3 - Zill - Sole of Foot

Question 1

What biomechanical machines does the foot act as?

Where is weight supported on the foot?

Answer 1

Lever/Springs

1. Base of big toe (1st metatarsal) + heads of metatarsals (2-5) = 6 points of contact w/ground
2. Calcaneus (heel)

Question 2

Abduction

v

Aduction

in toes

Answer 2

Axis through second toe:

Abduct = Spread

Adduct = Toward mid-line

Second toe will pretty much always Abduct (movement away from midline)

Question 3

Plantar Aponeurosis

How does it further divide?

What structure does it support?

Answer 3

Tough band of deep fascia on sole of foot, extends from calcaneus

Distally divives into connective tissue bands for all five toes

- - -

Supports lateral arch

Question 4

Fibrous Digital Sheaths

Answer 4

Found on Flexor (Plantar) side of toes

Act like retinacula for toes

Question 5

Layer 1 of Sole Muscles

Common Origin?

Answer 5

Flexor Digitorum Brevis (middle)

Abductor Hallucis (outer, big toe abduct)

Abductor Digiti Minimi (inner, little toe abduct)

The names will tell you what they do JC!

- - -

Common Origin: Calcaneus

Question 6

Why is there a split in Flexor Digitorum Brevis?

Answer 6

Allow passge of flexor digitorum longus to distal phalanges

Question 7

Muscles of Foot - Layer 2

Flexor Digitorum Longus

Answer 7

Flexor Digitorum Longus (.. that long DICK)

O: Tibia

I: Distal phalanges of toes (w/lumbricals)

Tendons pass in split of Flexor Digitorum Brevis

Question 8

Lumbricals of Foot

Answer 8

Attach to tendons of Flexor Digitorum Longus

Actions:

Flex middle, Extend tip

Fine Movements!

Question 9

What muscle counters Flexor Digitorum Longus?

Answer 9

Quadratus Plantae

Question 10

Quadratus Plantae

Answer 10

Pulls tendon laterally

(Flex. Dig. Longus = medially)

O: Calcaneus

I: Flexor Digitorum Longus

A: Flex Toes

Question 11

Muscles of Foot - Layer 2

Flexor Hullucis Longus

Answer 11

Harry

Passes to distal phalanx of big toe, between two sesamoid bones

O: Fibula

I: Big toe

A: Flex big toe, inversion, plantar flexion of foot

Question 12

Muscles of Foot - Layer 3

Flexor Hallucis Brevis

Adductor Hallucis

Flexor Digiti Minimi Brevis

Answer 12

Flexor Hallucis Brevis: Two tendons, sesamoid bones in tendons

- - -

Adductor Hallucis:

Oblique/Transverse heads, Insert at Big Toe

Flexor Digiti Minimi Brevis: Small muscle to little toe (inside of layer 1)

Question 13

Muscles of Foot - Layer 4

Iterosseus

Answer 13

1. Dorsal Interossei - DAB

Doral - ABduct

2. Plantar Interossei - PAD

Plantar - ADduct

Question 14

What small foot muscles flex metatarsophalangeal joints and extend interphalangeal joints?

Answer 14

Interosseus muscles

Lumbricals

Question 15

Muscles of Foot - Layer 4 - Deep Tendons

Tendon of Peroneus Longus

Tendon of Tibialis Posterior

Answer 15

Tendon of Peroneus Longus:

Lateral to Medial, 1st metatarsal/medial cuneiform bones

- - -

Tendon of Tibiais Posterior:

Navicular, slips to cuneiform, cuboid, metatarsals 2-4

Question 16

What is the antagonist of the Peroneus Longus?

Answer 16

Tibialis Anterior

Question 17

Nerves and Arteries of Sole of Foot?

Answer 17

ANd

A - Posterior Tibial Artery

N - Tibial Nerve

Question 18

How does the posterieal tibial artery divide?

Answer 18

1. Lateral Plantar Artery
   - > Plantar Arterial Arch
   - > Plantar Digital Arteries
2. Medial Plantar Artery

Question 19

Tibial Nerve division in foot?

Answer 19

Medial and Lateral Plantar nerves

Both sensory and motor

Question 20

Medial Plantar Nerve and Lateral Plantar Nerve coverage on sole of foot?

Answer 20

Medial = Medial 3.5 digits / medial sole

Lateral = Lateral 1.5 Digits / lateral sole

Question 21

Innervation of Foot Muscles

Tibial Nerve’s Two Branches

Answer 21

Medial Plantar Nerve

1. Flexor Hallucis Brevis (Big Toe)
2. Abductor Hallucis (Big Toe)
3. Flexor Digitorum Brevis
4. First Lumbrical
   - - -

Lateral Plantar Nerve

Everything else

Question 22

Medial Longitudinal Arch

Answer 22

Highest arch

Responsible for ‘fallen arches’ (PES PLANUS)

Formed by: Calcaneus, talus, navicular, cuneiforms, and medial three metatarsal bones

Plantar Calcaneonavicular Ligament = SPRING ligament

Tibialis Posterior/Anterior insert to medial side

Question 23

Cause of Flat Feet (Pes Planus)

Answer 23

Weakening of Medial Longitudinal Arch

Stretching of Plantar Calcaneonavicular Ligament

Question 24

What type of muscles support the medial arch?

What type of muscles support the lateral arch?

Answer 24

Muscles that invert foot

- - -

Muscles that evert foot

Question 25

Lateral Longitudinal Arch

Answer 25

Smaller

Formed by calcaneus, cuboid, and lateral two metatarsals

Long Plantar Ligament and Plantar Aponeurosis

Peroneal Tendons

Question 26

Transverse Arch

Answer 26

Formed by cuneiform and cuboid bones and metatarsals

Supported by Interosseus Muscles and Peroneus Longus Tendon