Hydatidosis or cyst hydatic disease is a cosmopolitan larval cestodosis caused principally by the <i>Echinococcus granulosus</i> tapeworm, the adult form of which parasitises the intestine of dogs. Hydatidosis generally affects large domestic herbivores; humans are dead-end hosts, infected through contact with herding dogs or through ingestion of food contaminated with canine excrement.

A pathologic fracture occurs when a bone breaks in an area that is weakened secondary to another disease process such as tumor, infection, and certain inherited bone disorders. A pathologic fracture can occur without a degree of trauma required to cause fracture in healthy bone.