Brachydactyly

Page most recently updated 7 September 2026

This page focuses on brachydactyly 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 brachydactyly 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 brachydactyly 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.

Short fingers

This patient has short fingers, in addition to short palms.

Image credit: National Human Genome Research Institute (NHGRI), Elements of Morphology.

Definition

  • Short fingers

Subjective: The middle finger is more than 2 SD below the mean for newborns 27–41 weeks EGA or below the 3rd centile for children from birth to 16 years of age AND the five digits retain their normal length proportions relative to each (i.e. it is not the case that the middle finger is the only shortened digit) OR fingers that appear disproportionately short compared to the hand.

Synonyms: Brachydactyly of the hand.

Note: As the determination of the proportionality of the other four digits is clearly subjective, the term must be regarded as subjective. The Bell classification of brachydactyly (summarized in Temtamy and McKusick 1969) is a complex assessment of hand patterning; that usage of the word brachydactyly is independent of the use here. When brachydactyly type x is used, this refers to the Bell classification patterns. When brachydactyly of the hand is used, it solely refers to reduced length of the specified digits. Short hand should not be used as it is a bundled definition of short fingers and short palm. If the distal phalanges are judged to be proportionately shortened, the additional term of short distal phalanges of the fingers should not be used. If the digit is short overall and the distal phalanx is disproportionately shorter than is the finger overall, then both terms should be used.

  • Short toes

Subjective: Digits that appear disproportionately short compared to the foot.

Synonyms: Brachydactyly of the foot.

Note: This finding must be distinguished from digits that are of increased girth but of normal length and that of a long mid- and hind foot with normal digit lengths. The affected digits should be specified as described in the introductory comments. Note that we designate brachydactyly as a synonym, but this use of the term is distinct from the use of the same word in Bell's classification.

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.