Flashcards in Lecture: Lower Limb 3: The Ankle Joint and Foot Deck (14):
Why is dorsiflexion the most stable position of the ankle joint?
Trochlea of talus is wider anteriorly than posteriorly
during dorsiflexion, the anterior part of the trochlea moves between malleoli, spreading tibia/fibula
this increases their grip on the talus
what lateral ligaments contribute to the stability of the ankle joint?
Anterior talofibular ligament
posterior talofibular ligament
what medial ligaments contribute to the stability of the ankle joint?
Deltoid ligament is attached to medial malleolus and fans out to attach to talus, navicular and calcaneus
movements possible at the ankle joint?
Describe the dorsiflexors of the leg
Anterior compartment of the leg
Supplied by deep fibular nerve
supplied by anterior tibial artery
Describe the plantarflexors of the leg
Posterior compartment of the leg
supplied by the tibial nerve
supplied by the posterior tibia artery
Comment on ankle sprains
Mostly inversion injuries
ligaments relatively avascular so heal slow
predispose to dislocation
if ligament detaches from bone, grows back weaker
what is the most common fracture to occur?
breaking off the head of the lateral malleolus
i.e. the head of the fibula as it is much weaker
What are the joints involved in the foot?
Transverse tarsal joint, which is made up of:
- talonavicular joint
- calcaneocuboid joint
What are the arches of the foot and what is their function?
Medial Longitudinal (MLA)
Lateral Longitudinal (LLA)
help distribute weight
increase flexibility of the foot
act as springboards for propulsion during movemet
Describe the MLA
comprised of calcaneus, talus, navicular, 3 cuneiforms and 3 medial metatarsals
MLA is higher and more important than LLA
Describe the LLA
Calcaneus, cuboid and lateral 2 metatarsals
smaller as on outside of the foot
describe the TA
Comprised of cuboid, 3 cuneiforms and bases of the 5 metatarsals