Exploratory Agreement of 3D Body Surface Analysis with Expert Manual Assessment of Pelvic Malalignment in Patients with Non-Acute Low Back Pain: A Prospective Pilot Study with Linked Post-Hoc Analyses

Background/Objectives: We aimed to explore whether selected non-invasive three-dimensional (3D) body surface indicators differed between prospectively defined enrollment groups and, in linked post-hoc analyses, to identify candidate indicators associated with expert manual judgment.

Methods

At screening (visit 1), 88 participants underwent manual examination and pelvic X-ray assessment. Of these, 60 entered the prospective pilot study and underwent 3D body surface analysis at visit 2. The prespecified prospective comparison used the protocol-defined malalignment group (n = 30) and comparison group (n = 30). Final manual diagnosis served as an expert-judgment reference comparator. For post-hoc exploratory ROC analyses, the same 60 participants were reclassified according to final manual diagnosis alone as manual-positive (n = 40) or manual-negative (n = 20).