Laterality in Body Coordination of Professional and Amateur Ballet Dancers While Performing a Single Pirouette with Pointe Shoes.

Abstract

Imbalances in muscle strength coordination owing to lateral preference may be a risk factor for injury in dancers. Postural control is essential for the basic turn in ballet (pirouette), owing to its lateral asymmetry. Since dance with pointe shoes demands greater range of motion, muscle strength, and balance control compared to dancing with flat shoes, pointe shoes may further add to the risk and cause an imbalance between the preferred and non-preferred legs during pirouette. In this study, we examined lateral differences in professional and experienced amateur ballet dancers during single pirouettes with pointe shoes to understand the multiple elements involved in lateral balance control in pirouettes. Eight female professionals and seven female amateur ballet dancers performed single pirouettes in pointe shoes on both the preferred and non-preferred sides. To understand the body coordination laterality in single pirouettes, statistical parametric mapping was performed for the trunk, hip, knee, ankle angle, and center of mass-center of pressure inclination angle timeframe data during the pirouette in three phases: turn with double-leg (Phase 1), single-leg (Phase 2), and finish turning with a single-leg (Phase 3). In addition, the hop-up time was calculated as the percentage when the foot is not in contact with the ground in Phases 2 and 3. There were no lateral differences in trunk and lower limb angles in either group. Professional dancers showed slightly more inclination towards the stance leg during left rotation at the beginning of the movement (Phase 1) with longer hop-up time in Phase 2, whereas amateur dancers tended to tilt forward during the left turn (Phases 1 and 2) with longer hop-up time in Phase 3. It is notable that the COP-COM inclination angle was adjusted by hop-up and it caused the lateral differences in both professional and amateur dancers during a single pirouette with pointe shoes. This study highlights elements to consider in laterality when monitoring pirouette performance with pointe shoes.