Download 25-Ankle joint & tarsal

Ankle Joint
It consists of a deep socket formed by
the lower end of the tibia & fibula , into
which is fitted the upper part of the body
of the talus .
The talus is able to move on a
transverse axis in a hingelike manner.
The shape of the bones & the strength of
the ligaments and the surrounding
tendons make this joint strong and stable
Articulation
It is between the lower end of the tibia &
the 2 malleoli and the body of the talus.
The articular surfaces are covered by
hyaline cartilage.
The inferior transverse tibiofibular
ligament , which runs between the lateral
malleolus and the posterior border of the
lower end of the tibia ,deepens the
socket into which the body of the talus
fits.
Ankle Joint
Type : it is a synovial hinge joint
Capsule: It is attached to the bones
near their articular margins & it
encloses the joint .
Ligaments
The lateral ligament
It is week than medial ligament and
consists of 3 bands .
1- The anterior talofibular ligament
it runs from the lateral malleolus to the
lateral surface of the talus.
2- The calcaneofibular ligament
it runs from the tip of the lateral
malleolus downward and backward to
the lateral surface of the calcaneum.
3- the posterior talofibular ligament
it runs from the lateral malleolus to the
posterior tubercle of the talus .
tibiofibular
talofibular
The medial or deltoid ligament
It is strong and is attached to the tip of the medial
malleolus.
Its deep fibers are attached to the nonarticular
area on the medial surface of the body of the talus.
Its superficial fibers are attached to the medial
side of the talus , the sustentaculum tali , the
plantar calcaneonavicular ligament ( spring ) and
the tuberosity of the navicular bone.
Ankle Joint
Synovial Membrane : It lines the capsule.
Nerve Supply : Deep peroneal & tibial nerves
Movements: Dorsiflexion & plantar flexion .
N. B. inversion & eversion tack place at the
tarsal joints .
Dorsiflexion is performed by the tibialis
anterior , extensor hallucis longus, extensor
digitorum longus, and peroneus tertius.
It is limited by the tension of the
tendocalcaneus , the posterior fibers of the
medial ligament and the calcaneofibular
ligament.
During dorsiflexion the wider anterior part of
the articular surface of the talus is forced
between the medial & lateral malleolus,
causing them to separate slightly & tighten
the ligaments of the distal tibiofibular joint.
This arrangement increases the stability of
the ankle joint when the foot is in the initial
position for major thrusting movements in
running , jumping and walk .
Tibiofibular
Talofibular
Plantar flexion is performed by the
gastrocnemius, soleus,plantaris, peroneus
longus & brevis , tibialis posterior, flexor
digitorum longus and flexor hallucis longus
It is limited by the tension of the opposing
muscles , the anterior fibers of the medial
ligament and the anterior talofibular
ligament .
When the ankle is fully plantar flexed, the
ligaments of the distal tibiofibular joint are
less taut and small amounts of rotation ,
abduction & adduction are possible.
Important Relations
anteriorly : tibialis anterior , extensor
hallucis longus ,anterior tibial vessels,
deep peroneal nerve, extensor digitorum
longus and peroneus tertius.
Posteriorly : tendo calcaneus & plantaris.
Posterolaterally: peroneus longus& brevis
posteromedially: tibialis posterior, flexor
digitorum longus, posterior tibial vessels
,tibial nerve and flexor hallucis longus
Tarsal joints
1- Subtalar joint
It is between the inferior surface of the body
of the talus and the facet on the middle of
the upper surface of the calcaneum.
2- Talocalcaneonavicular joint
It is between the rounded head of the talus ,
the upper surface of the sustentaculum tali
and the posterior concave surface of the
navicular bone.
3- Calcaneocuboid joint
It is between the anterior end of the
calcaneum & the posterior surface of the
cuboid .
The talocalcaneonavicular & calcaneocuboid joints are together referred as
midtarsal or transverse tarsal joints .
N.B. The inversion & eversion movements
take place at the 3 previous joints .