There is an obvious comminuted intra-articular fracture of the calcaneus on the x-ray.

The Bohler’s angle is significantly reduced.

Bohler’s angle is an anatomic landmark on a lateral ankle x-ray. Normal value is between 20-40 degrees. An angle of less than 20 degrees indicates a compression fracture of the calcaneus.

The Bohler’s angle is formed by drawing 2 lines:

• A line from the highest point of the calcaneal tuberosity to the highest point of the posterior facet of the calcaneus.
• Another line from the highest point of the posterior facet to the top of the anterior process.

The intersection of the above two lines is Bohler’s angle.

Caveat- a normal Bohler’s angle does not exclude a calcaneal fracture.

Reference – Fundamentals of Diagnostic Radiology by Brant and Helms.