Reliability of Ultrasonography in Measuring Deep Abdominal and Lumbar Multifidus Muscle Dimensions in Patients with Unilateral Lumbar Disc Herniation

Introduction: The purpose of this study was to assess the within-day and between-day reliability of abdominal and lumbar multifidus muscle size in patients with unilateral lumbar disc herniation (LDH) using ultrasonography (US). Materials and methods: In this study, 15 patients with unilateral LDH (20-60 years old) were recruited. To assess within-day and between-day reliability, three images were taken with one hour and one week intervals respectively. The images were taken at rest and during contraction. Results: The within-day and between-day reliability of abdominal muscle thickness measurements using US in patients with unilateral lumbar disc herniation (LDH) in both rest and contraction state was found to be high with ICC=0.87 for within and ICC=0.75 for between-day rates of transverse abdominis (TrA) muscles at rest and ICC=0.78 and 0.75, respectively, in contraction state. For internal oblique muscles, ICC=0.70 at rest and 0.79 in contraction state and ICC=0.73 at rest and 0.77 in contraction state were found for within-day and between-day, respectively. Within-day and between-day reliability at rest with ICC=0.76 and 0.76 and in contraction state with ICC=0.75 and 0.74 were demonstrated for the external oblique muscle. Within-day and between-day reliability rates at rest with ICC=0.88 and 0.84, respectively, and in contraction state with ICC=0.84 and 0.80, respectively were demonstrated for the lumbar multifidus muscle. Conclusion: The results of the present study suggest that US is a reliable method for evaluating the thickness of the abdominal and lumbar multifidus muscles. However, further research is recommended to support the findings of the present study.Keywords: Ultrasonography, disc herniation, abdominal muscles, lumbar multifidus muscle, reliabilit