Coventional Radiograph Findings (lateral view left ankle): Flattening of Boehler's angle with multiple irregularities of the superior cortical outline of the calcaneous. These irregularities extend into the subtalar joint. Diffuse soft tissue swelling surrounding the ankle.

CT Findings(axial and coronal) Severly comminuted fracture of the calcaneous with disruption of both the middle and posterior facets of the subtalar joint. Subluxation of the middle facet medially and depression of the posterior facet.

Calcaneal fractures are often associated with thoracolumbar spinal injuries due to a common mechanism of injury (usually a fall from heights).

Boehler’s angle is commonly observed on lateral films and is formed by two intersecting lines. The first connects the superior margin of the anterior process and the posterior margin of the posterior articular facet. The second line connects the posterior margin of the posterior articular facet to the postero-superior margin of the calcaneal tuberosity. This angle should measure between 28 and 48 degress. Angles measuring less than 28 degrees are indiciative of a calcaneal fracture. Further evaluation of plain film findings by CT and will help to determine the severity of the injury and help guide the best treatment approach.

The Rowe classification system of calcaneal fractures is commonly used and is as follows. Type 1 fractures (~20%) involve the calcaneal tuborosity, the anterior process, or the sustintaculum tali. Type 2 (~5%) fractures are horizontal fractures of the calcaneal tuborosity. Type 3 (~20%) fractures are oblique fractures without extension to the subtalar joint. Type 4 (~25%) extend to the subtalar joint and type 5 (~30%) fractures are intraarticular with either depression of the posterior subtalar joint or have extensive comminution.

Manaster, B.J., Disler, David G., May, David A. Musculoskeletal imaging; The Requisites (2nd edition). 2002, Mosby, Inc.