Calcaneous Anatomy / Xrays

Calcaneous Superior View

1. Anterior facet
2. Middle facet
3. Posterior facet
4. Sustentaculum tali
5. Tuberosity
6. Lateral wall

Calcaneous Anterior View

1. Posterior facet
2. Middle facet
3. Sustentaculum tali
4. Cuboid articulation

Calcaneous Posterior View

1. Sustentaculum tali
2. Groove for FHL
3. Medial process of the calcaneous
4. Tuberosity

Calcaneous Lateral View

1. Tuberosity
2. Posterior facet
3. Sustentaculum tali
4. Anterior process
5. Peroneal troclea

• Measured on lateral xray
• Usually between 20°-40°.
• Formed by lines drawn from the highest point of the anterior process of the calcaneous to the highest point of the posterior facet and a line drawn tangential to the superior edge of the tuberosity. 
• Decrease indicates posterior facet has collapsed.

• Measured on lateral xray
• Seen directly inferior to the lateral process of the talus, formed by lines along lateral border of posterior facet and anteriorly to the beak of the calcaneous.
• Usually between 95° and 105°.

Calcaneous Primary Fracture Line

1. Anteromedial fragement
   -variable portions of the posterior facet, anterior process, middle and anterior facets, sustentaculum tali
   -"Constant" fragment
2. Primary fracture line
3. Posterolateral fragment
   -tuberosity and lateral wall with variable portions of the psterior facet