Multi-segment spine range of motion in dancers with and without recent low back pain

Background:Altered spine kinematics are a common in people with LBP. This may be especially true for populations such as dancers, who are required to perform repetitive movements of the spine, although this remains unclear. Research question: Do dancers with recent LBP display altered spine kinematics compared to their asymptomatic counterparts? Methods: A cross-sectional study of multi-segment spine kinematics was performed. Forty-seven pre-professional and professional female dancers either with LBP in the past two months (n = 26) or no LBP in the past 12 months (n = 21) participated. Range of motion (ROM) during standing side bending, seated rotation, and walking gait were compared. Results: Female dancers with LBP displayed reduced upper lumbar transverse plane ROM in seated rotation (Effect Size (ES) = -0.61, 95% Confidence Interval (CI): -1.20, 0.02, p = 0.04), as well as reduced lower lumbar transverse plane ROM (ES= -0.65, 95% CI: -1.24, -0.06, p = 0.03) in gait. However, there was increased lower thoracic transverse plane ROM (ES = 0.62, 95% CI: 0.04, 1.21, p = 0.04) during gait. No differences in the frontal plane were observed. Significance: Altered transverse plane spine kinematics were evident in dancers with recent LBP for select segments and tasks. This may reflect a protective movement strategy. However, as the effect sizes of observed differences were moderate, and the total number of differences between groups was small, collectively, it seems only subtle differences in spine kinematics differentiate dancers with LBP to dancers without.