Anatomy of the Lower Leg, Ankle and Foot Flashcards
what is the most frequently injured major joint in the body?
ankle
what is the ankle essential for?
weight bearing
walking
what kind of joint is the ankle?
hinge
synovial
what bones are involved in the ankle joint?
distal part of tibia, fibular and upper part of talus
when is malleolar grip strongest?
dorsiflexion
when is the ankle joint unstable?
plantar flexion
name the main ankle ligaments
collateral ligaments
medial or deltoid ligament
lateral ligament
describe the deltoid ligament of the ankle
- Large, strong triangular band
- Three slips from medial malleolus to talus, calcaneus & navicular
- Stabilises the joint during eversion
describe the lateral ligament of the ankle
has 3 slips
weaker than medial
what ligament is commonly involved in ankle injuries?
lateral
what muscles dorsiflex the foot?
tibialis anterior
extensor digitorum longus
extensor hallucis longus
peroneus or fibular tertius
what muscles plantarflex the foot?
gastrocenemius
soleus
assisted by plantaris, tibalis posterior, flexor hallucis longus, flexor digitorum longus
what is a Pott fracture?
dislocation of the ankle
are ankle sprains inversion or eversion injury (usually)
inversion
what is a footballer’s ankle
repeated strain on the anterior capsule
what is tarsal tunnel syndrome?
tibial nerve compression deep to flexor retinacula
what is the main functions of the foot?
• Support the body in standing & progression • Lever it forwards in walking, running & jumping
at what joint(s) does foot inversion and eversion take place?
subtalar
transverse tarsal
what muscles are foot invertors?
tibialis anterior and posterior
what muscles are foot evertors?
peroneus longus and brevis
what are the functions of the foot arches?
- Bony arches
- Flexible & deform with each ground contact
- Acts as shock absorbers
- Distribute weight over the foot
- Act as springboards during walking, running & jumping
name the arches of the foot
longitutinal
medial longitudinal
transverse
what maintains the integrity of the foot arches?
• Shape of the united bones • Plantar aponeurosis • Long & short plantar ligaments • Spring ligament (calcaneonavicular) • Intrinsic muscles of foot
how many bones are there in the feet?
28 +
how many joints are there in the feet?
33
how many ligaments are there in the feet?
106
how many muscles are there in the feet?
20
name 3 accessory foot bones
os trigonum
accessory navicular
os peroneum
what may destabilise accessory bones of the foot
injury
sprain
where are tarsal coalitions common?
talocalcaneal
calcaneonavicular
what do tarsal coalitions cause?
stiff hindfeet
ankle arthritis is common after?
trauma
in a patient with ankle pain, no known trauma and < 50 what should you consider?
haemochromatosis
mean age of onset of ankle arthritis
46
mean age of onset of hip arthritis
51
what does cavovarus mean?
high arch of hindfoot
causes of cavovarus foot
neurological
club foot, idioapthic familial
post traumatic
pathogenesis of cavovarus foot
• Weakness of intrinsic muscles - clawing of toes
• ‘Plunger-effect’ by proximal phalanges - plantarflexion of MT’s – also
‘overaction’ of peroneus longus
• Weakness of peroneus brevis - hindfoot varus
• Weakness of tibialis anterior - equinus
• Overpull of tibialis posterior - adduction of forefoot
clinical manifestations of cavovarus foot
• Clawing of toes & plantarflexion of metatarsals - plantar callosities
and shoe problems
• Weakness of peroneus brevis - hindfoot varus - ankle instability
• Weakness of tibialis anterior – equinus - altered gait
• Overpull of tibialis posterior - adduction of forefoot - stress fractures
of lateral metatarsals
what questions must you ask when assessing cavovarus foot?
- Progressive?
- Family history?
- Muscle pain or weakness?
- Elevated creatinine kinase?
- Altered sensation?