Brachycephaly

For brachycephalic animal breeds, see Cephalic index § Modern use in animal breeding, and Brachycephalic airway obstructive syndrome.

Brachycephaly
Other namesBrachyceplalic
Brachycephaly and dolichocephaly
SpecialtyMedical genetics

Brachycephaly (derived from the Ancient Greek βραχύς, 'short' and κεφαλή, '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.[1]

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.[2]

When pathological, it is known as flat head syndrome, and it results from premature fusion of the coronal sutures, or from external deformation. The coronal suture is the fibrous joint that unites the frontal bone with the two parietal bones of the skull. The parietal bones form the top and sides of the skull. This feature can also be a symptom of Down syndrome.

There are also cases of brachycephaly associated with plagiocephaly. Brachycephaly with plagiocephaly is positional and has become more prevalent since the "Back to Sleep" campaign. The Back to Sleep campaign began in 1994 as a way to educate parents about ways to reduce the risk for sudden infant death syndrome (SIDS). The campaign was named for its recommendation to place healthy babies on their backs to sleep. Placing babies on their backs to sleep reduces the risk for SIDS, also known as "cot death" or "crib death." This campaign has been successful in promoting infant back sleeping and other risk-reduction strategies to parents, family members, child care providers, health professionals, and all other caregivers of infants, at the cost of increasing the incidence of this deformation of the head.[3] It is considered a cosmetic problem.[4][5] Many pediatricians remain unaware of the issue and possible treatments. Treatments include regular prone repositioning of babies ("tummy time").[6]

  1. ^ "Cephalic index | skull shape, head shape, cranial index". Britannica. Retrieved 19 September 2023.
  2. ^ K. Killgrove (2005). Bioarchaeology in the Roman World (PDF) (M.A. thesis). UNC Chapel Hill. Archived from the original (PDF) on 28 March 2012.
  3. ^ John Persing; et al. (1 July 2003). "Prevention and Management of Positional Skull Deformities in Infants". Pediatrics. 112 (1): 199–202. doi:10.1542/peds.112.1.199. PMID 12837890.
  4. ^ "Plagiocephaly and brachycephaly (flat head syndrome)". NHS. 13 February 2012.
  5. ^ Matthew L. Speltz; et al. (15 February 2010). "Case-Control Study of Neurodevelopment in Deformational Plagiocephaly". Pediatrics. 125 (3): e537–e542. doi:10.1542/peds.2009-0052. PMC 3392083. PMID 20156894. Although DP is considered a purely aesthetic problem by many practitioners, several studies have challenged this view.
  6. ^ Di Rocco, Federico; Ble, Valeria; Beuriat, Pierre-Aurelien; Szathmari, Alexandru; Lohkamp, Laura Nanna; Mottolese, Carmine (30 April 2019). "Prevalence and severity of positional plagiocephaly in children and adolescents". Acta Neurochirurgica. 161 (6): 1095–1098. doi:10.1007/s00701-019-03924-2. PMID 31041593. S2CID 141503557.