17. Calcaneus, fractures. The Bohler angle. A line is drawn from the most posterior superior aspect of calcaneus to the midpoint, the posterior subtalar joint. This line is intersected at the midpoint by a second line from the most anterior superior aspect of the calcaneus. The Bohler angle is normally 20-40°; if the angle is reduced, there is a calcaneal fracture. However, a normal angle does not exclude a calcaneal fracture