Ankle/ Foot Flashcards
Describe the functions of the foot and ankle.
Weight-bearing.
Set up BOS that enables balance, foot serves as rigid lever for push in ambulation,
accommodation and shock absorption in ground contact
List the joints of the ankle/foot complex.
talocrural(true ankle joint), proximal and distal tib fib, subtalar,transverse tarsal joint, tarsometatarsal, metatarsal phalangeal, and interphalangeal
list the functional segments of the foot
hindfoot,midfoot, forefoot
what bones make up the hindfoot?
calcaneus and talus
what bones make up the midfoot?
cuboid, navicular and cuneiforms
what bones make up the forefoot?
metatarsals and phalanges
What is the closed-packed position of the proximal and distal tibiofibular joints?
maximal dorsiflexion
What is the open-packed position of the proximal and distal tibiofibular
joints?
10 degrees of plantarflexion
clinical app: high ankle sprain, syndesmotic ankle sprain
occurs when talus is forcefully LATERALLY rotated w/in ankle mortise; stretching or tearing of interosseous membrane or ant/post distal tibfib ligament
what are the limited motions of the proximal and distal tib fib joint?
ant/post glide
sup/inf glide
IR/ER
what is the function of the medial collateral (deltoid) ligament?
extremely strong and helps to limit eversion/pronation
what is the function of the lateral collateral ligament?
helps limit inversion/supination; weaker and more susceptible to injury
what 3 ligaments make up the lateral collateral ligament?
anterior talofibular ligament
calcaneofibular ligament
posterior talofibular ligament
what are the passive structure of the ankle?
MCL + LCL
what muscles support the MCL?
tibialis posterior, flexor hallucis longus, flexor digitorum longus
what muscles assist the LCL?
fibularis longus and brevis
Pair the osteo and arthrokinematics of the talocrural joint.
Dorsiflexion (think flex)- ant roll/post glide
Plantarflexion (think ext)-post roll/ant glide
what is the open pack position of the talocrural joint?
10 degrees plantarflexion with neutral inversion/eversion
what is the closed pack position of the talocrural joint?
maximum dorsiflexion
what are the ROM for dorsiflexion and plantarflexion respectively?
dorsiflexion: 20, plantarflexion: 50
what is the capsular pattern at the talocrural joint?
plantarflexion> dorsiflexion
list the 3 plantar arches
medial longitudinal
lateral longitudinal
transverse
what is the “keystone” of the medial longitudinal arch? lateral? Transverse?
Talus ;cuboid; intermediate cuneiform
what are the mobility functions of the foot arch?
dampen impact of weight bearing
dampen superimposed rotational motion
adapt to changes in supporting surfaces and terrains
what are the stability functions of the foot arch?
weight distribution; interchange between flexible and rigid lever
describe the windlass effect?
during propulsion of the foot, plantarflexors contract for heel rise, toe extension tenses the fascia inwardly to raise arch and create a rigid lever
What are the main motions at the subtalar joint in WBing?
triplanar motion>
Supination @ ST joint: ABD +dorsiflexion/
Pronation @ ST joint: ADD +plantarflexion
describe the subtalar joint (calcaneal positions) in nonweight-bearing supination and pronation.
Supination
calcaneus: inversion ADD /plantarflexion
Pronation:
calcaneus: eversion, ABD , dorsiflexion
describe the calcaneus motion at the subtalar joint in non-weight-bearing supination and pronation.
Supination
calcaneus: inversion/ADD/PF
Pronation
calcaneus: eversion/ABD/DF
what is the closed pack position of the subtalar joint?
full inversion
what is the open pack position of the subtalar joint?
mid inversion/eversion and mid PF/DF
what is the isolated ROM of the subtalar joint for eversion and inversion
5 degrees
What joints make up the transverse tarsal joint? What function does it serve?
talonavicular and calcaneocuboid; adds to sup/pro ROM, compensation @ forefoot for hindfoot position in closed chain (keeping foot on ground)
what is the open pack position of the transverse tarsal joint? closed pack?
midrange of sup/pro; supination
what are ROM for inversion and eversion?
inversion:35 degrees
Eversion: 15 degrees
what is the function of the tarsometatarsal joints?
regulating the position of the forefoot in relation to the weight bearing surface
Describe hallux limitus.
gradual and significant loss of ROM, pain and articular degeneration often after forceful hyperext (turf toe)
normal ambulation eq: 45-55 degrees
what are the 2 deformities outlined that may occur at the 1st MTP joint.
hallux limitus and hallux valgus
Describe hallux valgus.
progressive lateral deviation and can lead to dislocation
what is the function of the MTP joint?
WB: allow foot to rotate over toes through MTP ext when rising on toes or walking
Define pes planus. What effect does this foot posture have on the the overall function of the foot?
abnormal drop in medial longitudinal arch-often due to laxity in fascia; compromises supination and stability
Define pes cavus. What effect does this foot posture have on the overall function of the foot?
abnormally raised med longitudinal arch- often w/ excessive rearfoot inversion and forefoot eversion
What role does the posterior tibialis muscle play in the stance phase of ambulation
gradual controlled lowering of med arch, absorbs some of the loading impact; excessive/rapid pronation places high demands on it; supinates hindfoot for stable toe-off
