ABNORMALITIES OF THE THORACIC BELLOWS - STRESS-FRACTURES OF THE RIBS AND HIATAL-HERNIA

The thoracic bellows mechanism consists of the rib cage and the diaphr agm. The purpose of this study was to determine if nontriaumatically a cquired lesions of the bellows were secondary to underlying disease. A bnormalities of the bellows, specifically stress fractures of the ribs and hiatal hernia, were found in 21 dogs and cats with underlying car diopulmonary disease, neuromuscular disease, or metabolic disease. A c ase-control study of Bulldogs demonstrated that hiatal hernia was asso ciated with the more severe manifestations of brachycephalic syndrome. Stress fractures occurred mostly in females and in cats, and involved multiple ribs. Fractures were usually related to severe respiratory e ffort, but also occurred in association with metabolic disease. Hiatal hernia was also associated with severe respiratory effort, but may be exacerbated if a neuromuscular disorder affecting the diaphragm is pr esent. Abnormalities of the thoracic bellows, such as rib stress fract ures and hiatal hernia; may be signs of underlying disease, rather tha n being primary causes of disease.