Morphometric patterns among the 3D surface areas of human hand entheses

Area of Science:

• Paleoanthropology
• Biomechanics
• Anatomy

Background:

• Entheses, sites where tendons or ligaments attach to bone, are crucial for understanding biomechanical stress and functional adaptations.
• Previous methods for enthesis analysis lacked precision, hindering detailed morphological studies.

Observation:

• A novel, precise 3D methodology was developed and validated for quantifying hand enthesis areas.
• The study analyzed 17 entheses from the first, second, and fifth hand rays of 50 late-medieval individuals.
• Both raw and relative entheseal sizes were calculated, alongside correlations with bone and articular surface dimensions.

Findings:

• The new methodology demonstrated high precision with no significant error.
• Age did not significantly affect hand enthesis size, but significant sexual dimorphism was observed.
• Multivariate analysis revealed two distinct morphometric trends among hand entheses, potentially linked to prehensile grip function.

Implications:

• This precise 3D methodology provides a foundation for advanced enthesis morphology research.
• Biomechanical stress may influence relative enthesis size more than absolute size.
• Enthesis morphometric patterns offer insights into the evolution of hand function and prehensile grips.