Exam 1 - Foot & Ankle Complex Flashcards
What are the 2 main functions of the foot/ankle complex?
- Stable base of support
- Shock absorption
Bones of the ankle
- distal tibia
- distal fibula
- talus
What 2 bones make a mortise?
Fibula and tibia, held together by interosseous membrane
- allow talus to pass through
What forms a malleoli?
Ends of tibia & fibula
- L. little hammer
Hindfoot
Talus and calcaneus
Mid-foot
3 cuneiforms, navicular, cuboid
Forefoot
Metatarsals & phalanges
Tarsals
7 bones
- Gr. tarsos, any flat surface
Metatarsals
Gr. Meta, after
Phalanges
- Gr. phalanx, line of battle
Joints
4 mains
- ankle
- subtalor
- tarsometatarsal
- metatarsalphalangeal
2 motion of the ankle
Plantarflexion (point) - 50 degrees
Dorsiflexion - 30 degrees
Talus
- wider anteriorly
- narrower posteriorly
- often fractured in dislocations of the ankle
- upward arterial supply
- prone to necrosis with severe injury
- avascular necrosid
“Snowboarder’s Fracture”
Subtalar Joint
“Below the ankle”
- between talus and calcaneus
- calcaneum = L. Heel
- inversion: 30 degrees
- eversion: 10 degrees
Subtalar Neutral
- in the middle
- “optimally aligned foot”
- best stress distribution
Tarsometatarsal Joint
3 cuneiforms and cuboid with metatarsals
- helps regulate positions of the foot
Metatarsopharangeal Joint
“MTP”
- 5 joints
- primarily flexion and extension
- hinge to allow heel to rise while toes stabilize
- gait
6 main movements
- plantarflexion
- dorsiflexion
- inversion
- eversion
- pronation
- supination
Pronation
Foot rolls inwards
- eversion
- dorsiflexion
P. E. D.
Supination
- Foot rolls outward
- inversion
- plantarflexion
S.I.P.
Ligaments
~60 Main ligaments 1. Interosseous membrane 2. Deltoid ligament 3. Anterior Talofibular Ligament 4. Plantar Calcaneonavicular Ligament