Fingernail Configuration

Abstract

BackgroundA number of conditions can alter a person's fingernail configuration. The ratio between fingernail width and length (W/L) is an important aesthetic criterion, and some underlying diseases can alter the size of the fingernail. Fingernail curvature can be altered by systemic disorders or disorders of the fingernail itself. Although the shape and curvature of the fingernail can provide diagnostic clues for various diseases, few studies have precisely characterized normal fingernail configuration.MethodsWe measured the W/L ratio of the fingernail, transverse fingernail curvature, hand length, hand breadth, and distal interphalangeal joint width in 300 volunteers with healthy fingernails. We also investigated whether age, sex, height, and handedness influenced the fingernail W/L ratio and transverse fingernail curvature.ResultsIn women, fingernail W/L ratios were similar across all five fingers, and were lower than those in men. The highest value of transverse fingernail curvature was found in the thumb, followed by the index, middle, ring, and little fingers. Handedness and aging influenced transverse fingernail curvature, but not the fingernail W/L ratio. Fingernails were flatter on the dominant hand than on the non-dominant hand. The radius of transverse fingernail curvature increased with age, indicating that fingernails tended to flatten with age.ConclusionsOur quantitative data on fingernail configuration can be used as a reference range for diagnosing various diseases and deformities of the fingernail, and for performing reconstructive or aesthetic fingernail surgery.

Aesthetic correction of short nail deformity in congenital brachydactyly Type D by distraction lengthening

“…Jung et al (2015) reported on the fingernail configuration in 300 volunteers with healthy fingernails. For aesthetic consideration, the ratio of nail length to width, which does not change with age and between different fingers, should be more than 1.0, while nails that are too long are also not considered to be aesthetically appealing (Jung et al, 2015;Rich, 1999). In our study, the target nail length of the affected thumb referred to that of the contralateral thumb if the BDD was unilateral, and referred to the corresponding normal baseline data if the BDD was bilateral.…”

Effect of fingernail length on the hand dexterity

“…First, subjects consisted of only healthy young adults. With increased age, the fingernails flatten and the contours are modified 11 ) , resulting in platonychias and koilonychias 24 ) . Fine motor hand movements also decline with aging 25 , 26 ) , and the effect of the fingernail length on such movements in the elderly is unknown.…”

“…In order to evaluate fingernail size, the length and width of the nail on the right thumb, index finger and middle finger of each subject were measured according to the method of Jung et al 11 ) . The length of the fingernail was defined as the greatest longitudinal distance from the groove at the junction of the eponychium and proximal nail fold to the tip of the finger.…”

Assessment of prenatal stress‐related cortisol exposure: focus on cortisol accumulation in hair and nails

“…The delayed appearance of the third peak in the zolpidem study as well as the major peaks reported in the fluoride studies is reasonably consistent with the length of the nail plate from root to tip combined with the average rate of nail growth. Measurement of fingernail length in a sample of healthy middle-aged men and women found an average length determined from all five fingers of 12.8 mm for men and 12.2 mm for women (Jung et al, 2015).…”

“…The delayed appearance of the third peak in the zolpidem study as well as the major peaks reported in the fluoride studies is reasonably consistent with the length of the nail plate from root to tip combined with the average rate of nail growth. Measurement of fingernail length in a sample of healthy middle‐aged men and women found an average length determined from all five fingers of 12.8 mm for men and 12.2 mm for women (Jung et al., 2015). With an average growth rate of 3.5 mm per month, we can see that it should take approximately 3.6–3.7 months in men and 3.5 months in women for newly formed nail plate tissue at the root to reach the end of the nail.…”