The ankle joint is a hinge joint that connects the lower leg bones (tibia and fibula) to the foot bone (talus). It is stabilized by strong ligaments including the deltoid ligament medially and the anterior talofibular, calcaneofibular, and posterior talofibular ligaments laterally. The ankle joint allows for two motions: dorsiflexion and plantar flexion powered by various muscles to point the toes up or down. Common injuries include ankle sprains from excessive inversion or eversion stretching the ligaments.
2. TYPE
It is a synovial joint of hinge variety. The
shape of articulating bones, strength of the
ligaments and the surrounding tendons make
this joint strong and stable.
4. Articular surfaces of ankle joints
PROXIMAL ARTICULAR SURFACE 1.the lower end of tibia, including its
medial malleolus 2.lateral malleolus 3. inferior transverse tibiofibular
ligament.
DISTAL ARTICULAR SURFACE body of talus.
The socket is formed by proximal articular surface into which the body
of talus fits, is deepened by the inferior transverse tibiofibular ligament
k/a deep tibiofibular socket or tibiofibular mortise
7. Fibrous capsule is
attached all around
articular margins with
two exceptions.
Posterosuperiorly it is
attached to inferior
transverse tibiofibular
ligament.
Anteroinferiorly it is
aatached to the dorsum of
neck of talus.
8. .
Medial Ligament: Also known as deltoid ligament
This is located on the medial aspect of the foot. It is
the largest ligament but is actually comprised of
several sections all fused together. This ligament
prevents (eversion) of the ankle. The deltoid ligament
is triangular in shape
Divided into two parts: superficial and deep
Above : both parts are attached to the apex and
margins of the medial malleolus.
Below it has two places of attachment.
.
10. Superficial part : its fibers are divided into three
parts:
ANTERIOR FIBERS (Tibionavicular )
MIDDLE FIBERS (Tibiocalcaneal )
POSTERIOR FIBERS(Posterior tibiotalar )
The deep part: (Anterior tibiotalar) are attached
to the anterior part of medial surface of talus
12. Lateral ligament: It consists of
three bands
Anterior talofibular ligament:
It runs from the ant. margin of
lateral malleolus to the neck of
talus.
Calcaneofibular ligament: It
runs from the tip of lateral
malleolus to lateral surface of
calcaneum.
Posterior talofibular
ligament:
It runs from the lateral malleolus
to the posterior tubercle of the
talus
14. Anterior relations:
Tibialis anterior, Extensor Hallucis longus,
Anterior tibial vessels, deep peroneal nerve,
Extensor digitorum longus, Peroneus tertius
Pneumonic Tall Himalayas Are Never Dry
Places
15. Posterior relations:
Tibialis posterior, Flexor digitorum
longus, posterior tibial vessels, tibial
nerve, flexor hallucis longus
Pneumonic Tom Dick And Not Harry
16. Blood supply of ankle joint:
The ankle joint receives its blood supply form
malleolar branches of the anterior and posterior tibial
and peroneal arteries.
Nerve supply to ankle joint:
The ankle joint receives its nerve supply from deep
peroneal and tibial nerves. Occasionally, the
superficial peroneal nerve also supplies the ankle
joint.
17. Movements of ankle joint
As the ankle joint is a uniaxial hinge joint permitting only two
types of movements: Dorsiflexion and Plantar flexion.
Dorsiflexion: It is the movement in which the dorsal surface
of foot is flexed. In this movement the toes point upward.
Muscles responsible for it include;
Tibialis anterior
Extensor hallusiclongus
Extensor digitorumlongus
Peroneus tertius
Ankle joint is most stable in dorsiflexion
18. Plantar flexion: It is the movement of foot in which
its plantar surface is flexed. The toes point downward
in this movement. Muscles responsible for plantar
flexion include;
Gastrocnemius
Soleus
Plantaris
Tibialis posterior
Flexor digitorumlongus
Flexor hallucislongus.
The joint is unstable in plantar flexion
21. Ankle sprain most common.Occurs due to
stretching & tearing of the ligaments.
When plantar flexed foot is excessively
inverted.Lateral ligament is stretched &
torn (anterior talofibular ligament most
commonly torn).
When plantar flexed foot is excessively
everted deltoid ligament is not torn,
instead there is avulsion # of med
malleolus.
24. # of Malleoli Potts fracture-
Occurs when foot is everted forcefully.
Oblique fracture of lateral malleolus
due to internal rotation of tibia.
Transverse fracture of medial
malleolus due to pull by strong deltoid
ligament
Fracture of posterior margin of lower
end of tibia(3rd malleolus)
26. Dislocation of the
ankle joint:-
Very uncommon.
If it occurs, it is
accompanied by
the # one malleoli.