Ankle and foot anatomy Flashcards
Which bones form the ankle joint?
Tibia
Fibula
Talus
What are the tibia and fibula joined together by?
Tibiofibiular ligaments
What structure do the tibia and fibula form when they are joined together by the tibiofibular ligaments?
Mortise
What shape is the articulating part of the talus?
Wedge shaped (broad anteriorly, narrow posteriorly)
Which part of the talus fits into the mortise?
The body of the talus
Describe the position of the talus in dorsiflexion
Anterior part is in mortise (joint is more stable)
Describe the position of the talus in planter flexion
Posterior part of talus is in mortise (joint is less stable)
What are the weight bearing surfaces of the ankle joint?
Talus and tibia
What are the stabilising ligaments of the ankle?
Medial (deltoid) and lateral
How many ligaments form the deltoid (medial) ligament?
4
What is the main function of the deltoid (medial) ligament?
Resists over-eversion of the foot
How many ligaments in the lateral ligament made up of?
3
What are the 3 ligaments that form the lateral ligament?
Anterior talofibular
Posterior talofibular
Calcaneofibular
What is the function of the lateral ligament?
Over-inversion of the foot
F
Fractures of the ankle can often be associated with what?
Ligament damage (due to ankle joint being a ‘ring’ shape in the coronal plane)
What type fo joint is the ankle joint?
Hinge synovial joint
What are the 4 movements that can occur in the ankle joint?
Dorsiflexion
Plantarflexion
Inversion
Eversion
Which muscles allow for ankle dorsiflexion?
Anterior compartment of the leg:
Tibialis anterior
Extensor hallucis longus
Extensors digitorum longus
Which muscles allow for ankle plantar flexion?
Posterior compartment of leg:
Gastrocnemius
Soleus
Plantaris
Posterior tibialis
How does a lateral ankle sprain often happen?
Excessive inversion of a plantar flexed, weight-bearing foot
Why is the lateral ligament more likely to be damaged?
Weaker
Resists inversion
Which lateral ligament is most commonly injured?
Anterior talofibular ligament
Where does the anterior talofibular ligament span between?
Lateral malleolus and lateral aspect of talus
Where does the posterior talofibular ligament span between?
Lateral malleolus + posterior aspect of talus
Where does the calaneofibular ligament span between?
Lateral malleolus + calcaneus
Where do the medial ligaments span between?
Medial malleolus + talus/ calcaneus/ navicular bones
What do the bones of the foot do?
Provide mechanical support for the soft tissues
How many tarsal bones are there?
7
Which bones form the hind foot region of he foot?
Calcaneus and talus
Which bones form the Midfoot?
Navicular
Cuboid
Cuneiforms
Which bones form the forefoot?
Metatarsals and phalanges
How many rows are the tarsal bones organised into?
3 (proximal, intermediate, distal).
What is the main function of the talus?
To transmit forces from the tibia to the calcaneus
Which bone forms the heel?
Calcaneus
Where is the calcaneus?
Inferior to the talus
Where is the navicular bone?
In between the talus and the cuneiforms.
Where is the cuboid bone?
Further lateral bone in the distal group of bones
Which bones form the transverse arch of the foot?
3 cuneiform bones
How do fractures of the talar neck normal occur?
High energy injuries where the foot is forcibly dorsiflexed
How do talar body fractures usually happen?
Jumping from height
How is the calcaneus often fractured?
Axial loading such as falling from height
What are the 3 main ways that metatarsals can be fractured?
Direct blow
Stress fracture
Excessive inversion of the foot causing an avulsion fracture
Name the 3 arches in the foot.
Transverse arch
Medial longitudinal arch
Lateral longitudinal arch
Which bones form the medial arch of the foot?
Calcaneus, talus, navicular cuneiforms and first 3 metatarsals.
Which muscles support the medial arch of the foot?
Tibialis anterior and posterior
Fibularis longus
FDL
Flexor hallucis
Intrinsic foot muscles
Which ligaments support the medial arch of the foot?
Plantar ligaments
Medial ligament of the ankle joint
Which arch lies on the ground in the standing position?
Lateral arch
Which bones form the lateral arch of the foot?
Calcaneus, cuboid and 45h/5th metatarsals
Which muscles support the lateral arch of the foot?
Fibularis longus
FDL
Intrinsic foot muscles
Which ligaments support the lateral arch of the foot?
Plantar ligaments.
Which bones form the transverse arch of the foot?
Metatarsal bones
Cuboid
Cuneiforms
Which muscles support the transverse arch of the foot?
Fibularis longus
Tibialios posterior
Which ligaments support the transverse arch of the foot?
Plantar ligaments
Deep transverse metatarsal ligaments
Failure of which ligament leads to flat foot deformity?
Calcaneonavicular ligament (spring ligament)
Which arch of the foot is supported by the calcaneonavicular ligament?
The medial longitudinal arch
Where do extrinsic muscles of the foot arise from?
Leg compartments
What are extrinsic muscles of the foot responsible for?
Eversion
Inversion
Plantarflexion
Dorsiflexion
Where are intrinsic muscles of the foot located?
Within the foot
What are the intrinsic muscles of the foot responsible for?
Fine motor actions (e.g. movement of individual digits)
How many intrinsic muscles are in the dorsum of the foot?
2
What are the muscles ib the dorsum of the foot?
Extensor digitorum brevis
Extensor hallucis brevis
What are the functions of the extensor digitorum brevis and extensor hallucis brevis?
Toe + great toe extension
What is the innervation of the muscles in the dorsum of the foot?
Deep fibular nerve
How many intrinsic muscles are there in the sole of the foot?
10
Muscles in the sole of the foot are innervated by branches of which nerve?
Tibial
What are the collective functions of muscles in the sole of the foot?
Stabilise arches of foot and control movements of digits
Where does the neuromuscular plane in the foot lie?
Between the first and second layers.
Which layer do the long flexor tendons of the foot lie in?
Second layer
Which layer do the tendons of the tibialis posterior and peroneus longus lie in?
Fourth layer.
What is the function of tibialis posterior?
Inversion + plantar flexion of the foot
Contributes to stabilising medial arch of the foot
What is the innervation of tibialis posterior?
Tibial nerve
Where does tibialis posterior insert?
Plantar surfaces of medial tarsal bones.
What is the function of peroneus longus?
Eversion and plantarflesion of the foot.
Supports lateral and transverse foot arches.
What is the innervation of peroneus longus?
Superficial peroneal nerve
What is the insertion point of peroneus longus?
Medial cuneiform and base of 1st metatarsal