Gait kinematics of BN dancers with and without backpain
ABSTRACT: Bharatanatyam dance involves complex symmetric and asymmetric poses per-
formed in a maximal arc of motion which may result in kinematic changes reflected in a
common weight-bearing activity such as gait. Prevalence of low-back pain among dancers
has been reported to be 43.5%. The aim of this study was to investigate the kinematics of gait to understand musculoskeletal adaptations among Bharatanatyam dancers, and thus gain an understanding of the pathomechanics of spine pain. Seventeen active Bharatanatyam dancers with eight years of formal dance training formed Group A. Group B included dancers with chronic mechanical, nonradicular low-back pain, and Group C included healthy age-matched nondancers. Gait kinematics was recorded using 12 infrared cameras and 3D motion analysis. Participants were instructed to walk five times at a self-selected walking speed on a 10-mwalkway. Midgait data were processed in Vicon Nexus 2.4 to obtain peak joint angles of spine,pelvis, hip, knee, and ankle. Intergroup analysis was performed using the Kruskal-Wallis test.
Dancers with low-back pain exhibited 20% greater spine extension, 35% greater anterior pel-
vic tilt, and 30% lesser pelvic rotation compared to dancers without low-back pain. Kinematic
demands of typical dance postures resulted in increased spine extension, exaggerated anterior tilt, and obliquity of the pelvis. Implementation of a specific exercise program designed to neutralize excess deviation at the pelvis and spine may result in strength and conditioning effects to safeguard the lower back.
Key words: gait, dance, ballet, Bharatanatyam, low-back pain, kinematics