Ankle Flashcards
What bones from true ankle joint?
Talus
Fibula
Tibia
How is joint formed?
Two malleolus (lateral and medial) form depression mortise
Joint type and movement
Plantarflexion, dorsiflexion (hinge synovial)
How are tibia and fibula stabilised?
Tibiofibular joint - stabilises ankle joint
When is ankle joint most stable?
During dorsiflexion
Plantarflexion (narrower posterior of talus)
Two main ligaments
Medial - deltoid
Lateral (weaker)
Deltoid ligament
resists over eversion and plantarflexion
medial malleolus to talus, calcaneus, navicular
Ligaments that make up deltoid
anterior tibiotalar
tibionavicular
tibiocalcaneal
posterior tibiotalar
Lateral ligaments
Anterior talofibular
Posterior talofibular
Calcaneofibular
Subtalar joint
Talus and calcaneus
involved in inversion and eversion
Properties of ankle joint capsule
Must be slack anteriorly and posteriorly as dorsi and plantar flexion are allowed
Anterior tibiotalar, Tibionavicular and tibiocalcaneus function
Limits plantar flexion and eversion
Posterior tibiotalar function
Prevents over dorsiflexion
Clinical relevance anterior talofibular ligament
Commonly damaged during over inversion
Plantar flexion = unstable and if inverted could rupture
Which ligaments are stronger and what does this mean?
Medial ligaments are stronger than lateral
Medial ligaments prevent eversion
Lateral ligaments prevent inversion
If ankle twists, foot often rolls onto outside (lateral) of foot (inversion)