Automated resolution independent method for comparing in vivo and dry trabecular bone

Area of Science:

• Paleoanthropology
• Biomechanics
• Medical Imaging

Background:

• Trabecular bone morphology variation is linked to habitual behavior.
• In vivo investigation is challenging due to high-resolution imaging radiation requirements.
• Functional interpretations of trabecular morphology are currently inferential.

Purpose of the Study:

• Introduce a novel method to link low- and high-resolution CT data from dry and fresh bone.
• Enable in vivo study of bone functional adaptation.
• Facilitate comparison with the fossil and archaeological record.

Main Methods:

• Examined 51 human dry bone distal tibiae and two pig tibiae with soft tissues.
• Compared low-resolution peripheral quantitative computed tomography (pQCT) and high-resolution micro CT (μCT) parameters.
• Utilized a novel Bone Ratio Predictor (BRP) method for data analysis.

Main Results:

• The Bone Ratio Predictor (BRP) accurately predicts bone area/total area (BA/TA) (R² = .97) and eliminates geographic clustering.
• BRP accurately estimates BA/TA in pigs with soft tissues (R² = .98) without phantom calibration.
• Regression slopes differed significantly between geographical subsamples without BRP, likely due to diagenesis.

Conclusions:

• BRP enables automated comparison of diverse bone imaging data (pQCT, μCT) from various sources (archaeological, wet specimens).
• The method allows in vivo low-resolution data to be compared with the fossil and archaeological record.
• This approach significantly enhances behavioral inferences derived from trabecular bone microstructure.