1. Overview:
Leg / Ankle / Foot
In this module, we’ll explore:
The features of the leg & foot
bones
The anatomy of the ankle &
foot joints
The movements possible at the
ankle & foot
The important ligaments of the
ankle & foot
2. Bones of the Leg:
The Tibia & Fibula
3. Features of the Tibia
Features to know:
Medial & Lateral Condyles
Intercondylar Eminence
Tibial Tuberosity
Anterior Crest
Medial Malleolus
Fibular Notch
4. Features of the Fibula
Features to know:
Head
Shaft (proximal,
middle, distal)
Lateral Malleolus
5. Bones of the Foot
The foot has two important
functions:
It supports our body
weight, and
It acts as a lever to propel
the body forward when
we walk and run
The foot includes the tarsal
bones, the metatarsal bones,
and the phalangeal bones
(or toe bones)
6. Bones of the Foot
The Tarsal Bones
The seven tarsal bones form the
posterior half of the foot
1. Talus (“ankle”)
2. Calcaneus ("heel bone")
3. Navicular (medial)
4. Medial Cuneiform (just
distal to Navicular bone)
4
1
2
3
7
5
5. Intermediate Cuneiform
6
6. Lateral Cuneiform
7. Cuboid (lateral)
7. Bones of the Foot
The Metatarsal Bones
The metatarsal bones are
numbered 1 to 5, beginning
on the medial side of the foot
1 2
3 45
The “base” of each metatarsal
is proximal, while the “head”
is distal
The enlarged head of the first
metatarsal forms the "ball of
the foot”
The distal plantar surface of
the first metatarsal rests on
paired sesamoid bones
8. Bones of the Foot
The Phalangeal Bones
There are three phalanges in each
digit, which are identified as:
the proximal phalange
the middle phalange
the distal phalange
The great toe, or hallux, has only
proximal and distal phalanges
As with the metatarsals, the “base” of
each phalange is proximal, while the
“head” is distal
9. Arches of the Foot
The foot has three arches:
1. Medial longitudinal arch
2. Lateral longitudinal arch
3. Transverse arch
These 3 arches form a halfdome that distributes about
half our weight to the heel
bones and half to the heads of
the metatarsals, which
accounts for the foot’s ability
to bear the weight of the body
10. “Fallen Arches”
Fallen Arches (or “flatfeet”) is a condition
that occurs when the arch or instep of the
foot collapses or touches the standing
surface.
Can be structural (you’re born with it) or
functional (you’ve lost it)
Functional flatfeet may result from:
prolonged standing
(esp. if overweight)
running on hard surfaces without
proper arch support
temporary increase in elastin due to
pregnancy
(11) Plantar Fascia
The plantar fascia is a dense
layer of fibrous tissue on the
plantar surface of the foot, which
maintains and stabilizes the
longitudinal arches of the foot
Attaches posteriorly to the
calcaneal tuberosity and
anteriorly to the plantar plates of
the metatarsophalangeal (MTP)
joints and adjacent flexor
tendons of the toes
(12) Windlass Mechanism
The plantar fascia inserts
into the flexor tendons,
and gets pulled taut when
the toe joints are extended
(as when rising onto the
balls of the feet)
As the plantar fascia
becomes more taut, the
height of the arch
increases and creates a
more “rigid” foot
(13) Plantar Fasciitis
Plantar fasciitis is
inflammation of the plantar
fascia, which usually results in
localized pain under the
calcaneous
Sometimes associated with a
rapid gain of weight, but is
also seen in recreational
athletes (especially runners)
Treatment: rest, ice (use
frozen water bottles),
stretching the calf muscles,
orthotics
(14) Tibiofibular Joints
Three tibiofibular joints exist
between the tibia and fibula
1
1. the proximal tibiofibular joint
2. the middle tibiofibular joint
2
3. the distal tibiofibular joint
The tibiofibular joints allow
superior and inferior glide of the
fibula relative to the tibia
3
(15) The Ankle Joint
The ankle joint (aka the
talocrural joint) is located
between the trochlear surface
of the dome of the talus and
the rectangular cavity formed
by the distal end of the tibia
and the malleoli of the tibia
and fibula
The ankle joint resembles a
mortise joint
Classified as a uniaxial,
synovial hinge joint (freely
movable)
(16) Motions of the Ankle Joint
The ankle joint is ideally
capable of 20O of
dorsiflexion and 50O of
plantarflexion
20O
Dorsiflexion
50O
Plantarflexion
These are movements of
the foot at the ankle joint
within the sagittal plane
(around a medialateral
axis)
Reverse action would be
dorsiflexion or
plantarflexion of the leg at
the ankle joint (foot fixed)
(17) Medial Ligaments of the Ankle
Several ligaments fan out
from the medial malleolus
of the tibia to the medial
side of the talus, calcaneus
and navicular bones
Collectively referred to as
the “Deltoid Ligament,”
these ligaments limit
excessive eversion of the
foot at the ankle joint
(18) Lateral Ligaments of the Ankle
The Anterior Talofibular
Ligament (ATL) helps to
prevent excessive
inversion of the ankle joint
The ATL is the most
commonly sprained
ligament in the body
In yoga asana practice, it
is important not to stretch
the ATL by overly
inverting the ankle during
“lotus-like” postures
(19) Other Structures of the Ankle Joint
Bursae and tendon sheaths
are prevalent throughout
the ankle joint, which help
minimize friction between
the tendons and
underlying bony structures
Retinacula help to hold
down the tendons that
cross the ankle joint,
preventing “bowstringing”
of these tendons
(20) Subtalar Tarsal Joint
The subtalar tarsal joint is
the main tarsal joint of the
foot, and is located
between the talus and the
calcaneus
It is classified as a freely
movable, synovial gliding
joint (uniaxial)
(21) Motions Allowed at the Subtalar Joint
Pronation, which is a
combination of:
Eversion
Dorsiflexion
Abduction
Supination, which is a
combination of:
Inversion
Plantarflexion
Adduction
(22) Transverse Tarsal Joint
The transverse tarsal joint
is a compound joint
consisting of:
the talonavicular joint,
between the talus and
navicular bone
the calcaneocuboid joint,
between the calcaneus
and cuboid
It is classified as a freely
movable, synovial gliding
joint
(23) Tarsometatarsal Joints
There are five
tarsometatarsal (TMT)
joints
The 1st thru 3rd TMT
joints are located between
the cuneiforms and the
base of the 1st thru 3rd
metatarsals
Note: The base of the 2nd metatarsal is set back further
posteriorly than the other metatarsals, causing it to be
wedged between the 1st and 3rd cuneiforms; it is
therefore the most stable of the five TMT joints, and an
imaginary line through its corresponding ray is known
as the central stable pillar of the foot
The 4th and 5th TMT joints
are located between the
cuboid and the base of the
4th and 5th metatarsals
(24) Intermetatarsal Joints
All five metatarsal bones
articulate with each other
proximally (at their bases)
and distally (at their
heads)
All are freely movable,
gliding synovial joints
Allow non-axial
gliding motion of one
metatarsal relative to
the adjacent metatarsal
(25) Metatarsophalangeal Joints
The metatarsophalangeal
(MTP) joints are located
between the heads of the
metatarsals and the bases
of the proximal phalanges
of the toes
They are classified as
freely movable, synovial
condyloid joints (biaxial)
(26) Motions of MTP Joints
The major motions allowed are:
Abduction/Adduction
within the transverse plane
around a vertical axis
Flexion/Extension within the
sagittal plane around a
mediolateral axis
Average ROM is:
Toes #2-5: Flexion
(40O)/Extension (60O)
Big Toe: Flexion (40O)/
Extension (80O)
(27) Interphalangeal Joints
The IP joints of the foot are
located between the head of the
more proximal phalanx and the
base of the more distal phalanx
The big toe has one IP joint
between the proximal and
distal phalanges of the big toe
Toes #2-5 have two IP joints – a
proximal IP joint (PIP) between
the proximal and middle
phalanges, and a distal IP joint
(DIP) between the middle and
distal phalanges
Allow flexion/extension within
sagittal plane