Ankle 4 Flashcards
- Subtalar (Talocalcaneal) Joint
- Articulations
- Talus (concave)
- Calcaneus (convex)
Subtalar (Talocalcaneal) Joint
- In Open chain kinematic
- Inversion
calcaneus roll medially and slide laterally on a fixed talus
Subtalar (Talocalcaneal) Joint
- In Open chain kinematic
- Eversion
calcaneus roll laterally and slide medially on a fixed talus
Subtalar Ratio
2:1 Inversion:Eversion
- Medial Talocalcaneal Ligament
- Connects the
medial tubercle of the talus with the sustentaculm tali
Medial Talocalcaneal Ligament limits
anterior translation of the talus
eversion
- Lateral Talocalcaneal Ligament
- Connects the
lateral process of the talus to the lateral surface of the calcaneus
Interosseous (Talocalcaneal) Ligament
- Has a
posterior and anterior band (cervical ligament)
Interosseous (Talocalcaneal) Ligament stabilize the
subtalar joint
- Subtalar Joint - Open Chain (Non WB)
- the talus is stable, and the calcaneus and foot move
around the talus
Subtalar Joint - Open Chain (Non WB)
Supination
Calcaneus
- PF, Inversion, Adduction
Subtalar Joint - Open Chain (Non WB)
Pronation
- CalcaneusDF, Eversion, Abduction
Subtalar Joint - Close Chain (WB)
Supination
- Calcaneus
Inversion - Talus
DF and ABD - Tibia
slight ER
Subtalar Joint - Close Chain (WB)
Pronation
- CalcaneusEversion,
- TalusPF, Adduction
- TibiaSlight IR
- Transverse Tarsal Joint
- Chopart or Midtarsal Joint formed by
- Talonavicular joint
- Calcaneocuboid joint
- Does pronation and supination
Transverse Tarsal Joint linked mechanically with
STJ
Transverse Tarsal Joint is the transitional link between the
hindfoot and forefoot
Transverse tarsal joint Compensates the forefoot for
hindfoot position
(keeps forefoot flat on ground as hindfoot accommodate to terrain)
Transverse Tarsal Joint important in
hollowing feet
Talonavicular Ligament
Stabilizes ______
Limits _______
talonavicular joint
PF and inversion of navicular
Bifurcate Ligament:
Calcaneonavicular ligament is ______ portion
Calcaneocuboid Ligament is _______ portion
Medial
Lateral
Bifurcate Ligament
Both function to stabilize the _________
Taut in_______
midtarsal joint
supination
- Spring Ligament
- Connects navicular to
sustenaculum tali
Spring ligament Functions as a ligamentous sling for the
- head of the talus and becomes taut during pronation
Spring Ligament limits
navicular PF
Spring Ligament supports
medial longitudinal arch
- Long and short plantar ligaments
- Long —> forms tunnel for
FL tendon
Long and short plantar ligaments
Both limits depression of
longitudinal arch
With the calcaneus held fixed, pronation and supination occur primarily at the
midfoot
When the calcaneus is free, pronation and supination occur as a summation across both the
rearfoot and midfoot
Plantar Fascia/Aponeurosis
Apex towards the
heel
Plantar Fascia/Aponeurosis
Base toward the
toes
Plantar Fascia/Aponeurosis
Functions
- Maintain longitudinal arch
- Provide origins of superficial plantar muscles
- Protect plantar vessels and nerves from compression
Windlass Effect
Propulsion during toe off in gait
Plantar fascia shortens
Windlass Effect
Great toe DF/Ext
winds (shortens) the plantar fascia →
- shortens the distance b/w calcaneus and base of metatarsal →
creates a mechanical advantage for propulsion
Windlass Effect
If this is limited
can’t wind (shorten) plantar fascia and will have less propulsion force in swing phase
Tarsometatarsal Joints (LisFranc)
Type of Joint _______
Contribute to ______
synovial plane joint
hollowing and flattening of the foot
Tarsometatarsal Joints (LisFranc)
2nd TMT joint is
stronger and its motion more restricted
Tarsometatarsal Joints (LisFranc)
Primary Function in WB
- Augment function of transverse tarsal joint
- Regulate position of forefoot in relation to WB surface
Tarsometatarsal Joints (LisFranc)
Reinforced by numerous
dorsal, plantar, and interosseous ligaments
