Rare cranial osteopathy in a Northern Bottlenose Whale (Hyperoodon ampullatus) stranded in Rhode Island, Northwest Atlantic, in the 19th century

Few reports exist on the pathologies of the northern bottlenose whale (Hyperoodon ampullatus) and other Ziphiidae. We here describe a large bony outgrowth (exostosis) in the right pterygoid bone of an adult female H. ampullatus, ANSP 3004, that stranded on the US Atlantic coast in 1867. Images of the skull and 14 cranial measurements were examined and compared with two ‘normal’ adult female H. ampullatus specimens. The form, structure, and width of the right pterygoid were found to be abnormal. Its distal extremity was curved in a labial direction, while its proximal extremity was deformed by a large, bulbous bony outgrowth that partially obstructed the right nasal passage. Lytic lesions in the posterior end of the exostosis exposed deep resorption lacunae. The left pterygoid was thin and laterally displaced. No diagnosis was possible for lack of histological examination but the bony outgrowth was suggestive of an osteoma, a benign bone tumor commonly seen on the jaws and nasal sinuses of horses, bovines and sheep. The partial nasal passage obstruction may hypothetically have affected respiration to some degree, but since the female was lactating, general fitness appeared sufficient.