STRUCTURE OF SKELETAL BONE: NORMAL VS. ROTTEN

The first step in becoming good at CSI-style analysis is to learn not to overinterpret evidence—in short, not to make mountains out of molehills. The analyst must realize the difference between the normal appearance of bone (below) versus injuries, pathologies or developmental anomalies, and must also be able to distinguish pre-mortem from postmortem damage. The images at right are four views of Ethan Allen’s left carpal bones (the small bones that form the “knee” joint). The smooth, pinkish material visible between some of the bones is jeweler’s wax used to hold them together without harming them.

Especially in the front and rear views, the bones appear rough, with a finely bubbly texture (yellow arrows). This is not an abnormality but the normal appearance of cancellous bone, visible because 11 years spent buried in earth eroded away the outer, lamellar covering over parts of the shafts of the bones, exposing the cancellous bone within. By contrast, surfaces of the carpal bones in top and bottom views look smooth and shiny. They represent articular facets that were thick and hard enough to withstand burial conditions. Thus, the joints comprising Ethan Allen’s carpus—like almost the whole of his skeleton—show almost zero pathology, proving him to have been exactly as contemporary reports made him out to be: one of the soundest stallions ever to be bred in America.