This study demonstrated that, in
a standing posture, increasing the
degree of anterior pelvic tilt increased
the angle of lumbar lordosis
and increasing the degree of posterior
pelvic tilt decreased the angle of
lumbar lordosis. This is in agreement
with the observations of Day et al (4),
where the depth of lumbar lordosis
was shown to deepen during a voluntary
maximal standing anterior pelvic
tilt and to become more shallow during
a posterior pelvic tilt. The results
of Day et a1 are not directly comparable
with the present study, since they
defined the magnitude of the lumbar
lordosis as the depth of the curve at
its apex, rather than as an angular
change in the skin surface. The
present study has quantified the relationship
between pelvic tilt and lumtant in teaching subjects to maintain
a particular pelvic posture, such as
performing an anterior pelvic tilt
during lifting, thus increasing lumbar
lordosis, which decreases intradiscal
pressure (1 ) . The main limitation of the
present study is that it was performed
on a sample of college students who
were devoid of low back troubles.
The generalizability of the results is
therefore limited. This population
was chosen because it was felt that
the relationships first needed to be
investigated in normal individuals
before analyzing the more complex
relationships that may exist in individuals
with low back dysfunction.