The Pelvic Girdle and Hip Joint 183
can produce the desired arch in the low back from
the anterior tilt produced by greater contraction
of the hip flexors versus contraction of the spinal
extensors located in the lumbar region.
Lumbar-Pelvic Rhythm
In contrast to the condition just described, when
the distal end of the chain is fixed (feet) by standing
but the proximal end of the chain (head) is free
to move, linking between the spine, pelvis, and hip
is termed the lumbar-pelvic rhythm. One impor-
tant example of the lumbar-pelvic rhythm occurs
during bending forward from a standing position
and then returning to an upright position (Cail-
let, 1996). Only about 50° to 70° of spinal flexion
(Soderberg, 1986) is possible in most individuals
(figure 4.20B), and then additional movement is
due to anterior tilting of the pelvis and flexion at the
hip joint (figure 4.20, C and D). When this flexion
is complete, support of the body weight relies on
passive support (flexion relaxation phenomenon).
Return from this fully flexed position should reverse
this process used with forward flexion, beginning
with extension of the hip joint and posterior tilting
of the pelvis, followed by extension of the spine.
This return from forward flexion should be a well-
coordinated movement; and disruption of this
lumbar-pelvic rhythm, such as extending the back
too soon or returning in an asymmetrical manner,
can increase risk for low back injury.
This movement is commonly used in modern and
jazz classes (“roll-downs”); and cues frequently used
by teachers to bend the knees slightly and bring the
pelvis under, before stacking the spine on the pelvis,
can be helpful for encouraging this desired lumbar-
pelvic rhythm and reducing low back stress. With
forward flexion from a standing position, the ischial
tuberosities move backward relative to the hip axis as
seen in figure 4.20, A-D; so the hamstrings can pull the
ischial tuberosities downward and forward, while the
gluteus maximus draws the pelvis back to help return
the pelvis to a vertical/neutral position. Starting this
return motion with the pelvis delays extension of the
spine until the trunk is closer, such that the moment
FIGURE 4.20 Lumbar-pelvic rhythm. (A) Neutral pelvis and spine, (B) spinal flexion, (C) anterior pelvic tilt and hip flexion,
(D) forward hang.
A B D C
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