The ankle joint is a modified hinge joint formed between the lower ends of the tibia and fibula bones above and the talus bone below. It allows for dorsiflexion and plantarflexion movements. Key ligaments like the deltoid ligament and anterior/posterior talofibular ligaments provide stability. Muscles like the gastrocnemius and soleus facilitate plantarflexion while the tibialis anterior enables dorsiflexion. Injuries commonly involve ligament sprains or fractures of the malleoli bones.

1. ANKLE JOINT
DR. SUNDIP CHARMODE
ASSOCIATE PROFESSOR
DEPARTMENT OF ANATOMY
AIIMS RAJKOT

2. INTRODUCTION
• The ankle joint is a uni-
axial synovial joint.
• Transverse axis with an
inclination laterally, it is
modified hinge joint.
• Talo-crural joint

3. BONES FORMING THE JOINTS
1. Lower end of Tibia
2. Lower end of Fibula
3. Talus
4. Calcaneum

6. BONES FORMING THE JOINTS
• Above: Inferior surface of lower end of tibia with its medial malleolus
and lateral malleolus of fibula (articular surfaces of both bones form a
Tibio-fibular Mortise)
• Below: Trochlear surface of the body of talus with comma shaped
facet for tibial malleolus and triangular shaped facet for lateral
malleolus (Trochlea Tali)

9. TROCLEA TALI
• The upper surface of the
talus is convex from before
backward and gently
concave from side to side.
• It is broader in the anterior
part.

11. LIGAMENTS OF THE JOINTS
1. Capsular ligament along with synovial membrane
2. Medially: Deltoid ligament
3. Laterally:
1. Anterior and posterior Talo-fibular ligaments
2. Calcaneo-fibular ligaments

12. CAPSULAR LIGAMENT
• The fibrous capsule envelops the joint completely.
• Thin in front and behind
• Thickened on sides, where it blends with the collateral ligaments
• Attachments:
• Above: Bones of the tibio-fibular mortise close to the periphery of the
articular surface
• Below: Peripheral margin of the trochlea tali, but in anterior part it extends to
the dorsal surface of the neck of the talus.

15. SYNOVIAL MEMBRANE
• Lines the inner surface of the fibrous capsule but ceases at the
periphery of the articular cartilage.
• A small synovial recess extends upward in the inferior tibio-fibular
syndesmosis.

16. DELTOID/MEDIAL LIGAMENT
• It is a strong triangular band which blends with the fibrous capsule,
and it consist of superficial and deep parts.
• Superficial part:
• Apex: attached above to the tip and the adjoining margins of the
tibial malleolus
• Anterior part: passes downward and forwards and is attached to the
tuberosity of the navicular bone and blends with the medial margin
of the spring ligament or plantar calcaneo-navicular ligament

18. DELTOID/MEDIAL LIGAMENT
• Intermediate part: extends
vertically downward and is attached
along the medial surface of
sustentaculum tali of calcaneus
(tibio-calcanean part)
• Posterior part: Extends downward
and backward and gains
attachment to the medial tubercle
of talus (Posterior tibio-talar part)

20. DELTOID/MEDIAL LIGAMENT
• Deep part: It connects a
depression close to the tip of
tibial malleolus to the non-
articular part of the medial
surface of talus below the
comma shaped facet. (Anterior
tibio-talar part)

21. LATERAL LIGAMENT
1. Anterior Talo-fibular:
2. Posterior Talo-fibular:
3. Calcaneo-fibular:

23. ANTERIOR TALO-FIBULAR LIGAMENT
• Weak band, extends forward
and medially from the anterior
margin of fibular malleolus to
the adjacent lateral surface of
neck of talus.

24. POSTERIOR TALO-FIBULAR LIGAMENT
• It extends backward and
medially from the posterior
margin of the fibular
malleolus to the posterior
tubercle of talus.

25. CALCANEO-FIBULAR LIGAMENT
• It extends downward and
backward as a fibrous cord
from a notch near the tip of
fibular malleolus to an
elevation on the lateral surface
of the calcaneum.

26. MOVEMENTS AND MECHANISM
• In symmetrical standing, the line of gravity passes slightly in front of
the centre of ankle joint, leading to forward dislocation of leg bones
from talus.
• This is prevented by bones and muscles.
• The broad anterior part of the trochlear surface of talus and the tonic
contraction of triceps surae through the tendo-calcaneus nullify the
forward dislocation.

27. MOVEMENTS AND MECHANISM
• Active movements permitted at ankle joint: Dorsiflexion and
Plantarflexion
• Dorsiflexion: range – 10 degrees and when assisted by tarsal joints it
may increase to 20 degrees
• Plantarflexion: range – 20 degrees and when assisted by tarsal joints
it may increase to 40 degrees

28. DORSIFLEXION
• The wider anterior part of
the trochlear surface of talus
comes in contact with the
tibio-fibular mortise

29. DORSI FLEXION/ PLANTAR FLEXION

30. MUSCLES PRODUCING MOVEMENTS

31. MUSCLES PRODUCING MOVEMENTS
• Peroneus tertius and peroneus longus come into play in extreme
plantar flexion.
• Gastrocnemius initiates plantar flexion since it is white muscle and
soleus maintains it since it is a red muscle.

32. RELATIONS OF ANKLE JOINT
• In front: from medial to
lateral side the structures are:
1. Tendon of tibialis anterior
2. Extensor hallucis longus
3. Anterior tibial vessels
4. Deep peroneal nerve
5. Tendons of EDL
6. Peroneus tertius

33. RELATIONS OF ANKLE JOINT
• Behind: Tendo-calcaneus in
middle, separated from the joint by
fibro-fatty tissue:
• Behind tibial malleolus: (from
medial to lateral):
• Tendon of tibialis posterior
• Flexor digitorum longus
• Posterior tibial vessels
• Tibial nerve
• Tendon of FHL
• Behind fibular malleolus:
• Tendon of peroneus brevis and
peroneus longus

35. ARTERIAL SUPPLY
• The joint is supplied by malleolar branches of the anterior tibial
and posterior tibial arteries.

36. NERVE SUPPLY
• Branches from the deep peroneal and tibial nerves.
• Ankle centre is located in the L4, L5 ,S1and S2 segments of spinal
cord.
• L4 and L5 segments control dorsiflexion
• S1 and S2 segments control plantar flexion

37. CLINICAL CORRELATES
1. Injuries of ankle joint are usually caused by falls or twists.
2. Ankle sprain: due to over inversion is common
3. The anterior talo-fibular and calcaneo-fibular ligaments are
sometime torn and in severe cases the anterior part of capsule is
ruptured.
4. Forcible eversion leads to tear of deltoid ligament or avulsion
fracture of medial malleolus

38. CLINICAL CORRELATES
5. Association of horizontal fracture of medial malleolus and
oblique fracture of fibular shaft is known as Pott’s fracture
6. Dislocation of the ankle joint is very uncommon.

39. THANK YOU