Dance Anatomy & Kinesiology

The Pelvic Girdle and Hip Joint 181

internal rotation of the femur, which can be respon-

sible for in-toeing, or the tendency to have the toes

face inward, as seen in figure 4.18B. When femoral

anteversion is excessive, more of the anterior head

of the femur becomes uncovered, and internal rota-

tion of the femur is required to better position the

head of the femur in the acetabulum (Hamill and

Knutzen, 1995). Increased femoral anteversion is also

associated with decreased external rotation, prob-

ably due to earlier contact between the neck of the

femur and the lateral edge of the acetabulum. Due

to the restricted external rotation and the tendency

for in-toeing, excessive femoral anteversion is con-

sidered undesirable for the dancer in professional

training, particularly in classical ballet. Femoral

anteversion can also negatively impact alignment

above and below the hip and is commonly associ-

ated with lumbar lordosis, an increased Q angle,

and patellar problems (discussed in chapter 5), as

well as excessive pronation of the foot (discussed

in chapter 6).

Femoral Retroversion

A decrease in the angle of femoral torsion, versus an

increase, is termed femoral retroversion (turning

backward). Femoral retroversion results in greater

hip external rotation, which can lead to out-toeing,

or the tendency for the feet to face markedly out-

ward as seen in figure 4.18C. Due to the associated

increased hip external rotation or turnout, femoral

retroversion is considered desirable for dancers in

dance forms emphasizing turnout.

Pelvic and Hip Mechanics

Due to the very limited motion allowed at the pubic

symphysis and sacroiliac joints, the pelvic girdle

primarily acts as a unit, with movement of the pelvis

tending to produce movement in the lumbar spine

and at both hip joints. In some conditions, linked

movements of the pelvis, lumbar spine, and hip

joints are encouraged, while in other cases there is

an attempt to limit the associated movements in favor

of stabilization of one of the segments.

Linked Movements

of the Pelvis, Femur, and Lumbar Spine

Movement of the pelvis occurs relative to the spine,

primarily at the lumbosacral joint, and relative to

the femur at the hip joint. Movements can be initi-

ated from the spine, pelvis, or femur and will tend

to produce predictable secondary movements in the

other two segments as well. The linked movements

that tend to occur will be influenced by whether

both ends of the chain are closed, the head is free

to move, or the leg/foot is free to move.

Closed-Chain Pelvic Movements

While the terms closed and open kinematic chain

are more commonly used for limbs, the concept can

also be applied to the pelvis. During erect standing

the distal part of the chain becomes fixed (foot).

While not structurally fixed, the proximal end of

FIGURE 4.18 Angle of femoral torsion and potential influence on lower leg alignment (left hip, superior view).
(A) Normal, (B) femoral anteversion and associated in-toeing, (C) femoral retroversion and associated out-toeing.

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