Foot And Ankle Flashcards
(66 cards)
What makes up the hindfoot (rear foot) region of the foot?
Hindfoot (rear foot)
-Calaneus
- Talus
What makes up the midfoot region of the foot?
Midfoot
- Navicular
- Cuboid
- Cuneiforms
What makes up the forefoot region of the foot?
Forefoot
- 5 metatarsals
- Phalanges
What are the motions of the ankle/foot?
- Dorsiflexion and Plantarflexion
- Inversion: plantar surface moves toward midline
- Eversion: plantar surface moves away from midline
- Abuction: distal aspect of segment moves away from midline
- Adduction: distal aspect of segment moves toward midline
What are the composite motions for supination (NWBing)
Supination- coupled plantarflexion, inversion, and adduction
What are the composite motions for Pronation (NWBing)
Pronation: coupled dorsiflexion, eversion, and abduction
What is the axis of the talocrural joint in neutral?
In neutral:
Axis passes through lateral malleolus, body of talus and medial malleolus
Lateral malleolus and fibular facet of talus are more distal and posterior than tibial counterparts
-> creates oblique axis
Lateral malleolus sits more posteriorly due to normal tibial torsion
How does the talocrural joint functionally move in open chain DF and PF?
Open chain DF
- Foot moves upward and slightly lateral to lower leg
- Foot appears to turn longitudinally away from midline
Open chain PF
- Foot moves down and slightly medial to lower leg
- Appears to turn longitudinally toward midline
** How does the talocrural joint move in WBing DF and PF
WBing DF
- Tibia and fibula move toward and medial to foot
- Lower leg rotates medically in transverse plane
WBing PF
- Tibia and fibula move away from and lateral to foot
- Lower leg rotates laterally in transverse plane
What does the Deltoid ligament do?
Resists eversion at talocrural, subtalar, and talonavicular jts
What does the anterior talofibular ligament do?
(Lateral ligament) Restricts combined motion of plantarflexion with inversion or adduction
*****What does the calcaneofibular ligament do
Restricts inversion or varus stress of the talocrural and subtalar joints (its like a lateral collateral ligament)
*****What does the posterior talofibular ligament do
Provides stability to the talus within the joint and restrict abduction during dorsiflexion
**What is tibial torsion
Accounts for “normal” toe-out position of foot in standing
-> similar to that of femur, but typically in opposite direction
Lateral tibial torsion increases from birth until 10yrs
-> ankle jt axis becomes positioned more laterally as torsion increases
Normative values are variable
-> ~20 degrees of lateral torsion (adults)
***Characteristics of the proximal tibiofibular jt
- plane, synovial jt
- Variability of jt surfaces
-> most common: convex tibial facet and concave fibular facet - Capsule reinforced by anterior and posterior tibiofibular ligaments
Characteristics of the distal tibiofibular jt
- syndesmosis b/w concave facet of tibia and convex facet of fibula
- tibia and fibula separated by fibroadispose tissue
- anterior and posterior tibiofibular ligaments and interosseous membrane provide support
What does the Calceneofibular ligament limit?
Limits excessive inversion
What does the tibiocalcaneal fibers of the deltoid ligament limit?
Limits excessive eversion
What does the Interosseous (talocalcaneal) ligament do?
Binds talus with calcaneus; limits extremes of all motions (esp. inversion)
What does the Cervical ligament do?
Binds talus with calcaneus; limits extremes of all motions (esp. inversion)
***What is the function of the Subtalar joint?
3 articulations with alternating convex-concave facets
- Limit joint mobility
- Creates triplanar motion around oblique joint axis
- Motion is complex twisting or screw like motion
-> Pronation/supination
Posterior calcaneal facet is convex
Middle and anterior facets of the calcaneus are concave
What are the Couple motions of the Subtalar in NWBing supination and pronation
Supination
- Calcaneal inversion (calcaneal varus)
- Calcaneal adduction
- Calcaneal plantarflexion
Pronation
- Calcaneal eversion (calcaneal valgus)
- Calcaneal abduction
- Calcaneal dorsiflexion
What are the Couple motions of the Subtalar in WBing supination and pronation
Supination
- Calcaneal inversion (or varus)
- Talar abduction (or lateral rotation)
- Talar dorsiflexion
- Tibiofibular lateral rotation
-> Causes Talar abduction
-> carries mortise laterally, producing ER of lower leg
DF and abduction of talus is observed in elevation of medial longitudinal arch and convexity on the dorsal lateral midfoot
Pronation
- Calcaneal eversion (or valgus)
- Talar adduction (or medial rotation)
- Talar plantarflexion
- Tibiofibular medial rotation
-> Causes Talar adduction
-> Body of talus rotates medially, brings lower leg into IR
PF and adduction of talus is observed in the lowering of medial longitudinal arch and convexity of the plantar medial midfoot
What makes up the Transverse Tarsal joint
Compound jt btwn rearfoot and midfoot
- Talonavicular jt
- Calcaneocuboid jt
- Involved in pronation and supination
- Anatomically and functionally related to subtalar jt
- Plays major role in compensatory motions to adjust to variations in ground surface