Affects: Cats, Dogs
Brachycephaly (from Ancient Greek βραχύς, brakhús, meaning "short", and κεφαλή, kephalḗ, meaning "head") is the shape of a skull shorter than average in its species. It is perceived as a cosmetically desirable trait in some domesticated dog and cat breeds, notably the pug and Persian, and can be normal or abnormal in other animal species.
In humans, brachycephaly can appear both pathologically and non-pathologically as a result of normal human variation. It is particularly common in Mongolians and the Andamanese.
In anthropology, human populations have been characterized as either dolichocephalic (long-headed), mesocephalic (moderate-headed), or brachycephalic (short-headed). The usefulness of the cephalic index was questioned by Giuseppe Sergi, who argued that cranial morphology provided a better means to model racial ancestry.
Treatment: In humans, brachycephaly can be corrected with cranial remolding orthoses (helmets), which provide painless total contact over the prominent areas of the skull and leave voids over the flattened areas to provide a pathway for more symmetrical skull growth. Treatment generally takes 3–4 months, but varies depending on the infant's age and the severity of the cranial asymmetry.
However, studies by scientists in the Netherlands investigating helmet therapy on mild to moderate cases of brachycephaly have found there was no significant difference over time between infants treated with helmets and infants left untreated. All parents of infants treated with helmets confirmed negative side effects including skin irritation and sweating.
The study was criticised by the American Orthotic & Prosthetic Association in a letter to the New York Times. The letter noted that the study focused only on mild to moderate cases, saying that helmet treatment may still be useful for more severe cases. The letter also criticised the low participation rate (21%) of the randomized study, and noted that the incidence of fitting issues in the study, at 73%, "seems very high".