Dr. Siff:

You make a good point about treating posture.  Unfortunately, there are
incidences when people assume poor posture due to poor muscular strength and
endurance.  This can be seen in several people who sit or stand slouched.
These people are positioning themselves in postures that require little
muscular control resting on facet joints or ligaments.  When you get these
people to move out of those positions there pain goes away often.  But, the
problem is they get sore muscles due to having to control this different
posture and they can't tell the difference often.  It's like new muscle
activity soreness.

This isn't only seen in the spine, it's also seen in the knee and other
joints.  For example the person who is in genu recurvatum or valgus may
develop knee pain.  A great example I remember from a lecture by Shirley
Sarhman is when a patient said as she lunged "it hurts my knee when I do
this", she said "don't do it then!"  Then she showed the patient how to move
correctly, gave her exercises to develop the muscles to do this.

My point is there has to be more than just strengthening muscles and
improving endurance to rid people of musculoskeletal problems.  They need
proper body mechanics too, and this relates to postural control, leg length
discrepancies, etc..  Just to say that one thing isn't associated with
another doesn't mean you have to throw it out.  I think the reason posture
doesn't show up as significant in these studies is because posture is
represented in a bell shape distribution there and atleast 80 percent of
people have back pain.  So statistically it will never show up that
increased lordosis is significant to the incidence of LBP.

Patrick Zerr
www.apluspt.com
The easiest way to prepare for the National PT Exam!
www.summitpt.com
Summit Physical Therapy; Tempe, Arizona


----- Original Message -----
From: <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, September 27, 2002 12:27 PM
Subject: Mechanical Factors and LBP?


This very recent study from Iran (note, researchers outside Canada and
Australia are also producing some interesting findings in the field of LBP)
confirms what other studies are revealing about all those postural and
mechanical beliefs about low back pain and its treatment.

This study concluded that muscle endurance and weakness are associated with
LBP and that structural factors such as the size of the lumbar lordosis,
pelvic tilt, leg length discrepancy, and the length of abdominal, hamstring,
and iliopsoas muscles are not  associated with the occurrence of LBP.

Now, which therapists have been claiming how dangerous it is to have leg
length discrepancies and "shortened" muscles or distorted pelvic tilt?  How
many others have been playing around with blood pressure cuffs to show how
risky it allegedly is for the non-pathological individual to have large
"lumbar lordosis"?

-------------

J Orthop Sports Phys Ther 2002 Sept; 32(9):447-60

Relationship between mechanical factors and incidence of low back pain.

Nourbakhsh MR, Arab AM.

University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.

STUDY DESIGN: A multifactorial cross-sectional nonexperimental design.
OBJECTIVES: To collectively  investigate the association among 17 mechanical
factors and occurrence of low back pain (LBP).

BACKGROUND:  Several physical characteristics, based on assumptions,
clinical
findings, and scientific experiments, have been  associated with the
development of LBP Controversy exists regarding the degree of association
between some of  these physical characteristics and LBP. Information
regarding the degree of association of each factor to LBP is  needed for
effective prevention and appropriate treatment strategies.

METHODS AND MEASURES: A total of 600  subjects participated in this study.
Subjects were categorized into 4 groups: asymptomatic men (n = 150, age
[mean
 ± SD] = 43 ± 15 years), asymptomatic women (n = 150, age [mean ± SD] = 43 ±
13 years), men with LBP (n =  150, age [mean ± SD] = 43 ± 14 years), and
women with LBP (n = 150, age [mean ± SD] = 43 ± 13 years).  Seventeen
physical characteristics were measured in each group and the relative
association of each characteristic with  LBP was assessed.

RESULTS: Among all the factors tested, endurance of the back extensor
muscles
had the highest  association with LBP Other factors such as the length of
the
back extensor muscles, and the strength of the hip flexor,  hip adductor,
and
abdominal muscles also had a significant association with LBP.

CONCLUSION: It appears that muscle endurance and weakness are associated
with
LBP and that structural factors such as the size of the lumbar lordosis,
pelvic tilt, leg length discrepancy, and the length of abdominal, hamstring,
and iliopsoas muscles are not associated with the occurrence of LBP.

-----------------

Dr Mel C Siff
Denver, USA
http://groups.yahoo.com/group/Supertraining/