Sacral Anatomical Orientation in the Lebanese Population

Area of Science:

• Orthopedics and Spine Surgery
• Radiology and Medical Imaging
• Biomechanical Engineering

Background:

• Pelvic incidence (PI) is the gold standard for spinopelvic anatomy measurement.
• A reliable method for sacral anatomic orientation (SAO) independent of posture is needed.
• Previous research established an association between PI and SAO in a limited sample.

Purpose of the Study:

• To apply and verify the association between SAO and PI in a Lebanese population.
• To establish SAO as a reliable, posture-independent measurement in spinopelvic assessment.

Main Methods:

• Study conducted on 200 adult individuals using CT 3D imaging (volume-rendering).
• Methods for measuring SAO and PI on living subjects were employed.
• Intraclass correlation tested reliability; regression analysis evaluated SAO-PI association.

Main Results:

• Mean SAO was 52.65° (SD=8.16°) and mean PI was 59.08° (SD=12.53°).
• A significant negative correlation was found between SAO and PI (r=-0.296, P<0.0001).
• A predictive equation for SAO based on PI was established: SAO = (-0.193 × PI) + 64.057.

Conclusions:

• SAO is a reliable, posture-independent measurement valuable in spinopelvic assessment.
• SAO, alongside PI, aids in defining spinal sagittal shape.
• Understanding the SAO-PI association is crucial for evaluating spinal diseases.