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 handComments:
This is an acknowledged bundled term as the definition in most anthropometric sources assumes that the other fingers are all as relatively short as is the middle finger. 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 ) 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 are the finger overall, then both terms should be used.