Ankle Lecture Flashcards
when is the foot a mobile adapter?
at heel strike
when is the foot a rigid lever?
at push off
what makes up the rearfoot?
the talus and calcaneous
what makes up the midfoot?
navicular, cuneiforms, cuboid
what makes up the forefoot?
metatarsals and phalanges
what are the axes of the talocrural jt?
14 deg inferior to the transverse plane
23 deg posterior to the frontal plane
what is the “true ankle jt”?
talocrural jt
what are the actions of the talocrural jt?
DF and PF
how much DF is available at the talocrural jt?
26 deg
how much PF is available at the talocrural jt?
48 deg
what are the 3 articulations of the subtalar jt?
anterior, middle, and posterior talocalcaneal articulations
what structures divides the subtalar jt?
tarsal tunnel
what are the main motions of the subtalar jt?
inversion and eversion?
what are the axes of the subtalar jt?
42 deg superior to the transverse plane
16 deg medial to the sagittal plane
what is the mitered hinge of the ankle?
when the tibia moves in the transverse plane, the foot moves in the frontal plane
when the tibia moves into IR, what does the foot and femur do?
the foot goes into pronation
the femur goes into IR
when the tibia moves into ER, what does the foot and femur do?
the foot goes into supination
the femur goes into ER
what is the main motion of the talonavicular jt of the midtarsal jt?
PF/DF
what are the two articulations of the midtarsal jt?
the talonavicular jt
the calcaneocuboid jt
when the axes of the midtarsal jt are crossed, is it more stiff or more loose?
stiffer
when the axes of the midtarsal jt are parallel, is it more stiff or more loose?
looser
t/f: the midtarsal jt can contribute to DF/PF
true
what is the position of the foot at heel strike?
inverted heel that immediately everts from ground reaction forces
what is the triplanar motion of pronation?
DF
eversion
abd
what is the triplanar motion of supination?
PF
inversion
add
what does the interosseous ligament do?
holds the tibia and fibula together
what happens to the interosseous lig with PF?
it naturally stretches some as the tibia and fibula separate some
when the ankle rotates and goes into PF, what is there risk for?
high ankle sprain
what is the LEFS?
20 item self assessment of functional activities
items rated 0-4 on difficulty
score is a sum of the responses with a max score of 80
what is the MDC and MCID for the LEFS?
9 points
what item are a part of the historical interview?
past medical hx, occupation and activities, meds, diagnostic tests, pain level/pattern/duration
what are the various MOIs for ankle injuries?
macrotrauma
microtrauma (instrinsic, extrinsic, combo)
what is the MOI of lateral ankle sprains?
inversion and PF
t/f: plantar fasciitis is usually a cumulative trauma
true
when there is increased valgus, is there increased pronation or supination?
protation
what is the most injured ligament in the body?
anterior tibiofibular ligament (ATF lig)
what should we observe for in an ankle exam?
foot type
callus pattern
nails
skin (capillary refill and pulse)
swelling
scars
deformities
footwear
what is pes cavus?
a high arched foot with a high navicular in the Feis line
what is pes planus?
a flat foot with a drop in the navicular in the Feis line
what is normal inversion of the rearfoot?
6-8 deg
when there is increased inversion of the rearfoot, what is this called?
rearfoot varus
what foot abnormality makes it take longer for the rearfoot to get into the correct position in gait due to increased inversion?
rearfoot varus
t/f: normally the metatarsal heads should be in the same plane as the calcaneal condyles
true
what is rearfoot varus?
increased rearfoot inversion that causes the foot to stay pronated longer and gives less supination
increased rearfoot inversion in NWB and looks everted in WB
what is forefoot varus?
when the metatarsal head are further up on the medial side (inverted metatarsals) and the foot stays pronated for too long
forefoot varus puts stress on what structures?
post tib
plantar fascia
peroneus longus
what happens at the knee with forefoot varus?
knee valgus
how does the talus move in relation to the tibia?
they move together
when the talus pronates (moves down and in) what does the tibia do?
the tibia rotates in and down a little
when the talus pronates (moves down and in) what does the knee do?
likely to go into valgus
when the talus supinates (moves up and out) what does the tibia do?
the tibia rotates out and up a little
when the talus supinates (moves up and out) what does the knee do?
likely to go into varus
t/f: forefoot valgus is common
false
what is forefoot valgus?
when the lateral aspect of the foot is up and the medial aspect is down
foot has increased supination and decreased time in pronation
what foot abnormality causes the medial foot to hit the ground sooner than it should when pronating?
forefoot valgus
what is the risk with forefoot valgus?
ankle sprain
t/f: forefoot valgus causes an unstable ankle bc the foot isn’t becoming a mobile adapter
true
t/f: the foot is more inverted with forefoot valgus
true
what other foot abnormality may mimic forefoot valgus?
PF of the 1st ray
with PF of the 1st ray, what is the risk to the ankle?
lateral ankle sprains bc the medial side of the foot is hitting soon than it should and puts stress on the lateral ankle
what is forefoot valgus?
an overly supinated foot
why is a pronated foot looser?
bc it causes the axes of the midtarsal jt to line up
what causes calluses?
friction bw the bone and the skin that increases keratinization
what is a claw toe?
DF MTP
PF IPs
where are the calluses with a claw toe?
on the top of the PIP and the bottom of the MTP
when does claw toe often occur?
when the foot in unstable from overpronation
what is a hammer toe?
hyperext MTP
flex IPs
what is a mallet toe?
flexed DIP
what is the too many toes sign a sign of?
post tib tendinitis
why do we check callus patterns on the feet?
they give reliable clues of the biomechanical response of the foot in fxn
when someone has calluses on the medial and lateral ball of their foot, what does this tell us?
they may have a valgus foot and PFed 1st ray
the foot is hitting the medial side early and throwing the foot out laterally
what is a callus of the medial great toe?
pinch callus
if someone has a rearfoot varus, what might the callus patterns look like?
increased thickness across the 2nd >3rd met head w/little to no shear over the 1st and 5th met head
why is there increased thickness across the 2nd >3rd met head w/little to no shear over the 1st and 5th met head in rearfoot varus?
bc the amount of pronation produces instability late in midstance as the foot remains partially pronated. this hypermobility prevents the 1st ray from being stabilized
t/f: athletic tape on the arch may help with overpronation
true
what is the low-dye taping technique?
taping the arch of the foot for overpronation, or plantar fasciitis
how do insoles work?
they seem like arch support, but really are trying to control the foot by making the thickness of the sole higher or lower to prevent pronation/supination
how do we measure the density of foam in insoles?
durometers
what is a straight last often for?
medial support
who often uses very curved lasts?
sprinters
what are the types of lasts?
straight, semi-curved, very curved
what is the last of a shoe?
the shape of the sole of the shoe
what are the benefits of zero drop heels?
they allow increased splaying of the foot for better balance
strengthens the intrinsic muscles of the foot
what are the items involved in the neuromuscular screen for the foot and ankle?
dermatome testing for sensation
DTRs (Achilles reflex)
circulation (capillary refill)
girth (figure 8)
how much DF is there at the ankle?
10-20 deg
how much PF is there at the ankle?
45-50 deg
how much inversion is there at the ankle?
30 deg
how much eversion is there at the ankle?
20 deg
how can you take out the gastroc to measure DF?
by flexing the knee
what is the concave surface of the distal tibiofibular joint?
tibia
what is the convex surface of the distal tibfib jt?
fibula
what is the arthrokinematics of the distal tibfib jt in DF?
tib and fib separate as the talus enters the jt
fib glides sup
what is the arthrokinematics of the distal tibfib jt in PF?
tib and fib return to neutral
what is the concave surface of the talocrural jt?
distal tib/fib
what is the convex surface of the talocrural jt?
talus
what is the arthrokinematics of the talocrural jt in OKC DF?
talus rolls ant, glides post
what is the arthrokinematics of the talocrural jt in CKC DF?
tibia rolls and glides ant
what are the arthrokinematics of the talocrural jt in OKC PF?
talus rolls post, glide ant
what are the arthrokinematics of the talocrural jt in CKC PF?
talus rolls and glides post
what is the concave surface of the subtalar jt?
ant calcaneal facet and post talus
what is the convex surface of the subtalar jt?
post calcaneal facet and ant talus
what are the arthrokinematics of the subtalar jt in OKC inversion?
ant calcaneal facet rolls and glides med
post calcaneal facet rolls and glides lat
what are the arthrokinematics of the subtalar jt in CKC inversion?
talus rolls med, glides lat on ant calcaneal facet while the talus rolls and glides med on post calcaneal facet
what are the arthrokinematics of the subtalar jt in OKC eversion?
ant calcaneal facet rolls and glides lat while the post calcaneal facet rolls and glides med
what are the arthrokinematics of the subtalar jt in CKC eversion?
talus rolls lat and glides med on ant calcaneal facet while talus rolls and glides lat on post calcaneal facet
what are the 2 midtarsal jts?
talonavicular and calcaneocuboid jts
what is the concave surface of the talonavicular jt?
navicular
what is the convec surface of the talonavicular jt?
talus
what type of jt is the calcaneocuboid jt?
saddle jt
what are the arthrokinematics of the midtarsal jt in DF and inversion?
navicular and cuboid glide dorsally on the talus and calcaneous respectively
what are the arthrokinematics of the midtarsal jt in PF and eversion?
navicular and cuboid glide plantarly on talus and calcaneous respectively
what is the concave surface of the MTPs?
phalynx
what is the convex surface of the MTPs?
metatarsal
what are the arthrokinematics of MTP flexion?
phalynx rolls and glides plantarlly on the proximal phalynx
what are the arthrokinematics of MTP extension?
phalynx rolls and glides dorsally on the proximal phalynx
the foot should have ____ mobility when innverted/supinated?
decreased
the foot should have ____ mobility when everted/pronated?
increased
is a foot that DF and everts when asked to point foot up normal or abnormal?
abnormal
what is the anterior drawer test sensitivity and specificity?
sn=78%
sp=75%
what is the anterior drawer test a test for?
lateral ankle sprain (ATF lig)
what a (+) anterior drawer test of the ankle?
pain/hypermobility
what is the technique for the anterior drawer test of the ankle?
hold the tib/fib and pull up on the calcaneous with a bit of PF
if we want to test for hypermobility, what do we have to do?
do the special tests bilaterally to get a sense for the person’s normal
what grade ankle sprain would likely produce very little pain and lots of extra motion?
grade 3 sprain
what grade ankle sprain would likely produce lots of pain and lots of extra motion?
grade 1-2 sprains
what is the sensitivity and specificity of the talar tilt test?
sn=67%
sp=75%
what is the talar tilt test a test for?
lateral ankle sprain (ATF, some calcaneofib, and maybe some talofib lig)
what is a positive talar tilt test?
pain/laxity
what is the technique for the talar tilt test?
grab the calcaneous and shift the grip anteriorly to move the calcaneous, cuboid, and 5th metatarsal medially
what is the sensitivity and specificity of the squeeze test?
NA
what is the squeeze test a test for?
syndesmotic sprain, high ankle sprain, ATF sprain
what is a (+) squeeze test?
pain
what is the technique for the squeeze test?
at the mid to distal calf, squeeze the tib and fib together
what is the sensitivity and specificity of the ER test?
sensitivity=NA
specificity=95%
what is the ER test a test for?
high ankle sprain?
what is a (+) ER test?
pain and laxity
what is the technique for the ER test?
take the calcaneous and talus into ER in the mortis to separate the mortis
what is the Thompson test a test for?
a full Achilles tear
what is the sensitivity and specificity for the Thompson test?
sn=40-96%
sp=NA
what is the technique for the Thompson test?
in prone, w/the foot off the edge of the table, squeeze the calf and the foot should PF
what is a (+) Thompson test?
if the foot doesn’t move when you squeeze the calf
if there is a partial Achilles tear, will the Thompson test be positive?
probably not
what is the sensitivity and specificity for the impingement sign?
sn=95%
sp=88%
what is the impingement sign a test for?
ankle impingement???
lateral ankle sprain
what is the technique for the impingement sign?
in sitting/supine, block the talus with the thumb of one hand and evert the foot w/a little DF with the other hand
what is a (+) impingement sign?
pain
what is the sensitivity and specificity of the Windlass test?
sn=13.6-31.8%
sp=100%
what is the Windlass test a test for?
plantar fasciitis, hallux limitus, flexor hallicus longus tendinopathy
what is normal DF of the great toe?
65 deg (more in runners)
what is the technique for the Windlass test?
stabilize the first ray from the medial side of the foot with one hand and DF the great toe with the other hand in neutral and DF with some inversion to lock up the midtarsal jt
OR can also do in standing
what is a (+) Windlass test?
pain and tightness
what is the sensitivity and specificity for the Morton test?
sn=NA
sp=NA
what is the Morton test a test for?
Morton’s neuroma (a balled up nerve that becomes sensitive bw the metatarsals)
what is the technique for Morton’s test?
squeeze the metatarsals together
what is a (+) Morton test?
plantar pain in the foot and numbness midfoot distal
what is the sensitivity and specificity of the Tinel test?
sn=58%
sp=NA
what is the Tinel test a test for?
nerve irritation or damage of the nerve in the tarsal tunnel bw the medial malleolus and calcaneous
what is the technique for the Tinel test?
tap on the nerve outside the medial malleolus
what is a (+) Tinel test?
numbness and tingling along the nerves distribution
what is the sensitivity and specificity of the calcaneal bump test?
sn=NA
sp=NA
what is the calcaneal bump test a test for?
fx or high ankle sprain
what is the technique of the calcaneal bump test?
push up on the calcaneus to compress it into the tibfib
what is a (+) calcaneal bump test?
pain in the calcaneous (fx)
pain in the high ankle (sprain)
what is the purpose of the Ottowa ankle and foot rules?
to decide whether or not a radiograph is indicated
what are the Ottowa ankle rules?
tender at the posterior edge of the distal 6cm of medial malleolus
tender at the posterior edge of 6cm of the lateral malleolus
unable to WB for 4 steps
what is the sn and sp of the Ottowa ankle rules?
sn=95-100%
sp=16%
t/f: if any one of the Ottowa ankle and foot rules are positive, a radiograph is indicated
true
if all 3 Ottowa ankle or foot rules are negative, is a radiograph indicated?
nope
t/f: a stress fx may not immediately show up on imaging, so if the pt still can’t WB after a few days, send for another image
true
what are the Ottowa foot rules?
tender at the navicular
tender at the base of the 5th metatarsal
unable to WB for 4 steps
what is the sn and sp of the Ottowa foot rules?
sn=93-100%
sp=12-21%
