Lab 6 Anatomy of leg and foot.
The tibia is the major weight-bearing bone in the leg. Move your hands anterior and inferior to a
prominent bump called the tibial tuberosity. It is just inferior to the patella and acts as a
common attachment for the quadriceps femoris muscles of the anterior thigh. The medial
malleolus is the medial and distal portion of the tibia. The fibula is thinner and lateral to the tibia.
It is considered a non-weight-bearing bone. The proximal fibula head is a site of muscle
attachment. The distal end of the fibula terminates at the lateral malleolus. The talus sits in
between both malleoli.
The foot and ankle are made up of 26 bones, held together by many ligaments (Figure 8.12).
The foot is divided into 3 distinct areas. The hindfoot (calcaneus and talus) connects the foot to
the lower leg. Dorsi and plantar flexion result from the gliding of the tibia over the talus. The
midfoot includes the cuboid, navicular, and the 3 cuneiform bones (medial, intermediate, and
lateral). It forms the arches of the foot, which function in shock absorption during gait. These 7
bones are sometimes referred to as the tarsal bones (tarsus). The forefoot consists of the
remaining long bones of the foot (5 metatarsals, 5 proximal, 4 middle, and 5 distal phalanges).
Notice the first metatarsal is much larger than the others. The size of this bone reflects its
importance in weight bearing, especially during walking. Toes 2–5 are composed of 3 separate
phalangeal bones while the first toe is only composed of 2 phalangeal bones (no middle phalanx).
Key Muscles and Nerve Innervation
gastrocnemius
soleus
plantaris
popliteus
flexor hallucis longus
flexor digitorum longus
tibialis posterior
peroneus (fibularis) longus
peroneus (fibularis) brevis
quadratus lumorum
tibialis anterior
extensor hallucis longus
extensor digitorum longus
peroneus tertius
tibial (S1,2)
tibial (S1,2)
tibial (L4,5 S1)
tibial (L4,5, S1)
tibial
(L5,S1.2)
tibial (L5, S1)
tibial (L5, S1)
superficial peroneal (L4,5, S1)
superficial peroneal (L4,5, S1)
T12, L1
deep peroneal (L4,5, S1)
deep peroneal (L4,5, S1)
deep peroneal (L4,5, S1)
deep peroneal (L4,5, S1)
The Leg and Ankle
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2.3.1 Introduction to the leg and ankle (1:19)
2.3.2 Bones and ligaments of the ankle joint (4:14)
2.3.3 Bones and ligaments of the hindfoot (4:55)
2.3.4 Pulley-like structures around the ankle joint (1:40)
2.3.5 Review of bones, joints, and ligaments of the ankle region
(1:46)
2.3.6 Ankle extensor and flexor muscles (5:20)
2.3.7 Fascial compartments of the leg (3:40)
2.3.8 Foot evertor and invertor muscles (4:08)
2.3.9 Review of muscles that move the ankle and foot (1:19)
2.3.11 Nerves of the leg and ankle (2:31)
2.3.12 Review of blood vessels and nerves of the leg and ankle (1:12)
The Foot
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2.4.1 Bones of the midfoot, forefoot, and toes (2:49)
2.4.2 Main ligaments supporting the arches of the foot (2:28)
2.4.3 Plantar aponeurosis and metatarsophalangeal joints (4:14)
2.4.4 Review of bones, joints, and ligaments of the foot (1:00)
2.4.5 Long and short toe extensor muscles (3:24)
2.4.6 Long toe flexor muscles (2:38)
2.4.7 Short toe flexor muscle groups (3:14)
2.4.8 Short flexor muscles of the great and fifth toes (3:00)
2.4.9 Overview of short plantar muscles (1:57)
2.4.10 Review of muscles of the foot (1:15)
2.4.12 Nerves of the foot (4:01)
2.4.13 Review of blood vessels and nerves of the foot (0:53)
2.4.14 Skin of the foot (0:50)
Tarsals
 Talus, calcaneus, navicular, first cuneiform, second cuneiform, third
cuneiform, and cuboid
Metatarsals: Base, Shaft, Head
Phalanges:
distal, middle, and proximal.
1. Gastrocnemius
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
2. Soleus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
3. Plantaris
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
4. Popliteus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
5. Flexor hallucis longus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
6. Flexor digitorum longus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
7. Tibialis posterior
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
8. Peroneus (fibularis) longus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
9. Peroneus (fibularis) brevis
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
10. Tibialis anterior
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
11. Extensor hallucis longus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
12. Extensor digitorum longus
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
13. Peroneus tertius
a.
b.
c.
d.
Origin:
Insertion:
Nerve innervation:
Action:
\
Dermatomes and Peripheral Nerves of the Lower Extremity
Nerves of the Lower Extremity
Nerve
Sciatic nerve
Common fibular
(peroneal)
Superficial fibular
Deep fibular
Tibial
Superior Gluteal
Inferior Gluteal
Plantar
Femoral
Obturator
Saphenous
Posterior cutaneous
Femoral
Lateral and anterior
Femoral cutaneous
Sural
Nerve Root Level
Muscles Innervated and
Sensory Area Innervated