Ankle and Foot Flashcards
Pronation in open chain
Calcaneus DF
Calcaneus AB
Calcaneus EV
Supination in open chain
Calcaneus PF
Calcaneus AD
Calcaneus IN
Pronation in closed chain
Calcaneus EV
Talus AD
Talus PF
Tibial medial rotation
Supination in closed chain
Calcaneus IN
Talus AB
Talus DF
Tibial lateral rotation
Talocrural joint formed by the
Concavity of the distal end tibia and both malleoli, and the convex trochlea of the talus
MCL in the ankle
Anterior tibiotalar Posterior tibiotalar Tibionavicular Tibiocalcaneal Resists eversion sprains
LCL in the ankle
Anterior talofibular (most common ligament sprain)
Posterior talofibular
Calcaneofibular
Resists inversion sprains (most common)
Main component of pronation in talocrural joint is
DF
Main component of supination in talocrural joint is
PF
DF at the talocrural joint
Superior surface of the talus rolls anterior and slides posterior in open chain
What ligament become taut in DF of the talocrural joint?
calcaneofibular ligament
PF at the talocrural joint
superior surface of the talus rolls posterior and slides anterior in open chain
What ligament becomes taut in PF of the talocrural joint?
Tibionavicular ligament
What ligament is stretched during PF of the talocrural joint?
Anterior tibiofibular ligament
Main components of pronation in the subtalar joint in open chain are
Eversion and abduction
Main components of supination in the subtalar joint in open chain are
Inversion and adduction
What happens if you cannot maintain all 5 rays in contact with the ground?
You lose feed forward mechanisms to your CNS which is going to decrease your ability for proprioceptive and neuromuscular control
Transverse tarsal joint or mid-tarsal joint consists of
Calcaneocubioid joint (which provides more stability and less mobility) and the talonavicular joint (which provides more mobility but is still extremely stable)
The mid-tarsal joint works together with the STJ to
control most of the pronation and supination
Pronation and supination occurs as the navicular…
spins as the calcaneus is held firmly in place
Navicular cannot move…
independent of the talus, strong ligamentous connections there, need complete dislocation and tear of every major stabilizer
The function of the TTJ is complicated by
- two separate axises of rotation
- movement different during WB and NWB
- stabilizing function of the TTJ at the mid foot is influenced by the position of the subtler joint (STJ coach, TTJ players)
2 axes of the TTJ
longitudinal - Primary motion EV/IN
oblique - strong vertical and med-lat pitch
Main components of pronation in the TTJ in open chain are
DF/AB/EV
Main components of supination in the TTJ in open chain are
PF/AD/IN
What is your primary supinator?
Tibialis posterior
Will eccentrically control pronation
If someone is overly pronating they might develop…
Tibialis posterior tendinopathy - because they are putting a lot of tensile forces through their TP
What initiates the spin of the navicular?
The tibias posterior. This will tighten the spring ligament around the convex head of talus
What is your primary pronator?
Fibularis longus
Contributes to lowering of the medial side (1st ray) of the foot and raising of the lateral side
What is the function of the plantar fascia?
Give passive stability and primary support of the medial longitudinal arch
What stretches the central fascia?
Active toe extension (especially of the big toe), which should push the medial longitudinal arch higher. If you’re excessively pronated and that fascia is stretched out, it doesn’t have the ability to develop any tension to give it bowstringing so that you can get more of an arch
Combined action STJ and TTJ during stance phase gait
Just after heel strike the STJ will pronate unlocking the MTJ so the foot is flexible and can adapt to the ground. Late stance the STJ will supinate locking the MTJ creating a rigid stable base for push off to propel the LE for swing
Windlass mechanism
The windlass action causes the longitudinal arches of the foot to rise when the toes are extended as well as stiffening the fibrous tissues of the ball of the foot during push off.
The windlass action is most evident in the medial arch with extension of the hallux.
One risk factor is a pronated foot, another is limited dorsiflexion (don’t get that stretch through the plantar fascia so you’re walking through a very hypo mobile foot, lots of traction)
Pronation occurs during
Supination occurs during
Initial contact = increased foot mobility
Terminal stance = increased foot stability
Who is more likely to have overuse injuries? Stress fractures?
People with low arches are more likely to have overuse injuries (because foot is not very stable). People with high arches more likely to have stress fractures (because they can’t disperse force).
During walking, the 1st ray…
Dorsiflexes and everts during the loading phase, and then plantar flexes and inverts during the propulsion phase (puts tension through the plantar fascia which acts as a bowstring and lifts arch to increase stability)
Altered mobility of the 1st ray can result in
Excess rear foot pronation and supination and the development of bunions