended knee
• Tibialis posterior is deep to soleus
• plantar flexes and inverts foot
• Flexor digitorum longus attaches to distal
phalanges of toes 2-5
• plantar flexes foot, flexes MP, PIP, and DIP
joints of toes 2-5
• Flexor hallucis longus attaches to distal
phalanx of big toe
• plantar flexes foot and flexes big toe
Fig. 12.22
Tibia
Popliteus
Tibialis
posterior
Fibula
Flexor
digitorum
longus
Interosseous
membrane
Tarsal and
metatarsal
bones
Distal
phalanges of
toes 2–5
(c) Deep posterior leg muscles
Flexor
hallucis
longus
Distal
phalanx
of hallux
Fig. 12.23
• Lumbricals
flex MP
joints and
extend DIP
and PIP
joints
Flexor digitorum
brevis
Abductor hallucis
Abductor digiti
minimi
Adductor
hallucis
Lumbricals
Flexor hallucis brevis
Flexor digiti minimi brevis
Tendon of flexor
hallucis longus
Tendons of flexor
digitorum longus
Quadratus plantae
Abductor digiti minimi (cut)
Abductor hallucis (cut)
Calcaneus
(a) Layer 1 (superficial)
(b) Layer 2 (deep)
(c) Layer 3 (deeper)
(e) Layer 4 (deepest),
dorsal view
Fig. 12.23
(d) Layer 4
(deepest),
plantar view
Plantar interossei
Dorsal interossei
• Dorsal interossei
abduct toes
• Plantar interossei
adduct toes