The Foot Flashcards
What are the functions of the plantar aponeurosis?
- Grip and weight bearing.
- Thickens as 5 longitudinal bands that continue with the fibrous flexor sheaths of the toes.
- Sends septae to metatarsals to create compartments and potential spaces
What are plantar muscles supplied by?
Lateral or Medial plantar nerves
What muscles are found in layer 1 of plantar muscles and what is their nerve supply?
Flexor digitorum Brevis - Medial plantar.
Abductor hallucis - Medial plantar.
Abductor digiti minimi - lateral plantar
What muscles are in layer 2 of plantar muscles and what is their nerve supply
Lumbricals 1-4 (lumbrical one is supplied by medial, 2-4 are supplied by lateral). Quadratus plantae (lateral plantar nerve)
What muscles are in layer 3 of plantar muscles and what are their nerve supplies?
Adductor hallucis (lateral planter).
Flexor hallicus brevis (medial plantar N).
Flexor digiti minimi brevis (lateral plantar N)
What muscles are in the 4th layer of plantar muscles and what is their nerve supply
3 Plantar interossei - adduction (lateral plantar nerve).
4 Dorsal interossei -abduction (lateral plantar nerve)
Describe features of plantar arteries
The posterior tibial artery passes behind the medial malleolus and becomes the medial and lateral plantar arteries. Lateral contributes more to deep plantar arch
What happens with a fracture of the neck of talus?
It will interrupt the blood supply to the head of talus causing avascular necrosis.
Describe features of the plantar nerves
The tibial nerve bases behind the medial malleolus into the sole deep to the flexor retinaculum and then divides into the medial and lateral plantar nerves.
What are the points of contacts of the foot with the flooe?
calcaneus and heads of all metatarsals.
What are the functions of the arches in the feet
Weight bare and distribute forces, absorb shock and resilience.
What is the medial longitudinal arch made up out of?
Calcaneus, talus, navicular, all 3 cuniforms and medial 3 metatarsals
What is the lateral longitudinal arch made up out of?
Calcaneus, cuboid and 4th and 5th lateral metatarsals.
What is the transverse arch made up out of?
Cuboid and all 3 cuniforms
What are some passive supporters of the arches
1) shapes of the bones with the head of talus being the ‘keystone’ of the medial arch.
2) Strong ligaments
What are the strong ligaments that support the arches
Calcaneonavicular plantar ligament (supports the keystone and is therefore the most important). Long plantar ligament. Plantar aponeurosis. Deltoid ligament (extends from tibia). Calcaneocuboid (short plantar) ligament.
What are some active supporters?
Muscles when they are contracted
What are the passive and active supporters of the medial longitudinal arch?
Passive - Deltoid ligament, plantar aponeurosis and spring ligament.
Active - Flexor hallucis longus, tibialis posterior and tibialis anterior.
What are the passive and active supporters of the lateral arch
Passive - Short plantar ligament, long palmar ligament, lateral ligament and plantar aponeurosis.
Active - Fibularis longus tendon and flexor digitorum longus
What are the muscles on the dorsum of the foot? what are they supplied by?
Extensor digitorum brevis and extensor hallucis brevis which are supplied by the deep fibular nerve
What is the function of the extensor and flexor retinaculum ?
Keep the extensor and flexor tendons + neurovascular bundles held down/ in place.
What is the tarsal tunnel?
The depression inferior to the medial malleolus formed by talus, calcaneus and flexor retinaculum.
What passes through the tarsal tunnel
Tendons for flexor hallucis longus, flexor digitorum longus and tibialis posterior and neurovascular structures.
What is the lisfranc joint?
Where the tarsals meet the metatarsals
