This particular soft-tissue parameter evaluates the position of PIII in relation to the coronary band. You can only get a true and accurate measurement if the barium paste wall maker extends up the hoof wall to the hair line of the coronary band. Without the marker, this area is not visable radiographically.
This soft-tissue zone should be monitored closely in acute laminitic cases. As the CE increases, notice that the sole depth decreases. The sole depth also decreases when the foot is trimmed. You must learn to tell the difference.
To measure the CE:
Locate the proximal (top) extent of the coronary band as marked by the white barium paste. Draw a line from PII past the outer edge of the hoof wall. This line should be parallel to the ground surface.
Locate the proximal (top) extent of the extensor process. Draw a line from this location past the outer edge of the hoof wall. This line also needs to be parallel to the ground surface.
Measure in millimeters the vertical distance between these two lines.
In this case, the CE measures 15mm.