Anatomy - Foot Flashcards
26 bones of the foot
- Tarsal (7 bones)
i. Calcaneum
ii. Talus
iii. Navicular
iv. Cuboid
v. Cuneiform (middle, intermediate, lateral) - Metatarsal (5 bones)
(first to fifth) - Phalanges (14 bones)
(proximal, middle, distal)
*except first phalanges, has no intermediate
Tibialis anterior insertion?
Base of first metatarsal (plantar aspect)
Extensor hallucis longus insertion?
Base of first distal phalange toe
Extensor hallucis brevis insertion?
Base of first proximal phalange toe
Extensor digitorum longus insertion?
Base of proximal and middle phalanx of 2nd to 5th toes
Extensor digitorum brevis insertion?
Anterior surface of calcaneal body
Peroneus brevis and tertius insertion?
Base of fifth metatarsals (Dorsal aspect)
Flexor hallucis longus insertion?
Base of distal phalange of first toe
Flexor hallucis brevis insertion?
Base of proximal phalange of first toe
Flexor digitorum longus insertion?
Base of distal phalanx of 2nd to 5th toes
Flexor digitorum brevis insertion?
Body of middle phalanx of 2nd to 5th toes
Layers of the sole of the foot?
- Skin
- Deep fascia (plantar aponeurosis)
- Muscles of the foot
(4 layers)
First muscular layer of foot?
- Abductor hallucis
- Flexor digitorum brevis
- Abductor digiti minimi
Second muscular layer of sole foot?
- Quadratus plantae
- Lumbricals
- Flexor digitorum longus
- Flexor hallucis longus
Third muscular layer of sole foot?
- Flexor hallucis brevis
- Adductor hallucis
- Flexor digiti minimi
Fourth muscular layer of sole foot?
- Interossei
- Peroneus longus
- Tibialis posterior
Sole muscles supplied by medial plantar nerve?
- Abductor hallucis
- Flexor hallucis brevis
- Flexor digitorum brevis
- First interossei
(Others are by lateral plantar)
*Both are branch of tibial nerve
Arterial supply of plantar foot?
- Medial plantar artery
- Lateral plantar artery
(Both from posterior tibial artery)
Plantar fascia origin and insertion?
Origin - medial calcaneal tuberosity
Insertion -
i. base of 5th metatarsal (lateral band)
ii. base of all proximal phalanx
Function of plantar fascia?
- Protects above muscles, nerve, arteries
2. Medial arch support
Bones and joints of hindfoot
Bones
- talus
- calcaneus
Joints
- Subtalar: inversion, eversion
- Transverse tarsal (Chopart): works with subtalar
- made up of talonavicular, calcaneocuboid joints
- inversion cause bone to locked
- eversion cause bone to unlocked (allow conformity to ground surface)
Bones and joints of midfoot
Bones
- cuneiform (3)
- navicular
- cuboid
Joints
- Naviculocuneiform
- Intercuneiform
- Tarsometatarsal (Lis Franc)
Lis Franc joint?
Has 3 columns:
- Medial: 1st meta, medial cuneiform, navicular
- most load on standing - Middle: 2nd and 3rd meta, middle, lateral cuneiform
- least mobile, allow rigidity during push-off - Lateral: 4th and 5th meta, cuboid
- most mobile, allow walking on uneven ground
Supported by 3 ligaments:
- Dorsal tarsometatarsal layer: weakest
- Interosseus/Lis Franc ligament: strongest
- Plantar tarsometatarsal layer: 2nd strongest
- Intermetatarsal ligament: between 2nd to 5th metatarsal bases
Origin and insertion of Lis Franc ligament?
Origin: Medial cuneiform plantar
Insertion: Base of 2nd metatarsal
Function:
- stabilize 2nd metatarsal
- maintains roman/modfoot arch
Bones and joints of forefoot?
Bones
- metatarsal
- phalanges
Joints
- MTP
- Proximal IP
- Distal IP
Dorsum of foot
1 artery forms 3 branches 1 nerve 1 venous arch from 2 veins 2 muscles 4 tendons
Artery Dorsalis pedis forms - first dorsal metatarsal - arcuate - lateral tarsal
Veins
Dorsal venous arch from
- great saphenous vein (medial)
- small saphenous vein (lateral)
Nerve
- Deep peroneal nerve
Muscles
- Extensor hallucis brevis
- Extensor digitorum brevis
Tendons
- Tibialis anterior
- Extensor hallucis longus
- Extensor digitorum longus
- Peroneus tertius
Tibialis posterior insertion
- Anterior limb to
- navicular tuberosity
- medial cuneiform - Middle limb to
- middle and lateral cuneiform
- cuboid
- 2nd to 4th metatarsal - Posterior limb to
- sustentaculum tali
Talus articulation surfaces
- Inferior surface: posterior facet of calcaneus
- Talar head: navicular bone
- Lateral process: lateral malleolus, posterior facet of calcaneus
- Posterior process: groove for FHL
4 Talus blood supply
- Posterior tibial artery -> artery of tarsal canal (most important) -> talar body
- Deltoid artery -> talar body
- Anterior tibial artery -> head, neck of talus
- Perforating peroneal artery -> artery of tarsal sinus -> head, neck of talus
Sesamoid bone
- Two sesamoid bone below head of 1st metatarsal
- tibial/medial sesamoid
- fibular/lateral sesamoid - Function
- reduce friction at metatarsal head
- protect FHL (in between)
- weight bearing - Attachment
- FHB to both sesamoid
- Adductor hallucis to tibial
- Abductor hallucis to fibular
