Mathematical evaluation of melatonin secretion in hypoxic ischemic encephalopathy.

Objectives: The aims of the study were to assess the kinematics of the lower limbs and pelvis during normal walking in professional ballet dancers and to investigate relationships between movements of segments of the lower limbs and pelvis.

Methods: Thirty one professional ballet dancers and twenty eight controls completed five walking trials at their preferred speed. Kinematic data in the basic anatomical planes for ankle, knee, and hip joints as well as for the pelvis were collected with an optoelectronic motion system.

Results: The female ballet dancers had in comparison with the controls significantly larger (p < 0.01) knee flexion in the swing phase and hip abduction in the preswing phase. Compared to the control group, the male ballet dancers had significantly larger dorsiflexion in the final stance and the total pelvic tilt range of motion. The number of significant correlations between kinematic parameters was higher in the female ballet dancers.

Conclusions: It can be concluded that specific movement techniques and compensatory strategies used in ballet dance can alter relationships between movements of segments of the lower limbs during normal walking. The relationships between movements in the joints of the lower limbs and pelvis are stronger in women.