Foot fractures and dislocations
So, a quick reminder of the bones of the foot pleaseeee….
There are a number of different parts of the foot that can be affected, first, consider the hindfoot. These include:
- Talus (commonly the neck although there are others such as the body)
- Subtalar dislocations
- Calcaneal fractures
In the forefoot the main fractures we must consider are:
- Metatarsal fractures
- Phalangeal fractures
Fractures of the Talus
The talus can be fractured by twisting injuries to the foot, violent dorsiflexion or an impact from below (i.e. calcaneal impaction). There are three types of talar fractures:
- Fractures of the body of the talus
- Fractures through the neck of the talus
- Osteochondral fractures
Talar neck fractures are divided based on the Hawkins classification, there are four types:
- Hawkins I - nondisplaced
- Hawkins II - subtalar dislocation
- Hawkins III - subtalar and tibiotalar dislocation
- Hawkins IV - subtalar, tibiotalar and talonavicular dislocation
Blood supply of the posterior tibial artery, anterior tibial artery and the perforating peroneal artery. These are of importance as avascular necrosis of the talar is a common complication, especially in Hawkins III and IV subtypes. Patients will often present with acute pain, an inability to walk or weight bear and considerable swelling, bruising and tenderness of the region.
In nondisplaced fractures a cast for 8-12 weeks can be used, in displaced fractures ORIF is indicated.
Fractures of the talus that are not the neck are rare, accounting for less than 1% of all fractures. The talar body accounts for 12% of talar fractures, the lateral process 10% and talar head fractures are the least common.
Fractures of the talar body are generally high energy traumas, with the foot in a supinated or pronounced position. Fractures of the lateral process of the talus are resulted from forced dorsiflexion, axial loading, and inversion with external rotation (found in snowboarders).
Fracture of calcaneus
The calcaneus is broken by a blow to the heel, mostly due to landing from a height. It is made of a cancellous bone and it is crushed at the moment of impact. Restoration of the anatomy is difficult.
Calcaneal fractures can be quite hard to spot, look for three things:
- Loss of Bohler’s angle (should be 25-40 degrees)
- Widening or disruption of the body on an axial view
- Separation of the ‘beak’ at the back of the bone