Reliability of Thoracic Spine Rotation Range-of-Motion Measurements in Healthy Adults

Abstract

The reliability of clinical techniques to quantify thoracic spine rotation range of motion (ROM) has not been evaluated. To determine the intratester and intertester reliability of 5 thoracic rotation measurement techniques. Descriptive laboratory study. University research laboratory. Forty-six healthy volunteers (age = 23.6 ± 4.3 years, height = 171.0 ± 9.6 cm, mass = 71.4 ± 16.7 kg). We tested 5 thoracic rotation ROM techniques over 2 days: seated rotation (bar in back and front), half-kneeling rotation (bar in back and front), and lumbar-locked rotation. On day 1, 2 examiners obtained 2 sets of measurements (sessions 1, 2) to determine the within-session intertester reliability and within-day intratester reliability. A single examiner obtained measurements on day 2 (session 3) to determine the intratester reliability between days. Each technique was performed 3 times per side, and averages were used for data analysis. Reliability was determined using intraclass correlation coefficients, standard error of measurement (SEM), and minimal detectable change (MDC). Differences between raters during session 1 were determined using paired t tests. Within-session intertester reliability estimates ranged from 0.85 to 0.94. Ranges for the SEM were 1.0° to 2.3° and for the MDC were 2.8° to 6.3°. No differences were seen between examiners during session 1 for seated rotation (bar in front, both sides), half-kneeling rotation (bar in front, left side), or the lumbar locked position (both sides) (all values of P > .05). Within-day intratester reliability estimates ranged from 0.86 to 0.95. Ranges for the SEM were 0.8° to 2.1° and for the MDC were 2.1 ° to 5.9°. Between-days intratester reliability estimates ranged from 0.84 to 0.91. Ranges for the SEM were 1.4° to 2.0° and for the MDC were 3.9° to 5.6°. All techniques had good reliability and low levels of measurement error. The seated rotation, bar in front, and lumbar-locked rotation tests may be used reliably when more than 1 examiner is obtaining measurements.