Digital Flexion Creases Case Study

Variability of Digital Flexion Creases in a Population group of West Bengal
Sangeeta Dey*1 and A.K. Kapoor2

1UGC-JRF, Department of Anthropology, University of Delhi, Delhi – 110007, India.
2Professor, Department of Anthropology, University of Delhi, Delhi – 110007, India.

*Corresponding author: Sangeeta Dey, UGC-JRF Research Scholar, Department of Anthropology, University of Delhi, Delhi – 110007, INDIA.

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Abstract: Digital flexion creases occurs on the volar surface of each finger at the level of interphalangeal joints. Three digital flexion creases are normally observed to exist on each finger of the hand except for the thumb because of its different anatomy; distal inter-phalangeal

They are also regarded as one of the external anatomical landmarks of the hand (Singh et al., 2002) in addition to palmar, thenar and wrist creases. According to Wurth (1937) and Aue-Hauser (1979), these creases are not formed primarily by embryonic flexion movements. They arise independent of fetal palm movement and are genetically determined. The presence of extra, displaced and missing digital flexion creases in individuals with normal joint anatomy and unusual digital creases variants in a number of syndromes indicates that genetic factors do probably play a role in digital creases formation (Stevens et al.,1988; Kamath et al., 2002). There are numerous studies focusing on different variants of flexion creases which are featured in a number of syndromes such as in Allagile syndrome (Kamath et al., 2002); partial deletions of chromosome 1q (Watson et al., 1986); Sickle cell anemia (Zizmor, 1973); Down’s syndrome (Penrose, 1931; Plato et al., 1973). However, few systematic studies are available on incidence patterns of digital flexion creases. This paucity of literature has prompted the author to conduct this preliminary work which aims at documenting the prevalence pattern of all the flexion creases

The occurrence of triple creases is minimal in the distal and proximal phalanx. Digit III is characterized by the highest number of extra creases at the proximal and metacarpo-phalangeal areas followed by digit IV then digit II and lastly digit V. Similar results were encountered among Japanese by Aue-Hauser et al (1980). A comparison of the creases patterns between right and left hand (Tables 1 and 2) reveals that there is no significant difference with respect to handedness. However mono and double creases tend to be more frequent in right than left hand while triple creases are encountered more in left as compare to right hand. The difference observed between the sexes was also statistically non-significant. Although, there is a uniform tendency that males have more low numbered creases than females however there is a predominance of high numbered and extra creases among females. Extra+ creases shows higher incidence among males.
The typical patterns of flexion creases in particular digits of the right hand can be best seen in Fig. 2 for males and Fig. 3 for females. However, the frequency distribution of flexion creases for the left hand was depicted in Fig. 4 for males and Fig. 5 for females. The incidence of extra + creases are extremely rare and generally restricted to the mid-phalangeal area of the digits. It has