Foot and Ankle Flashcards
What is fascia?
Thick connective tissue
What is the fascia on the sole of the foot?
Plantar fascia
What is the central thickest part of the plantar fascia that runs longitudinally down the foot called?
Plantar aponeurosis
Origin and function of plantar aponeurosis
O: Posterior calcaneus
Function: support the longitudinal foot arches
What is plantar fascitis?
Inflammation of the plantar aponeurosis at the proximal attachment to the calcaneus
What causes plantar fascitis and when is the pain severe?
Causes: overweight, bad shoes, high impact exercise, running
Pain is more severe after sitting and when getting out of bed
What can plantar fascitis lead to?
Heel spur syndrome - bony spur around medial tubercle of calcaneus
What are the dorsum foot muscles?
Extensor hallucis brevis and Extensor digitorum brevis
Origin, insertion, action, innervation of extensor hallucis brevis
O: Superolateral calcaneus and interosseous talocalcaneal L.
I: Base of 1st proximal phalynx
Innvervation: Deep fibular nerve
Action: extend hallux (big toe) at metatarsophalangeal joint
Origin, insertion, action, innervation of extensor digitorum brevis
O: superolateral calcaneus and interosseous talcalcaneal L.
I: Extensor digitorum longus tendon
Action: Extend digits 2-4 (not pinky toe)
Innervation: Deep fibular nerve
What are the muscles in the first layer of the plantar aspect?
Abductor digiti minimi, flexor digitorum brevis, abductor hallucis
How many layers of muscles are there in the plantar aspect of the foot?
4
Origin, insertion, action, innervation of abductor digiti minimi
O: Calcaneal tuberosity
I: Base of 5th proximal phalanx
Action: ABduct and flex 5th digit
Innervation: Lateral plantar n.
Origin, insertion, action, innervation of flexor digitorum brevis
O: calcaneal tuberosity
I: 2-5 intermediate phalanges
Action: flex digits 2-5
Innervation: medial plantar n.
Origin, insertion, action, innervation of abductor hallucis
O: calcaneal tuberosity
I: 1st proximal phalanx
Action: ABduct and flex hallux
Innervation: Medial plantar n.
What are the muscles in layer 2 of the plantar foot?
Quadratus plantae and lumbricals
Origin, insertion, action, innervation of quadratus plantae
O: Plantar surface of calcaneus
I: Flexor digitorum longus Tendon
Innervation: Lateral plantar n.
Action: Help flex digits 2-5
Origin, insertion, action, innervation of lumbricals
O: Flexor digitorum longus tendon
I: Proximal phalanx of digits 2-5 and medial aspects of digital expansion
Innvervation: 1st lumbrical = medial plantar nerve
2-4th lumbricals = lateral plantar nerve
Action: Flex MP joint and extend PIP and DIP joints
What does MP stand for
Metatarsophalangeal joint
What does PIP stand for
Proximal interphalangeal joint
What does DIP stand for
Distal interphalangeal joint
What are the muscles in layer 3 of the plantar foot?
Flexor digiti minimi brevis, adductor hallucis, flexor hallucis brevis
Origin, insertion, action, innervation of flexor digiti minimi brevis
O: Base of 5th metatarsal
I: 5th proximal phalanx
Innervation: Superficial lateral plantar n.
Action: Flex proximal phalanx of 5th digit
Origin, insertion, action, innervation of adductor hallucis
O: Transverse head: MP joints Oblique head: Bases of 2-4 metatarsals I: Lateral base of 1st proximal phalanx Innervation: Deep lateral plantar n. Action: ADduct hallux
Origin, insertion, action, innervation of flexor hallucis brevis
O: plantar surface of cuboid and lateral cuneiform
I: 1st proximal phalanx - medial and lateral heads
Innervation: Medial plantar n.
Action: Protect 1st metatarsal head and FHL tendon when walking/standing, have sesamoid bones as well
What are the muscles in layer 4 of the plantar foot?
Plantar and Dorsal interossei
Origin, insertion, action, innervation of plantar interossei
O: medial bases of 3-5 metatarsals
I: Medial aspects of 3-5 proximal phalanges
Innervation: Lateral plantar nerve
Action: PAD - ADDduct digits 3-5
Origin, insertion, action, and innervation of dorsal interossei
O: Bases of 1st - 5th metatarsals
I: Lateral aspects of 2 - 4 proximal phalanges and medial aspect of 2nd proximal phalanx as well
Innervation: lateral plantar nerve
Action: DAB - ABduct digits 2-4
What is hallux valgus
Lateral deviation of the great toe
What is a tender and inflamed bursa
Bunion
What is an inflamed area of thick skin over proximal IP joint called?
Corn
List 4 toe deformities
Hammer toes, claw toes, mallet toes, trigger toe
How do hammer toes arise?
Proximal phalanx hyperextended, distal phalanx plantar flexed at PIP joint, distal phalanx extended
How do claw toes arise?
Proximal phalanx hyperextended at MP joint, flexion of distal and proximal IP joints
What usually causes toe deformities?
Shortened flexor muscles that override lumbrical function
How do mallet toes arise?
Only flexion at the distal IP joint
How does a trigger toe arise?
Only flexion at the IP joint of the big toe
How does the tibial nerve innervate the foot?
It splits into the medial plantar nerve and the lateral plantar nerve, the lateral plantar nerve has a deep and superficial branch
What 4 muscles does the medial plantar nerve innervate?
Abductor hallucis, flexor digitorum brevis, medial one lumbrical, flexor hallucis brevis
Lateral plantar nerve innervates the REST!!!!
Cutaneous innervation of the top of the foot?
Medial dorsal cutaneous (superficial fibular nerve)
Cutaneous innervation using the deep fibular nerve?
Lateral cuteanous nerve of the big toe and medial cutaneous nerve of the 2nd toe
What 4 ligaments make up the deltoid (medial) L?
Anterior and posterior tibiotalar, tibionavicular, tibiocalcaneal
What 3 ligaments make up the lateral L?
Anterior and posterior talofibular, calcaneofibular
What is the dorsum fascia of the foot continuous with?
Extensor retiniculum
