The Pelvic Girdle and Hip Joint 179125° to 130° in the adult and further decreases to
about 120° in old age (Levangie and Norkin, 2001;
Mercier, 1995). The angle of inclination has an
important influence on the mobility and stability of
the femur, as well as knee and lower leg alignment.
Normally, this inclination helps angle the femur
inward so that the center of the knee joint is close to
being vertically aligned with the head of the femur
and center of motion of the hip joint.
Coxa Vara
When the angle of inclination is abnormally
decreased, the condition is called coxa vara (coxa, hip
- L. varus, bent inward) as seen in figure 4.16A. This
condition decreases the load on the femoral head
but increases the load on the neck and increases the
risk of fracture of the neck of the femur (Hamill and
Knutzen, 1995). Regarding mobility, a decreased
angle can decrease the range of hip abduction
but increase the effectiveness of the hip abductors
(greater lever arm). Regarding lower leg alignment,
with a decreased angle of inclination there is a
tendency for the shaft of the femur to slope more
inward than normal and to produce a knock-kneed
alignment termed genu valgum (see chapter 5), in
which the knees are medial to the feet during stand-
ing in anatomical position.Coxa Valga
When the angle of inclination is abnormally
increased, the condition is called coxa valga (coxa,
hip + L. valga, turned outward) as seen in figure
4.16C. This condition increases the load on the
femoral head but decreases the load on the neck of
the femur. Regarding mobility, an increased angle
can increase the range available in hip abduction
but reduce the effectiveness of the hip abductors
(decreased lever arm). Regarding lower leg alignment,Pelvic Alignment: Anterior Pelvic Tilt,
Posterior Pelvic Tilt, and NeutralUse figure 4.15 for reference and the procedure described next to learn to identify an anterior pelvic
tilt, posterior pelvic tilt, and a neutral pelvis.- Stand in parallel first position with your side to a mirror, and place your right index finger on
your right ASIS and your left index finger on your left ASIS.
a. Tilt the top of the pelvis forward to create an anterior pelvic tilt, and note in the mirror that the
ASIS are in front of the pubic symphysis.
b. Tilt the top of the pelvis backward to create a posterior pelvic tilt, and note in the mirror that
the ASIS are behind the pubic symphysis.
c. Tilt the top of the pelvis in the necessary direction to create a neutral pelvis by lining up the
ASIS directly above the pubic symphysis, in the same vertical plane. - Stand in a parallel first position, and note the alignment of your pelvis. Make any necessary
corrections to effect a neutral pelvic alignment. - Perform a demi-plié and relevé in parallel and turned-out first positions. Note the alignment of
your pelvis throughout the movement and make any necessary adjustments to maintain neutral
pelvic alignment. Are there any differences in your pelvic alignment between standing, demi-plié,
and relevé in parallel or turned-out positions? - Repeat steps 2 and 3 with a partner and, if necessary, help each other to make the neces-
sary adjustments to maintain a neutral pelvic alignment. - Now, note if asymmetries exist in relative positioning of your ASIS in the transverse and frontal
planes. Place your fingertips on each ASIS, and look at the pelvis from the front. With neutral
alignment, the ASIS should be in the same transverse plane; that is, they should appear at the
same level or height versus have one lower than the other. They should also be in the same frontal
plane versus have one rotated in front of the other.