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Updated: Jun 22, 2026

Automated Joint Space Detection Improves Bone Segmentation Accuracy
Published on: November 28, 2025
Joint orientation and function in great ape and human proximal pedal phalanges
Nicole L Griffin1, Brian G Richmond
1Center for the Advanced Study of Hominid Paleobiology, George Washington University, Washington, DC 20052, USA.
Dorsal canting of the proximal phalanx indicates differences in human and ape forefoot function. Unshod human feet provide the best comparison for fossil hominins, revealing insights into bipedality.
Area of Science:
- Paleoanthropology
- Biomechanics
- Primate Anatomy
Background:
- Dorsal canting of the proximal phalanx is a key indicator of human-like metatarsophalangeal joint function and bipedality.
- Previous research has established differences in proximal phalangeal joint orientation between humans and great apes.
Purpose of the Study:
- To investigate finer-scale differences in forefoot function using dorsal canting.
- To determine if dorsal canting reflects sexual dimorphism in locomotor behavior.
- To assess the influence of habitual shoe wear on dorsal canting in humans.
- To compare proximal joint morphology between different rays in Pan and humans.
Main Methods:
- Measurement of dorsal canting of the proximal phalanx base.
- Comparative analysis of proximal phalangeal joint orientation in humans and Pan.
- Investigation of sexual dimorphism in dorsal canting within gorilla and chimpanzee species.
- Comparison of dorsal canting in habitually shod versus minimally shod humans.
Main Results:
- Humans exhibit significantly more dorsally canted proximal phalanges than great apes, with overlapping ranges.
- Male gorillas show more dorsally canted second proximal phalanges than females; the opposite is true for Pan troglodytes.
- Pan display more dorsal canting in the first proximal phalanx compared to the second, while humans show the reverse pattern.
- Minimally shod humans have more dorsally canted second proximal phalanges than habitually shod humans.
Conclusions:
- Phalangeal joint orientation reflects interspecific differences in metatarsophalangeal joint function.
- Unshod human foot morphology serves as a more appropriate comparative sample for early hominin analyses.
- Dorsal canting measurement has limitations in detecting certain intraspecific functional variations but is valuable for understanding broader patterns of bipedality.
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