Lower leg and Ankle Anatomy Flashcards
tibia
primary weight bearing bone
4 compartments lower leg
anterior (most common place for compartment syndrome): dorsiflexors and toe extensors
TA, EHL, EDL, fibularis tertius, anterior tibial artery → dorsalis pedis artery in foot, deep fibular n.
lateral: plantar flexors and evertors
fibularis longus, fibularis brevis, superficial fibular n.
superficial: plantar flexors
gastroc, soleus, plantaris
deep: invertors and toe flexors
TP, FDL, FHL, posterior tibial a., tibial n.
all of these pass through the tarsal tunnel to enter the plantar surface of the foot.
ankle ligaments
ATFL: most commonly injured, prevents anterior translation talus/foot; anterior drawer test
CFL: 2nd most commonly injured in lateral ankle sprain, fibularis longus/brevis tendons run over it
PTFL: almost never torn
deltoid: medial ankle stabilizer, triangular ligament
tibiofibular syndesmosis: interosseous ligament
ankle plantarflexion (musc, inn)
gastrocnemius: S1-2 tibial n.
soleus: S1-2, tibial n.
plantaris
tibilaris posterior: L5-S1, tibial n.
FDL, FLD, fib long, fib brev also contribute (toe flexors), mainly evertors
ankle dorsiflexion (musc, inn)
tibialis anterior: L4-5, deep fibular n.
fibularis tertius: L5-S1, deep fibular n.
EHL, EDL also contribute; main action is to extend toes
ankle inversion (musc, inn)
tibialis posterior: L5-S1, tibial n.
tibialis anterior: L4-5, deep fibular n.
ankle eversion (musc, inn)
fibularis longus and brevis: L5-S1, superficial fibular n. (main evertors)
fibularis tertius: L5-S1, deep fibular n.
ankle pronation and supination (movements involved)
pronation: eversion, dorsiflexion, external rotation of tibia
supination: inversion, plantar flexion, internal rotation of tibia
Maisonneuve fracture
high ankle sprain complication - proximal fibular fracture (rupture of tibiofibular syndesmosis)
syndesmosis splits → extends up → proximal fibular fracture
order XR to r/o fracture
shin splints
medial tibial stress syndrome, medial shin pain
excessive overload over time (running) → microtears of muscle-periosteum interface (traction periositis)
Tx: correct pronation
tibial stress fracture
d/t untreated shin splints
actual microfracture of tibia d/t overuse
reimage to follow fracture healing
talus fracture
fracture of bone that articulates w tibia, usually d/t forced dorsiflexion w axial load
talar body fracture (AKA dome) have greater risk of AVN
Tx: NWB if non displaced, ORIF otherwise
calcaneus fracture
MC foot fracture d/t traumatic axial load
Tx: cast and NWB if stress fx or small fx; otherwise ORIF
most common foot fracture
calcaneus fracture
Sever’s disease
posterior heel pain in children d/t excessive overuse of gastroc (achilles tendon) pulling on calcaneus → calcaneal aopohysitis
posterior heel pain in athletic child
sever’s disease
overuse injury w achilles pulling on calcaneus → calcaneal apophysitis
syndesmosis injury
high ankle sprain, injury of tibiofibular syndesmosis (interosseous membrane) d/t excessive external rotation forces; common football injury
talus pushes into fibular → separation, tearing ligaments
sometimes causes Maisonneuve fracture
squeeze test positive
Tx: NWB CAM boot 3 wks
lateral ankle sprain
injury to ATFL/CFL/PTFL d/t excessive inversion forces
rolling ankle inward
most common type and mechanism of ankle sprain
grading 1-3; ATFL/CFL tears
beware fibularis longus/brevis tendon injury
anterior drawer (ATFL) and talar tilt (CFL) positive
most common ankle sprain
lateral ankle sprain (ATFL/CFL/PTFL)
order of torn ligaments is usually ATFL→CFL→PTFL
grading of lateral ankle sprains
1: partially torn ATFL, intact CFL
2: fully torn ATFL, partially torn CFL
3: fully torn ATFL, fully torn CFL
lateral ankle sprain, common co injury
beware fibularis longus/brevis tendon injury
medial ankle sprain
deltoid ligament (very sturdy) injury d/t excessive eversion
not common bc deltoid ligament strong
deltoid ligament: anterior and posterior tibiotalar ligaments, tibionavicular ligament, tibiocalcaneal ligament
deltoid ligament structures
very strong ligament, eversion injury uncommon
components: anterior and posterior tibiotalar ligaments, tibionavicular ligament, tibiocalcaneal ligament
tarsal tunnel syndrome
pain/numbness/tingling d/t compression of structures underneath the flexor retinaculum
region behind median malleolus, invovling structures that pass underneath the flexor retinaculum (tarsal tunnel)
tibial n/a/v, TP, FDL, FHL
tarsal tunnel acronym
Tom Dick and Very Nervous Harry
tibial n/a/v, TP, FDL, FHL
ankle bursitis
Haglund deformitiy AKA “pump bump”
excessive friction forces (high heels)
bursae: retrocalcaneal, retroachilles
Haglund deformity
AKA “pump bump”
ankle bursitis d/t friction forces, usually high heels
ACS of leg
emergency fasciotomy indicated
usually anterior compartment
trauma → venous damage → blood pumps in but can’t pump out → ischemia/necrosis
extreme out of normal proportion pain stretching muscles of that compartment
w/u: manometry (compartment pressure testing)
chronic exertional compartment syndrome
chronic condition, temporarily raised intracompartmental pressure during exercise
pain/paresthesias/weakness worse or increased intensity w exercise
Dx: manometry
Tx: fasciotomy
TA tendon injury
overuse (tenosynovitis) or rupture (eccentric overload) → TA tendon (dorsiflexor/invertor) injury
foot slap may be audible/visible
pain w resisted dorsiflexion or passive plantarflexion w tendon palpation
tibialis posterior tendon injury
overuse; TP is plantar flexor and invertor
higher risk w gait abnormalities, excessive pronation, medial ankle sprains (deltoid ligament sprain, rare)
remember TP wraps around medial malleolus
too many toes sign
FHL injury
dancer’s tendonitis
actions w lots of big toe flexion against resistance (dancing) → FHL (long big toe flexor) injury
fibularis tendon injury
often d/t overuse eversion activity (overpronation, sports) or as result of bad lateral ankle sprain
pain w resisted plantar flexion and eversion, or passive dorsiflexion and inversion
achilles tendon injury
pain posterior heel over achilles tendon and calcaneus d/t repetitive eccentric overload → inflammation and degeneration
risk of tendonosis (degredation d/t improper healing)
distal 2-6 cm of achilles tendon is poorly vascularized → predisposed to tears
