Muscles of the Foot
and Lower Leg
Mr. Brewer
Movements
• There are 6 major movements that take place
in the lower leg to the foot.
• What are they?
Movements
• The 6 Major Movements that occur at the
ankle and foot are:
– Plantar Flexion
– Dorsi Flexion
– Inversion
– Eversion
– Toe Flexion
– Toe Extension
Plantar Flexion
• Gastrocnemius:
– The gastrocnemius is the
prime mover for plantar
flexion.
– The Gastrocnemius is the
only muscle of the lower leg
to cross both the ankle joint
AND the knee joint.
– In combination with the
soleus, these muscles are
referred to as the “calf”
muscles.
Plantar Flexion
- Soleus:
- The soleus is located directly under
the gastrocnemius.
- It is also responsible for plantar
flexion, although it acts as an
assistant mover with the
gastrocnemius for plantar flexion.
- Both the Gastrocnemius and Soleus
have a distal attachment to the
Achilles Tendon.
- The Achilles tendon then inserts
into the proximal aspect of the
calcaneous at it’s most posterior
location.
Plantar Flexion
• Just like most muscles in the body, there are several
muscles that contribute to plantar flexion as “assistant
movers”.
• Most of these muscles are responsible for multiple
movements around the joint they are located.
• Some additional muscles that also play a role in plantar
flexion along with other movement(I.E. Plantar-flexion
and eversion):
–
–
–
–
–
Peroneus Longus
Peroneus Brevis
Flexor Digitorum Longus
Flexor Hallicus longus
Tibialis Posterior
Dorsi-Flexion
• Tibialis Anterior –
– Located on the lateral
aspect of the tibia.
– Attaches distally to the
mid-foot to dorsi-flex the
foot.
– Also is responsible for
inversion of the foot.
Dorsi-Flexion
There are 3 additional muscles that play a role in
dorsi-flexion, yet they have other primary
movements that they are responsible for.
Muscles:
- Extensor
Digitorum
Longus
- Peroneus Tertius
- Extensor Hallucis
Longus
Inversion
• Inversion is the act of a
movement in which the
plantar surface (sole) of
the foot rotates towards
the mid-line of the body.
• There are 2 major
muscles that are
responsible for this
action.
Inversion
• Tibialis Posterior :
– Primarily responsible
for Inversion of the
foot.
– Also plays a minor role
in plantar flexion.
– The other muscle that
assists in inversion of
the ankle is the Tibialis
Anterior.
Eversion
Eversion is the act of a movement
in which the plantar surface (sole)
of the foot rotates towards the
lateral aspect of the body.
There is a group of 3 muscles that
are primarily responsible for
eversion of the foot.
Because of the boney and
ligament anatomy of the foot,
eversion ROM is very limited.
(Mostly because of the deltoid
ligament)
* ROM = Range of Motion (measured in degrees)
Eversion
• The peroneal muscles are
all located on the lateral
side of the lower leg, and
are primarily responsible
for eversion.
• The peroneal muscles are
also known as “fibularis”.
(I.E. Fibularis Longus,
Brevis and Tertius)
• The Peroneal Muscles:
– Peroneus Longus
– Peroneus Brevis
– Peroneus Tertius
Toe Flexion
• Toe Flexion is the act of
curling your toes towards the
plantar surface (ground)
• The 2 muscles that are
primarily responsible for toe
flexion are called:
– Flexor Digitorum Longus
– Flexor Hallucis Longus
Toe Flexion
• Flexor Digitorum Longus:
– This muscle is the flexor
muscle that flexes all 4
lateral toes of the foot.
• Flexor Hallucis Longus:
– Hallux is the Latin term for
the great toe.
– The Flexor Hallucis Longus’
primary responsibility is to
flex the great toe.
Toe Extension
• Toe Extension is
virtually the opposite
of Toe Flexion.
• Both in the action of
the muscles, and in
the naming of the
muscles.
Toe Extension
• Extensor Digitorum
Longus:
– The extensor digitorum
longus is responsible for
extending the lateral 4 toes
towards the dorsal surface
(up).
• Extensor Hallucis Longus:
– The extensor digitorum
longus is responsible for
extending the great toe
towards the dorsal surface
(up).
Review
1. What group of muscles is responsible for
eversion of the foot?
2. Lifting your heals off of the ground and
“standing on your toes” is an example of what
ankle movement?
3. What is the only muscle of the lower leg that
crosses both the ankle joint and the knee joint.
4. Hallux is Latin for what?
5. The tibialis ___________ is primarily responsible
for ankle dorsi-flexion.
Review Answers
1.
2.
3.
4.
5.
The Peroneals(Fibularis)
Plantar-flexion
The Gastrocnemius
The Great Toe
Anterior