Lecture 11 - Foot

Question 1

Dorsum of Foot

Answer 1

• Anterior tibial artery via dorsalis pedis artery
• Arcuate artery: •Termination of arcuate artery •Gives off dorsal metatarsals to dorsal digitals
• Deep plantar artery

Nerve supply:
•Superficial peroneal nerve: •Gives rise to medial and intermediate dorsal cutaneous nerves •Cutaneous
•Deep peroneal nerve: •Lateral branch is motor to intrinsic muscles on dorsum: •Extensor hallucisbrevis •Extensor digitorumbrevis •Medial branch is cutaneous
•Sural nerve: •Gives off lateral dorsal cutaneous nerve

Question 2

Peroneal Retinacular Complex

Answer 2

Superior peroneal/Inferior peroneal

•Tendons of both the peroneus longus and brevis pass through both of these retinacula.

Question 3

Extensor retinaculum

Answer 3

“Y”-shaped complex with stem of “Y” on lateral side of ankle.
For tendons of extensor digitorum longus, extensor hallucis longus, and tibialis anterior

Question 4

Flexor retinaculum

Answer 4

For tendons of tibialis posterior, flexor digitorum longus, and flexor hallucis longus

Question 5

Dorsal Foot Muscles

Answer 5

Extensor digitorum brevis

Extensor hallucis brevis:
•Sometimes considered part of extensor digitorum brevis

Dorsal interossei:
•Abductors
•Second toe is reference

Question 6

Sole of Foot

Answer 6

Blood supply:
•Posterior tibial artery
•Medial and lateral plantar arteries
•Perforating arteries

Nerve supply: 
Cutaneous: 
•Tibial nerve: 
•Medial calcaneal 
•Medial plantar 
•Lateral plantar 
•Saphenous nerve 
•Sural nerve 
Motor: 
•Tibial nerve via lateral and medial plantar nerves

Question 7

Muscle Layers of Sole of Foot

Answer 7

Superficial layer, 1-4th layers

Question 8

Superficial layers

Answer 8

• Skin

* Plantar aponeurosis

Question 9

First muscle layer

Answer 9

•Abductor hallucis 
•Flexor digitorum brevis 
•Abductor digiti minimi 
Tendons in first layer: 
•Flexor digitorum longus tendon 
•Flexor hallucis longus tendon

Question 10

Second Muscle Layer

Answer 10

• Quadratus plantae

* Lumbricals

Question 11

Third Muscle Layer

Answer 11

• Flexor hallucis longus tendon:
• Passes between sesamoid bones in tendons of flexor hallucis brevis
• Adductor hallucis
• Flexor digiti minimi brevis

Question 12

Fourth Muscle Layer

Answer 12

Peroneus longus tendon

Tibialis posterior tendon

Interossei:
•Three plantar (adductors)
•Four dorsal (abductors)

Question 13

Abductor Hallicus

Answer 13

First Layer
Origin: calcaneal tuberosity
Insertion: medial sesamoid and base of proximal phalanx of great toe
Action: Abducts great toe at MP joint; helps flex MP join
Innervation: Medial Planar (S1-2)

Question 14

Flexor Digitorum Brevis

Answer 14

First Layer
Origin: calcaneal tuberosity
Insertion: sides of middle phalanges of digits 2-5
Action: flexes PIP joints of digits 2-5
Innervation: medial plantar (L5; S1-2)

Question 15

Abductor Digiti Minimi

Answer 15

First Layer
Origin: Calcaneal Tuberosity
Insertion: Proximal Phalanx of little toe
Action: Abducts the little toe and MP joint
Innervation: Lateral Planar (S2-3)

Question 16

Quadratus Plantae

Answer 16

Second Layer
Origin: medial head from medial aspect of plantar surface of calcaneus; lateral head from lateral aspect of plantar aspect of calcaneus
Insertion: lateral edge of the tendon of the flexor digitorum brevis
Action: May help to flex DIP joints of digits 2-5
Innervation: Lateral plantar (s2-3)

Question 17

Lumbricals

Answer 17

Second Layer
Origin: First Lumbrical from long tendon of second digit; three lateral lumbricals form intervals between the adjacent long flexor tendons
Insertion: medial side to join the extensor tendons on the proximal phalanges of digits 2-5
Action: flexes the MP joints and extends the PIP and DIP joints of digits 2-5
Innervation: Lumbricals 2-4 lateral plantar nerve (s2-3); Lumbrical 1: Medial plantar nerve (S2-3)

Question 18

Flexor Hallicus Brevis

Answer 18

Third Layer
Origin: plantar surfaces of cuboid and lateral cuneiforms
Insertion: both sides of base and proximal phalanx of first digit
Action: flexes proximal phalanx of first digit
Innervation: medial plantar (s2-3)

Question 19

Adductor Hallicus

Answer 19

Third Layer
Origin: oblique head from peroneus longus sheath and bases of metatarsals 2-4; transverse head from plantar metatarsophalangeal ligaments of digits 2-4
Insertion: base of proximal phalanx of the great toe with the flexor hallicus brevis
Action: adducts the great toe at the MP joint
Innervation: lateral plantar (s2-3)

Question 20

Flexor Digiti Minimi Brevis

Answer 20

Third Layer
Origin: sheath of peroneus longus and base of metatarsal 5
Insertion: base of proximal phalanx of little toe
Action: flexes the PIP joint of the little toe
Innervation: lateral plantar (s2-3)

Question 21

Dorsal Interossei

Answer 21

Fourth Layer
Origin: adjacent sides of shafts of metatarsals 1-5
Insertion: medial side of proxiam l phalanx of digit 2; lateral sides of digits 2-4
Action: abducts digits 2-4; flex metatarsal-phalangeal joints
Innervation: lateral plantar nerve (S2-3)

Question 22

Plantar Interossei

Answer 22

Foruth Layer
Origin: each head arises form the medial side of the base of each metatarsus 3-5 and from the sheath of the peroneus longus
Insertion: medial side of base of proximal phalanx of the same digit
Action: adducts digits 3-5 at the MP joints toward the axis of the second toe; flexes the MP joints and extends the PIP and DIP joints of digits 3-5
Innervation: lateral plantar nerve (S2-3)