Benjamin Hidalgo, PE, PT, DO, MT, Maxime Gilliaux, PT, William Poncin, PT and Christine Detrembleur, PT, PhD

OBJECTIVE: To develop a standardized, reliable, valid spine model of active trunk movements that accurately discriminates kinematic patterns of patients with chronic non-specific low back pain from those of healthy subjects.

DESIGN: Comparative cohort study.

SUBJECTS: Healthy subjects (n = 25) and patients with chronic non-specific low back pain (n = 25) aged 30–65 years.

METHODS: Subjects performed 7 trunk movements from a seated position at non-imposed speed during 2 sessions. Nine markers on bony landmarks measured range of motion and speed of 5 spinal segments, recorded by 8 optoelectronic cameras.

RESULTS: Both groups showed good–excellent reliability in all movements for range of motion and speed of all spinal segments (intraclass correlation (ICC), 0.70–0.96; standard error of measurement, expressed as a percentage, 19.4–3.3%). The minimal detectable change in the patient group was 16.7–53.7%. Range of motion and speed in all spinal segments for trunk flexion, rotation, and flexion with rotation differed significantly between groups (p < 0.001), with large/very large effect sizes (Cohen’s d = 1.2–2). Binary logistic regression yielded sensitivities/specificities of 92%/84% for range of motion and 92%/80% for speed. CONCLUSION: Kinematic variables are valid, reliable measures and can be used clinically to diagnose chronic non-specific low back pain, manage treatment, and as quantitative outcome measures for clinical trial interventions. Key words: kinematics, low back pain, diagnosis, movement, reliability, validity, spine. J Rehabil Med 2012; 00: 00–00 Correspondence address: Hidalgo Benjamin, Université Catholique de Louvain, Institute of Neuroscience, Avenue Mounier, 53 – B1.53.04, BE-1200 Brussels, Belgium. E-mail: benjamin.hidalgo@uclouvain.be Submitted August 24, 2011; accepted April 2, 2012 Full Text Article