Reproducibility and Concurrent Validity of Manual Palpation with Rehabilitative Ultrasound Imaging for Assessing Deep Abdominal Muscle Activity: Analysis with Preferential Ratios

The abdominal drawing-in maneuver (ADIM) is a clinical tool used for identifying preferential activity of deep muscles. However, concurrent validity and reproducibility palpation during the ADIM has not been formally investigated. aims this study were (1) to assess intra- interrater reliability manual ADIM, (2) determine by calculating activation ratio cut-off as assessed with ultrasound imaging (RUSI). Thirty-two subjects (n = 16 patients nonspecific low back pain comparable healthy individuals) performed in supine hook-lying position. Two experienced assessors evaluated presence or absence contraction muscles on 2 different days. Intrarater (test-retest) calculated using Cohen’s kappa coefficients. Muscle thickness transverse abdominis (TrA), internal oblique (IO), external (EO) at rest also measured. TrA-Contraction Ratio (TrA-CR), TrA-Preferential Activation (TrA-PAR), Modified-TrA-PR (M-TrA-PAR) calculated. was determined correlation between ROC curve (operating characteristics curve), Youden index, sensitivity specificity. Intra- excellent (k: 0.82–1.00) good 0.71–1.00), respectively. Interrater muscle ranged from (ICC3,1 0.79–0.91). Manual TrA showed moderate correlations (r: 0.36–0.60). When evaluating diagnostic accuracy palpation, best predictive model (ROC value: 0.89; p < 0.001) correct obtained when M-TrA-PAR ≥0.08 (sensitivity: 0.95–1.00; specificity: 0.62). Good found both groups. supporting its use practice.