Normative Values for Thumb Length in Central Indian Adult Population

Area of Science:

• Anthropometry
• Human anatomy
• Forensic science

Background:

• Establishing normative anthropometric data is crucial for various applications.
• Thumb length relative to the index finger can have implications in fields like ergonomics and forensics.
• Previous studies have not extensively detailed these specific measurements in Central Indian adults.

Purpose of the Study:

• To determine the relative thumb length compared to the index finger in Central Indian adults.
• To establish normative data for thumb-to-index finger length ratios.
• To investigate potential correlations with gender, laterality, and hand dominance.

Main Methods:

• A cross-sectional study involving 500 adult hands (316 males, 184 females) in Central India.
• Measurements included the thumb-proximal phalanx index and thumb-digital crease index.
• Data analysis focused on comparing relative thumb lengths across demographic groups.

Main Results:

• The thumb tip typically extends to 69% of the proximal phalanx length of the index finger.
• The thumb tip reaches 38% of the distance between the proximal and interphalangeal creases of the index finger.
• No statistically significant differences were found based on gender, laterality, or hand dominance.

Conclusions:

• The relative thumb length in Central Indian adults is consistently defined by specific ratios.
• Normal thumb length, in this context, is independent of gender, hand dominance, or which hand is used.
• These findings provide valuable anthropometric data for the Central Indian population.