Foot Flashcards
bones of foot
- tarsals
- metatarsals (1/digit)
- phalanges (proximal/middle/distal)
tarsal bones
- calcaneus (heel)
- talus
- cuneiform (lateral + intermediate + medial)
- cuboid
- navicular
my insanely large cucumber never touches carrots
sesamoids
@sole/plantar foot, MT1
2 of them-forms within tendons of flexor hallucis brevis muscle
foot divisions
- forefoot (phalanges + MTs)
- midfoot (cuneiforms + cuboid + navicular)
- hindfoot = calcaneus + talus
- tarsus = all tarsals (midfoot + hindfoot)
joints
tarsometatarsal/lisfranc = div fore/mid foot
trasverse tarsal/midtarsal = div mid/hintfoot
talus structure
head
neck
trochlea “pulley”
calcaneus bony features
calacneal tuberosity = achilles tendon insert, most weight bearing
articular surfaces= for cuboid bone and talas (@post, middle, anterior)
-sustentaculum tali/talar shelf: support head of talus and has groove for flexor hallucis longus tendon
superficial fascia + skin
thin + loose CT fascia
dorsum = not much fat, thin skin, fewer lymph vessels
sole = fat lobules in compartments separated by dense CT,
dorsum is more susceptible to edema than sole near lat malleolus
deep fascia
aka dorsalis fascia
cont w/ crural and plantar fascia
very thin except where extensor retinacula
tendons/arteries/nerves from ant leg run deep to dorsalis fascia
compartments
- dorsal
- interosseous
- medial (sole)
- central (sole)
- lateral (sole)
interosseous compartment
boundaries: surrounded by dorsal + plantar interosseous fascia
has MT bones + dorsal and plantar interosseous muscles + deep plantar and deep MT vessels
dorsal compartment
boundaries: dorsal fascia + tarsal bones + dorsal interosseous fascia of mid/forefoot
contents: muscles + neurovasculature
foot muscles
intrinsic
20 intrinsic (og on foot > in distally on foot)
- 2 dorsal
- 4 intermediate
- 14 plantar/sole
extrinsic muscles
- extensor hallucis longus (will split 3 ways)
- extensor digitorum longus
extend toes + assist dorsiflexion
og @ant leg > cross ankle > insert on foot so only tendons in dorsum/sole
both og in anterior compartment
intrinsic dorsum muscles
- extensor hallucis brevis (distally)
- extensor digitorum brevis (II-IV proximally)
both og @ superolateral surface of calcaneus > EDB will insert on EDL
inn by deep fibular N
blood by dorsalis pedis A (+branches= arcuate, lateral tarsal, fibular A)
deep fibular nerve
sciatic > common fib > deep fibular/peroneal N
-lateral branch (motor only) + medial branch (motor and cut, runs w/ dorsalis pedis A and MT1 A)
supplies muscles of anterior leg then cross under extensor retinacula to supply both intrinsic and extrinsic dorsum muscles
cutaneous innervation
- saphenous N (from femoral, medial ankle)
- lateral dorsal cutaneous (from sural N)
- superficial fibular (from common fib, majority of dorsum, flip flops)
- deep fibular (from common fib, flip flop triangle b/t I and II)
superficial fibular N
branches into medial + intermediate dorsal cut N > common > proper dorsal digital N
motor = fibularis longus and brevis, eversion bc @lateral leg
cutaneous = distal 1/3 @anterolateral leg and most dorsum
dermatome testing
L4/L5/S1 test on medial/middle/lateral respectively with filament
also test cutaneous superficial fibular nerve same way
arteries
anterior tibial A > dorsalis pedis A as cross ankle
branches:
-1 lateral tarsal A (big guy)
-2 medial tarsal A
-arcuate A (big, ARCs across to join lateral)
-deep plantar (to sole, deep plantar arch)
-1st dorsal metatarsal A
1st dorsal metatarsal A
to medial side of digit I
ends by splitting into 2nd and 3rd dorsal digital As
arcuate A branches
- 3 dorsal metatarsal As > each give off 2 dorsal digital As (digits II-IV)
- 10th dorsal digital A to lat side of digit V
anastomoses w/ 3 perforating branches of deep plantar arch
terminates in anastomosis w/ lateral tarsal A
dorsalis pedis pulse
runs lateral to EHL tendon but not easy to find
weak/absent can suggest blockage of anterior tibial or vascular insufficiency from peripheral arterial disease
5 P’s of acute arterial occlusion
- pain
- pallor
- paraesthesia
- paralysis
- pulselessness
deep veins
deep to dorsalis fasica in accompanying vein form
flow greatly improves when walking or moving feet
superficial veins
superficial to dorsalis fascia but not paired
1.10 dorsal digital >
2.4 dorsal metatarsal >
3.dorsal venous arch >
4.medial marginal (>great saph) + lateral marginal (>lesser saph)
dorsal venous network highly variable
lymphatic drainage