Functional Anatomy 1 - Lecture 15: Ankle and Foot

tarsal bones (tarsus)

talus, calcaneus, navicular, cuneiforms, cuboid

talus

• articulates with the tibia and fibula superiorly

• articulates with the calcaneus inferiorly

• articulates with navicular bone anteriorly

talocrural joint

articulates with the tibia and fibula superiorly

• most superior

subtalar joint

articulates with the calcaneus inferiorly

talonavicular joint

articulates with navicular bone anteriorly

calcaneus

• inferior and posterior to talus

• articulates with talus superiorly

• articulates with cuboid anteriorly

• insertion for Achilles tendon

subtalar joint

articulates with talus superiorly

calcaneocuboid joint

articulates with cuboid anteriorly

navicular bone

medial, anterior to talus

• tuberosity of navicular

cuneiforms

medial, intermediate, lateral

• anterior to navicular

cuboid

• lateral

• anterior to calcaneus

metatarsals

1-5

• base (proximal)

• shaft

• head (distal)

phalanges

digit 1: proximal and distal

digits 2-5: proximal, middle and distal

rearfoot

talus and calcaneus

midfoot

navicular, cuboid, cuneiforms (3)

forefoot

MTs 1-5, phalanges 1-5

talus

• head: articulates with navicular

• neck: projects medially and anteriorly

• body

  • wider anterior (medial/lateral talar domes)

  • narrower posteriorly

• groove for flexor hallucis longus (FHL) tendon

• no muscle attachments

• essential in transmitting motion through rearfoot/ankle to LE

• stability via shape of body in talocrural joint

calcaneal tuberosity

attachment for Achilles tendon

• weight-bearing surface

sustentaculum tali

groove for FHL tendon inferior

fibular (peroneal) trochlea

• peroneus brevis superior

• peroneus longus inferior

lateral process of calcaneus

origin for abductor digiti minimi

medial process of calcaneus

origin for plantar fascia and abductor hullucis

navicular

• posterior articulation: talus

• anterior articulation: cuneiforms (all 3)

• lateral articulation: cuboid

• navicular tuberosity

  • attachment for tibialis posterior

• keystone of medial longitudinal arch

cuboid

• posterior articulation: calcaneus

• medial articulations

  • navicular (posteriorly)

  • lateral cuneiform (anteriorly)

• anterior articulation: base of MT 4 and 5

medial cuneiform

anteriorly articulates with base MT 1

intermediate cuneiform

anteriorly articulates with base with MT 2

lateral cuneiform

anteriorly articulates with base with MT 3

laterally articulates with cuboid

sesamoid bones

protect FHL tendon in weight-bearing positions

• medial and lateral

metatarsals

5 metatarsals

• base (proximal), shaft, head (distal)

  • head proximal side of metatarsophalangeal joint

• tuberosity of 5th MT

  • attachments for peroneus brevis

  • at lateral base of 5th mt

jones fracture

fracture at the base of 5th metatarsal

• near the tuberosity

• not very well vascularized, will take longer to heal

1st digit

proximal phalanx

• interphalangeal joint

distal phalanx

digits 2-5

• proximal phalanx

  • proximal interphalangeal joint

• middle phalanx

  • distal interphalangeal joint

• distal phalanx

ankle motions

• eversion/inversion

• dorsiflexion/plantarflexion

• adduction/abduction

talocrural joint

medial and lateral malleolus grip talus firmly (ankle mortise)

• requires distal tibiofibular joint stability

talocrural joint motion

• primarily ankle dorsiflexion and plantarflexion

• axis is slightly anterior/superior on medial side and posterior/inferior on lateral side

  • location of medial malleolus and lateral malleolus

subtalar joint

posterior articulation of the talus and calcaneus (primarily)

subtalar joint motion

inversion and eversion (of the subtalar joint)

subtalar joint motion in closed kinetic chain

• stj inversion transmits to tibial ER

• stj eversion transmits to tibial IR

transverse tarsal joint

aka midtarsal joint

• includes talonavicular and calcaneocuboid joints

transverse tarsal joint functions

• allows for flexibility of the forefoot based on the position of the rearfoot

• two joint axes working together

transverse tarsal joint motion

tri-planar, allows movement in all 3 planes

transverse tarsal joint motion, open chain

pronation: dorsiflexion, eversion, abduction

supination: plantarflexion, inversion, adduction

transverse tarsal joint motion, closed chain

pronation: more flexible foot

supination: more rigid foot

tarsometatarsal joints

• medial cuneiform with 1st metatarsal

• intermediate cuneiform with 2nd metatarsal

• lateral cuneiform with 3rd metatarsal

• cuboid with 4th and 5th metatarsal

all plane joints, limited motion in all!

metatarsophalangeal joints

MT 1-5 with respective proximal phalanx 1-5

• synovial, condyloid joints

metatarsophalangeal joint motion

flexion/extension, abduction/adduction, 1st MTP extension plays significant role during gait

interphalangeal joints

1st interphalangeal joint

2-5: DIP and PIP

• synovial, hinge joints

interphalangeal joint motion

flexion/extension

medial longitudinal arch

calcaneus, talus, navicular, 3 cuneiforms, medial 3 metatarsal bones

arches of the foot

medial longitudinal, lateral longitudinal, transverse

lateral longitudinal arch

calcaneus, cuboid, lateral 2 metatarsal bones

transverse arch

tarsometatarsal joints

pes cavus

increased medial longitudinal arch height, higher arch

pes planus

decreased medial longitudinal arch height, lack of arch

lateral collateral ligaments

anterior talofibular ligament, calcaneofibular ligament, posterior talofibular ligament

anterior talofibular ligament (ATFL)

• flat, weaker band

• lateral malleolus to neck of talus

calcaneofibular ligament (CFL)

• round, cord-like

• lateral malleolus to lateral calcaneus

posterior talogibular ligament (PTFL)

• thick, strong band

• malleolar fossa of fibula to lateral tubercle of talus

inversion

ligaments in lateral rearfoot resist ________ of the rearfoot

plantarflexed

ATFL resists inversion more in _____________ positions

neutral/dorsiflexed

CFL resists inversion more in _____/________ positions

dorsiflexed

PTFL resists inversion more in ______________positions

lateral ankle sprain

• inversion ankle sprain

• anterior drawer test for the ankle

ligaments in medial rearfoot

medial collateral ligaments

• anterior tibiotalar

• tibionavicular

• tibiocalcaneal

• posterior tibiotalar

anterior tibiotalar

medial malleolus to anterior talus

tibionavicular

medial malleolus to navicular

tibiocalcaneal

medial malleolus to medial calcaneus

posterior tibiotalar

medial malleolus to posterior talus

medial collateral ligaments function

• all resist eversion

  • anterior resist more in plantarflexed position

  • posterior resist more in dorsiflexed position

plantar ligaments

plantar fascia/aponeurosis

plantar fascia/aponeurosis

thick, superficial fascia

• calcaneus to heads of metatarsals 1-5

• superficial to muscles

plantar fascia/aponeurosis function

supports plantar foot and medial longitudinal arch

long plantar ligament

• calcaneal tuberosity to base of MTs 2-5

• strong ligament, supports the lateral longitudinal arch

• helps protect peroneus longus tendon

short plantar ligament

• AKA calcaneocuboid ligament

• calcaneal tubercle to cuboid

plantar ligaments

long plantar, short plantar, spring

• very deep, remove 4 layers of muscle

spring ligament

• AKA plantar calcaneonavicular ligament

• broad, thick ligament

• sustentaculum tali to plantar surface of navicular

• connection from calcaneus to navicular

• function

  • helps maintain medial longitudinal arch

dorsal ligaments

talonavicular, bifurcate

talonavicular ligament

• superior/anterior talus to superior navicular

• connects bones and prevents anterior/inferior displacement of navicular

bifurcate ligament

• Y-shaped ligament

• superior/lateral calcaneus to cuboid and navicular

collateral ligaments

MTPs and IPs

• resists abduction/adduction

plantar ligament (plate)

• resists hyperextension

• turf toe: first MTP injured (excessive hyperextension)

deep transverse ligament

• between MT heads horizontally

• resists separation of MTs

1st layer of intrinsic foot muscles

• abductor hallucis

• flexor digitorum brevis

• abductor digiti minimi

2nd layer of intrinsic foot muscles

• quadratus plantae

• tendon for FDL

• lumbricals (1-4)

• tendon for FHL

3rd layer of intrinsic foot muscles

• flexor hallucis brevis (FHB)

• adductor hallucis (transverse and oblique heads)

• flexor digiti minimi brevis

4th layer of intrinsic foot muscles

• plantar interossei

• dorsal interossei

abductor hallucis

O: medial tubercle calcaneal tuberosity

I: medial side of base of 1st proximal phalanx

A: abducts 1st digit at MTP

N: medial plantar n (L5-S1)
B: medial plantar a.

flexor digitorum brevis

O: medial tubercle calcaneal tuberosity

I: both sides middle phalanges of digits 2-5

• split allows for tendon FDL to pass through and distal

A: flex digits 2-5 at MTP and PIP

N: medial plantar n. (L5-S1)

B: medial and lateral plantar a.

abductor digiti minimi

O: medial and lateral tubercles calcaneal tuberosity

I: lateral side of base of 5th proximal phalanx

A: abducts 5th digit at MTP

N: lateral plantar n. (S1-S3)

B: lateral plantar a.

quadratus plantae

O: medial and lateral plantar calcaneus

I: lateral side of FDL tendon

A: assist FDL in flexion of digits 2-5 at DIP, PIP, and MTP

• adjusts the line of pull for FDL

N: lateral plantar n. (S1-S3)

B: lateral plantar a.

lumbricals

O: tendon of FDL

I: extensor hood/expansion digits 2-5

A: flexion MTP digits 2-5, extension PIP and DIP digits 2-5

N:

• medial 1: medial plantar n (L5-S1)

• lateral 3: lateral plantar n. (S1-S3)

B: medial and lateral plantar a.