Polyurethane inserts for comfort and injury prevention while dancing en pointe

Abstract

Pointe shoes have been made using the same rudimentary materials and methods for the past 200 years, and for this reason modern dancers lack access to more sophisticated equipment. Presented here is an insert that will last longer than a typical shoe, improve fit around the toes, and increase comfort. The insert was made from Simpact© 60A, a commercially available two-part polyurethane. Samples were tested cyclically at rates of 2, 4, and 6 mm/s in order to ensure that they would not wear out and become unusable. Inserts were also molded to the foot of a semi-professional dancer and tested to measure the force on the hallux. Using a polyurethane insert, this force was reduced to less than 10% of a ballerina's body weight. This is a dramatic improvement from an unmodified shoe, where over 60% of the dancer's weight can be on the hallux, and even a shoe with an epoxy modification, where the pressures are around 20% of the body weight. These inserts also lie completely inside the toe box of the pointe shoe, meaning they have no effect on the aesthetics of ballet. They increase comfort through improved fit and decreased force, allow ballerinas to maintain feel of the floor, and are predicted to extend the life of the pointe shoe.