|Resource Paper: Turnout for Dancers - Hip Anatomy and Factors Affecting Turnout|
The paper is divided into several sections: (1) Bones of the hip joint, (2) Structure of the hip joint: the ball and socket, (3) Capsule and ligaments of the hip joint, (4) Muscles of the hip that create turnout, (5) Factors affecting turnout, and (6) Individual anatomical variations. It is important to begin with an understanding of the bones, so that the perception of turnout is structurally clear. Dancers can safely execute the skills requiring external rotation only if they have a sound knowledge of optimal individual skeletal and soft tissue range of motion capabilities . It is from ideas or images of movement tasks that the dancer can achieve the most efficient dynamic movement, and not by trying to coordinate and control individual muscle activation, or to achieve some ideal of perfection that is anatomically unrealistic. For those readers unfamiliar with the movement terminology used in this paper, there is an appendix of terms at the end.
Bones of the Hip Joint
Between the two innominate bones is the foundation for the pelvis, the sacrum (see Figure 3). The sacrum is a triangular-shaped bone that comprises five fused bones at the lower end of the spinal column. Lower still is the coccyx, four fused bones, often referred to as the tailbone. Dense ligaments hold the pelvis to the sacrum at junctions known as the sacroiliac joints, which are slightly moveable. Note in Figure 3 how the sacrum has a deep forward angulation relative to the final or 5th lumbar vertebra. This angle is almost 30 degrees on average.
The femur is more commonly known as the thigh bone (see Figure 4). Although all femurs share certain structural characteristics and landmarks, each person's anatomy is unique. The femur consists of the round head, the neck, the shaft and two condyles (lateral and medial) at the base of the femur. The femur is the longest bone in the body, and though it has movement in all three planes like the shoulder joint, it has much more limited range of motion.
This paper may be reproduced in its entirety for educational purposes, provided acknowledgement is given to the "International Association for Dance Medicine and Science."
Copyright © 2011 IADMS, Virginia Wilmerding, Ph.D., and Donna Krasnow, M.S.