Flashcards in Lecture 9.2 Deck (30):
What is more stable dorsiflexion or plantarflexion?
What kind of joint is the talocrural joint?
Hinge joint; oriented in a similar way to the ball and socket joint
What is the function of the inferior transverse ligament?
The inferior transverse ligament prevents posterior movement of the malleolar mortise.
What are the components of the medial collateral ligament of the foot?
posterior and anterior tibiotalar
What is the function of the medial collateral ligament?
prevent too much eversion
Is the medial collateral ligament continuous or split?
continuous and blends with fibrous capsule of the joint
What shape are the collateral ligaments?
Why is the lateral collateral ligament so commonly sprained?
Because it is split into discrete parts
What are the parts of the lateral collateral ligament?
anterior and posterior talofibular
What muscles are involved in dorsiflexion?
Why is dorsiflexion better for stability?
The talus is wider anteriorly meaning contact with the malleoli is stronger
What are the main intertarsal joints?
TaloCalcaneoNavicular joint (TCN)
What kind of joint are the TCN and the subtalar joints?
modified ball and socket joints. with concave/convex facets on talus, calcaneus, and navicular
What is the sustentaculum tali?
The bit of the calcaneous that takes up the talus. It also provides the surface for interosseus ligament to attach to it.
What is the sinus tarsi?
The space between the calcaneus and the talus
What shape is the TCN joint mobility?
What motion does this joint allow?
oblique shaped allows inversion and eversion
What joint is the TCN a part of functionally (anterior and middle part)?
What type of joint is the calcaneocuboid joint?
plane synovial joint. With TCN it functionally forms the midtarsal joint.
What movements does the calcaneocuboid joint allow?
pronation and supination
What kind of overall motion is pronation of the foot?
Eversion + lateral rotation
What kind of overall motion is supination of the foot?
Inversion + medial rotation
What kind of rotation causes flat feet?
What structures help maintain the lateral longitudinal arch?
Long and short plantar ligaments
fibularis longus tendon
Which bones form the lateral longitudinal arch?
Metatarsals 4 & 5
Which bones form the medial longitudinal arch?
Talus (at the apex)
Medial 3 metatarsals
What bones form the transverse longitudinal arch?
Base of metatarsals
What structures help maintain the medial longitudinal arch?
Tibialis Anterior and Posterior (tendons are attached to first metatarsal and medial cuneiform)
What happens to the ligaments that maintain the arch with age?
They become lax and as a result may cause pronated feet
What structures help maintain the transverse longitudinal arch?
tibialis anterior 'sling'