The effects of "raked" stages on standing posture in dancers

Professional dancers performing on "raked" (inclined) stages sustain more injuries than dancers who perform on flat stages. However, the effects of raked stages on standing posture have not been examined. Eight professional dancers stood for four seconds on flat and inclined surfaces while trunk and lower extremity angle data were collected in a controlled laboratory environment. Twelve separate ANOVA procedures were used to evaluate the effect of floor (flat vs. inclined) on kinematic variables. Dancers stood with 3.3 degrees less dorsiflexion in the posterior incline and 4.7 degrees more dorsiflexion in the anterior incline (p < .001). They also stood with increased pronation: 2.1 degrees in the posterior (p = .009), 4.10 degrees in the anterior (p = .006), and 5.20 degrees in the lateral condition (p < .001). With regard to hip abduction, the subjects demonstrated 2.90 degrees more in the medial condition and 2.70 degrees less in the lateral condition (p = .001). External hip rotation was 3.30 degrees higher for the medial (p = .027) and 5.77 degree slower in the lateral condition (p = .002). Thus, the findings of the present study demonstrate that there are significant hip and ankle angle joint differences between standing on flat and inclined surfaces. Future research should investigate the relationship of these biomechanical differences to overuse injuries.