Ankle and Foot Flashcards
what is the syndesmosis of the ankle
its a strong fibrous structure that joins the tibia and fibula together
its comprised of the anterior inferior tibiofibular ligaments (AITFL), the posterior inferior tibiofibular ligament (PITFL) and the intra-osseous membrane
what is the best definition of an ankle fracture
fracture of any malleolus (posterior, medial or lateral) with or without disruption to the syndesmosis
what are the different types of ankle fractures
isolated medial and isolated lateral malleolus fractures
bimalleolar fractures (medial + lateral)
trimalleolar fractures (medial + lateral + posterior)
what classification is used in ankle fractures and describe it - what type is the most unstable
Weber classification
Type A - below the level of syndesmosis
Type B - at the level of the syndesmosis
Type C - above the level of the syndesmosis
the more proximal the injury, the higher the chance of ankle instability, therefore type C weber fractures almost always need surgical fixation
what type of ankle fractures are the most unstable
weber type C ankle fractures (above the syndesmosis)
what is talar shift and why is it important
talar shift is when the space between the medial border of the talus bone and the lateral border of the medial malleolus has increased
its important because talar shift is an indicator of instability
what type of fractures would be suitable for conservative management
minimally displaced fractures
weber type A or Type B (with no talar shift) fractures
management of ankle fractures
conservative; immediate fracture reduction (to restore anatomical alignment), below-knee backslab
surgical; ORIF (displaced fractures, weber type C, open fractures, weber type B with talar shift)
what are the main complications following fractures and surgical fixation (for all fractures)
post-traumatic arthritis
mal-union
neurovascular injury
ankle sprains can be injuries to what ligaments and which is most common
anterior talofibular ligament
calcaneofibular ligament (more common)
what is the main mechanism of injury in a calcaneus fracture
fall from height - significant axial loading directly onto the bone
how are calcaneus fractures classified
intra-articular (more common) - involves articular surface of the subtalar joint (talus and calcaneus)
extra-articular - usually avulsion fractures by the achilles tendon
gold standard investigation into calcaneal fractures
x-ray initially to diagnose the fracture
but CT scan is gold standard in calcaneal fractures
management of calcaneal fractures
conservative; cast immobilisation (most calcaneal fractures are intra-articular and as such usually require surgical intervention)
surgical; closed reduction can be attempted in large but minimally displaced fractures, ORIF is most common
what is achilles tendonitis
inflammation of the achilles tendon
what is the role of the achilles tendon and what muscles does it unite
it unites the gastrocnemius, plantaris and the soleus
it inserts into the calcaneus and produces plantarflexion at the ankle
what is the mechanism of an achilles tendon tear
when a substantial sudden force is applied across the tendon
the precipitating event is often a sudden jump or a sudden change in direction when running
risk factors for achilles tendonitis or rupture
unfit individual who has a sudden increase in exercise frequency
poor footwear
male gender
obesity
clinical features of achilles tendonitis
gradual onset pain and stiffness in the posterior ankle, often worse on movement
tenderness over the tendon on palpation
clinical features of an achilles tendon rupture
sudden onset very severe pain in the posterior calf
audible popping sound
loss of power of ankle plantarflexion
investigations into achilles tendon rupture
clinical diagnosis
management of achilles tendonitis and rupture
tendonitis; ice, NSAIDs, rehab and physio
rupture; analgesia and immobilisation, ankle splinted in plaster in full equinus (plantarflexed) (nowadays usually a moonboot is used)
what is the common mechanism of injury of a talar fracture
typically high energy trauma in which the ankle is forced into dorsiflexion
this causes the talus to press against the tibia and fracture
what is the talus at high risk of when fractured
avascular necrosis
reliant on an extra-osseous blood supply which is highly susceptible to interruption in the context of fractures
