Epidemiology and Classification
The incidence of talus fractures has increased in recent decades. Although previously comprising 0.85% to 1% of all fractures,[5,6] recent epidemiologic data suggest that talus fractures may constitute close to 2% of all fractures.[7,8] This may be related to motorcycle and motor vehicle collision-related foot trauma as patients increasingly survive more severe injuries.
Talus fractures are classified by anatomic region into head, neck, and body fractures. Neck fractures are subclassified by how many nearby articulations are disrupted based on observations in the historical case series of Hawkins and Canale. Type I fractures are nondisplaced, type II fractures exhibit subtalar subluxation or dislocation, type III fractures disrupt subtalar and tibiotalar joints, and type IV fractures disrupt subtalar, tibiotalar, and talonavicular joints. Vallier et al proposed dividing type II injuries into IIA, with subtalar subluxation, and IIB, with subtalar dislocation, because mere subluxation seems to beget a 0% rate of osteonecrosis and dislocation is associated with a 25% rate of osteonecrosis. The relative incidence of each Hawkins type in a 2013 systematic review was 22% type I, 43% type II, 31% type III, and 4% type IV.
Acute traumatic talar body fractures are differentiated from talar neck fractures on the basis of the inferior fracture line exiting into or posterior to the lateral process. Although no universal subclassification of talar body fractures exists, lateral and posterior process fractures are typically differentiated from those through the talar dome. Despite the greater historical attention talar neck fractures have received, talar body fractures have been found to be slightly more common in recent series,[10,11] constituting 53% to 60% of all talus fractures.
J Am Acad Orthop Surg. 2020;28(20):e878-e887. © 2020 American Academy of Orthopaedic Surgeons