Ankle Flashcards
what motion occurs around the vertical axis?
abduction/adduction
What motion occurs around the coronal axis?
Dorsiflexion/plantarflexion
What motion occurs around the longitudinal axis?
inversion/eversion
How do you define calcaneovalgus?
Medial angle is increased (>180)
How do you define calcaneovarus?
Medial angle is decreased(<180)
What is the “ankle” joint?
Articulation btwn tibia/fibula and talus, commonly known as talocrural joint.
What type of joint is the talocrural joint? How many DOF?
synovial hinge joint with 1 DOF
What part of the talus does the tibia/fibula articulate with?
The body of the talus
Which leg bone bears the most Body weight?
Tibia (~90%)
What type of joint is the proximal tibiofibular joint?
Plane synovial
What type of joint is the distal tibiofibular joint?
Syndesmosis
What do you need for a stable ankle?
Strong stiff connection between the tibia and fibula
What are the three facets of the talus?
Trochlea (top, largest, wedge shaped)
Medial (smaller that articulates with tibia)
Lateral (Fibular or peroneal facet, larger)
What causes the axis of the ankle joint to be tilted?
The position of the lateral malleolus further down and posterior from the medial malleolus
What happens to the mortise joint when the ankle is dodrsiflexed?
The mortise joint has to slightly widen to accommodate for the wider anterior anterior trochlea.
What is considered the loose packed position of ankle?
Plantar flexion
What is Talar tilt?
inversion/eversion
What is Talar rotation?
abduction/adduction
How do you define what the talus is doing?
Define the motion in relation to the head of the talus.
What does the fibula do to accommodate the larger end of the “truncated cone” it articulates with?
Fibula will rise superiorly and anteriorly to accommodate the increased ROM that the wider end of the truncated cone causes. There is also movement at the proximal tibiofibular joint
In weight bearing as tibia moves over foot in dorsiflexion, where does the leg end up in relation to the foot?
Leg ends up more medial to the foot
How many joint capsules does the subtalar joint contain?
2
How many articulations does the subtalar joint have?
3
Where are the interosseous talocalcaneal ligament and the cervical ligament located?
In the tarsal canal
What is the average angle of the axis of inclination in the subtalar joint?
~42 degrees, almost impossible to measure in a living human
What happens during supination at subtalar joint in non-weight bearing?
Calcaneal inversion
Calcaneal aDduction
Calcaneal plantar flexion
OBLIGATORY MOTIONS!!!!!
What happens during pronation at subtalar joint in non-weight bearing?
Calcaneal eversion
Calcaneal aBduction
Calcaneal dorsi flexion
OBLIGATORY MOTIONS!!!!!
What happens during supination at subtalar joint in weight bearing?
Calcaneal inversion Talar aBduction Talar dorsiflexion OBLIGATORY MOTIONS!!!!! *tibiofibular lateral rotation
What happens during pronation at subtalar joint in weight bearing?
Calcaneal eversion Talar aDduction Talar PF OBLIGATORY MOTIONS!!!!! *tibiofibular medial rotation
If head of talus aDduction, what happens to the mortise?
Will rotate medially
If head of talus aBducts, what happens to the mortise?
Will rotate laterally
How are subtalar motions identified?
depends on WB (calcaneal motion only) vs NWB (calcaneal and talar motions)
If calcaneous goes into valgus (aBduction), the subtalar joint will be doing what motion?
Pronation (arch flattens)
increase tension in plantar aponeurosis (tie-rod)
If calcaneous goes into varus (aDduction), the subtalar joint will be doing what motion?
subtalar supination (arch rises) release tension in the plantar aponeurosis (tie-rod)
What articulations does the transverse tarsal joint consist of?
Talonavicular and calcaneocuboid
What is the closed packed position of the sub talar joint?
supination
How are the subtalar and the transverse tarsal joint related?
complex interdependence
What is the function of the transverse tarsal joint?
Add to subtalar ROM
“compensate” for hindfoot position
What type of joints are the tarsometatarsal joint?
plane synovial joints
What happens in the supination twist?
inversion
1,2 metatarsals DF
4,5 metatarsal PF
Last ditch effort to keep forefoot on ground
What happens in a pronation twist?
Eversion
1,2 metatarsal PF
4,5 metatarsal DF
Last ditch effort to keep forefoot on ground
What axis do you rotate around when you stand on your toes?
Around metatarsal break (angled)
Muscles that insert anterior to the talocrural joint axis cause _______.
dorsiflexion
Ext hallucis longus, tib anterior, ext digitorum longus, peroneus tertius
Muscles that insert posterior to the talocrural joint axis cause _______.
plantarflexion
tib posterior, flex digitorum longus, flexor hallucis longus, triceps surae, peroneus brevis, peroneus longus
Muscles that insert medial to the subtalar joint axis cause _______.
supination
extensor hallucis longus, tibialis anterior, tibialis posterior, flexor digitorum longus, flexor hallucis longus, tricpes surae
Muscles that insert lateral to the subtalar joint axis cause _______.
extensor digitorum longus, peroneus tertius, peroneus brevis, peroneus longus
Which intrinsic muscle extends the MTP joints?
extensor digitorum brevis
Which intrinsic muscle abducts and flexes MTP of hallux?
abductor hallucis
Which intrinsic muscle flexes PIP of four lesser toes?
flexor digitorum brevis
Which intrinsic muscle abducts and flexes small toe?
adbuctor digiti minimi
Which intrinsic muscle adjusts oblique pull of flexor digitorum longus into line with long axes of digits?
quadratus plantae
Which intrinsic muscle flexes MTPs and extends IPs of 4 lesser toeas?
lumbricals
Which intrinsic muscle flexes MTP of hallux?
flexor hallucis brevis
Which intrinsic muscle has oblique head (adducts and flexes MTP of hallux) and transverse head (adducts MT heads transversely)?
adductor hallucis
Which intrinsic muscle flexes MTP of small toe?
flexor digiti minimi
Which intrinsic muscle adducts MTP of toes 3-5, flexes MTPs, and extends IPs of 4 lesser toes?
plantar interossei
Which intrinsic muscle abducts MTPs of 2nd toe, abducts MTPs, 3rd and 4th toes, extends IPs of 4 lesser toes?
dorsal interossei
Tension in the __________ caused by MTP joint extension can draw the hindfoot and forefoot together to raise the longitudinal arch.
plantar aponeurosis (this happens during supination of WB foot)
100% BW goes through the TALUS with 50% passing posteriorly to the ______ and 50% passing anteriorly to the ________.
Post: calcaneus
Ant. to forefoot: talonaviular and calcaneocuboid joints
