What is the appropriate central ray location for a plantodorsal axial calcaneus radiograph?

For a plantodorsal axial calcaneus radiograph, the correct central ray location is at the base of the third metatarsal. This positioning is essential to accurately visualize the calcaneus, which is also known as the heel bone. The central ray entering at the base of the third metatarsal allows for optimal projection, ensuring that the anatomy of the calcaneus is centered and clearly depicted on the image. This approach minimizes distortion and provides a clear view of the subtalar joint and the surrounding structures, which is beneficial for diagnostic purposes.

Positioning the central ray at other locations, such as the first, second, or the base of the third metatarsal, would not center the calcaneus appropriately, thus compromising the quality of the radiograph. Additionally, locating the central ray midway between the heel and the ankle joint would similarly lead to a misrepresentation of crucial anatomical structures, potentially obscuring necessary details for evaluation.