Neck webbing
Page most recently updated 7 September 2026
This page focuses on neck webbing as a morphologic feature of conditions that may also be associated with psychiatric manifestations, such as psychosis, mania, autism spectrum disorder, ADHD, OCD, and self-injurious behaviours. The page begins with a clinical definition of neck webbing based on the standardized Elements of Morphology terminology, together with visual examples from the same source. This is followed by a list of conditions in which neck webbing has been described in association with psychiatric manifestations.
Of note, to optimize clinical utility, the list does not include conditions associated with intellectual disability in the absence of other psychiatric features.
Each condition listed below is linked to a dedicated page within this resource. These pages describe the psychiatric manifestations associated with each condition, as well as other morphologic and broader clinical features, allowing the differential diagnosis to be considered from multiple perspectives.
Neck webbing
Image credit: National Human Genome Research Institute (NHGRI), Elements of Morphology.
Definition
Subjective: A paravertically oriented fold of skin on the posterolateral aspect of the neck, usually extending from the mastoid region of the skull to the acromion, and best appreciated in frontal or posterior view.
Comments: This feature is often accompanied by a low posterior hairline, but this should be considered a separate morphologic feature.
Synonyms: Pterygium colli.
Conditions with potential psychiatric associations
Selected references and further reading — Morphologic lens
Allanson JE, Biesecker LG, Carey JC, Hennekam RCM. Elements of morphology: introduction. Am J Med Genet A. 2009;149A(1):2-5.
Hennekam RCM, Biesecker LG, Allanson JE, Hall JG, Opitz JM, Temple IK, Carey JC; Elements of Morphology Consortium. Elements of morphology: general terms for congenital anomalies. Am J Med Genet A. 2013;161A(11):2726-2733.
Jones KL, Jones MC, del Campo M. Smith's recognizable patterns of human malformation. 8th ed. Philadelphia: Elsevier; 2021.
Reardon W. The bedside dysmorphologist: a guide to identifying and assessing congenital malformations. 2nd ed. Oxford: Oxford University Press; 2016.