1. No category

Reliability of Clinical Measurements of Lumbar
Lordosis Taken with a Flexible Rule
Franklin W Lovell, Jules M Rothstein and Walter J
Personius
PHYS THER. 1989; 69:96-102.
The online version of this article, along with updated information and services, can
be found online at: http://ptjournal.apta.org/content/69/2/96
Collections
This article, along with others on similar topics, appears
in the following collection(s):
Injuries and Conditions: Low Back
Tests and Measurements
e-Letters
To submit an e-Letter on this article, click here or click on
"Submit a response" in the right-hand menu under
"Responses" in the online version of this article.
E-mail alerts
Sign up here to receive free e-mail alerts
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
Reliability of Clinical Measurements of Lumbar Lordosis
Taken with a Flexible Rule
The purpose of this study was to examine the intratester and intertester reliability
of lumbar lordosis measurements taken with a flexible rule. Two physical
therapists (Tester 1 and Tester 2) took measurements on 40 subjects without low
back pain (LBP) and on 40 subjects with LBP. Intraclass correlation coefficients
(ICCs) were used to determine the degree of agreement between repeated
measurements taken by the same therapist and between measurements taken by
the two therapists. The ICC values for intratester reliability of Tester 1 were .84 for
subjects without LBP and .94 for subjects with LBP. The ICC values of Tester 2
were . 73 for subjects without LBP and .83 for subjects with LBP. Intertester
reliability generally was poor, with ICC values of .41 for subjects without LBP and
.50 for subjects with LBP. The results suggest that measurements of lumbar lordosis
with a flexible rule may be reliable if taken by the same physical therapist. The
degree of reliability, however, may vary from therapist to therapist. The intertester
reliability of these measurements appears to be poor, but these conclusions must
be interpreted carefully because of the limited number of therapists participating
in this study. [Lovell FW, RothsteinJM,Personius WJ: Reliability of clinical
measurements of lumbar lordosis taken with a flexible rule. Phys Ther 69:96-105,
1989.]
Franklin W Lovell
Jules M Rothstein
Walter J Personius
Key Words: Backache; Lordosis; Lumbar vertebrae; Tests and measurements,
general.
Physical therapists frequently evaluate
and treat patients with low back pain
(LBP). During the therapist's evaluation,
the extent of lumbar lordosis is often
assessed.1-3 This assessment often
consists of visual inspection. The
patient often is then classified as having
a specific type of posture.4,5 This
assessment is then used by some
therapists to determine the choice of
treatment programs.4,5 However, to
provide meaningful and accurate
information on which to base
assessments and treatment selection,
measurements must be reliable and
valid. The reliability of techniques to
F Lovell, MS, is Chief, Physical Therapy Services, 92nd Strategic Hospital/SGHY, Fairchild Air Force
Base, WA 99011 (USA). He was a master's degree candidate, Program in Physical Therapy, Medical
College of Virginia, Virginia Commonwealth University, when this research was completed in partial
fulfillment of the requirements for his master's degree. Address correspondence to Major Lovell.
assess lumbar lordosis based on visual
inspection has not been demonstrated.
In addition, visual inspection does not
provide quantitative information about
the lumbar lordosis.
Several measurement techniques have
been described for quantifying lumbar
lordosis. These techniques include the
use of radiographs,6 photographs,7,8 the
Iowa Anatomical Positioning System
(IAPS),9 posture meters,10 specialized
goniometers,8 and flexible rules.11-13
Repeated radiographs are expensive
and pose a potential health hazard to
the patient.14 Photographs are
W Personius, PhD, is Associate Professor, Department of Physical Therapy, School of Allied Health
expensive, and studies have not
Professions, Medical College of Virginia, Virginia Commonwealth University.
demonstrated a high degree of validity
for these methods.7,8 The IAPS, posture
The opinions expressed herein are solely those of the authors and may not be construed as an official
position of the US Air Force Medical Service or the Department of Defense.
meters, and specialized goniometers
are
not readily available to clinicians.
This article was submitted August 3, 1987; was with the authors for revision for 31 weeks; and was
J Rothstein, PhD, is Associate Professor, Department of Physical Therapy, School of Allied Health
Professions, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA 23298.
accepted May 27, 1988.
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
96/13
On the other hand, the flexible rule
has no safety problems and is
inexpensive, readily available, and easy
to use.11 However, reliability and
validity of the flexible rule have not
been shown on clinically relevant
populations. This documentation is
necessary if the measurements are to
be meaningful to clinicians.
reported an ICC of .97 for 23 pairs of
repeated measurements taken on
subjects who were either standing or
maximally forward bent. The type of
subjects measured was not described,
and the reliability for each position was
not reported. Hart and Rose appear to
have used a form of the ICC that tends
to overestimate reliability.15 In addition
to examining reliability, Hart and Rose
examined the validity of the
flexible-rule measurements using data
from six of their subjects. They
compared the measurements they
obtained using aflexiblerule with two
different measurements they made
from radiographs. The Pearson
product-moment correlations between
each of the two methods and the
flexible-rule measurements were .87
and .51, respectively. Based on their
results, Hart and Rose concluded that
theflexible-rulemethod had good
intratester reliability and validity.
Walker et al reported an intraclass
correlation coefficient (ICC) (formula
of Shrout and Fleiss [1,1])15 of .90 for
intratester reliability of measurements
of lumbar lordosis using aflexiblerule
on 31 young, healthy physical therapy
students.12 The ICC was used to
determine the degree of agreement
between paired measurements. They
concluded that their measurements
were reliable on young, healthy
subjects. We found no published
studies that examined the intertester
reliability of measurements of lumbar
lordosis using the flexible rule on
patient populations.
Intertester reliability is important if two
or more examiners are measuring the
same subject or exchanging data. In
addition, reliability demonstrated for
one type of subject cannot be assumed
Hart and Rose studied the reliability of
measurements obtained by a single
tester with aflexiblerule.13 They
to be present for another type of
subject.16 Therefore, even though
measurements obtained using a flexible
rule on healthy subjects appear to be
reliable, they may not be reliable on
patients with LBP. Patients with LBP are
commonly assessed and treated by
physical therapists. Therefore,
determination of the reliability of
measurements obtained with a flexible
rule on patients with LBP is needed.
The purpose of this study was to
determine intratester and intertester
reliability of lumbar lordosis
measurements using aflexiblerule on
subjects with LBP and on subjects
without LBP. Specifically, the degree of
reliability was assessed for 1) repeated
measurements of lumbar lordosis taken
with aflexiblerule by the same
therapist on subjects without LBP, 2)
repeated measurements of lumbar
lordosis taken with aflexiblerule by
the same therapist on subjects with
LBP, 3) measurements of lumbar
lordosis taken with aflexiblerule by
two different therapists on subjects
without LBP, and 4) measurements of
lumbar lordosis taken with a flexible
rule by two different therapists on
subjects with LBP.
Method
T a b l e 1.
Characteristics of Subjects
Subjects
a
Variable
NSLBP Group
(n = 40)
b
SLBP Group
(n = 40)
Men
20
15
Women
20
25
30
40
Age (yr)
s
Range
10
11
(20-61)
(24-68)
147
161
23
31
Weight (lbc)
s
Range
(98-195)
(114-233)
172.7
167.6
Height (cm)
s
Range
a
Nonsignificant low back pain.
b
Significant low back pain.
c
1 lb = 0.4536 kg.
14/97
10.2
(152.4-193.0)
10.2
(152.4-185.4)
Subjects for this study consisted of two
groups of 40 volunteers who were
patients, students, or staff members at
the Medical College of Virginia,
Richmond, Va. The first group
consisted of 40 volunteers who did not
have low back pain and who had
limited work or recreational activities
or required medical care within the
past 12 months. This group was
referred to as the Nonsignificant Low
Back Pain (NSLBP) Group. The second
group consisted of 40 volunteers with
LBP. We defined low back pain as pain
in the lower third of the back that
resulted in the patient limiting work or
recreational activities or that caused the
patient to seek medical help during the
past 12 months. This group was
referred to as the Significant Low Back
Pain (SLBP) Group. None of the female
subjects reported being pregnant at the
time of the study, and volunteers who
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
Fig. 1. Photograph offlexiblerule.
reported a history of lumbar spinal
fusions, connective tissue diseases, or
neurological diseases were excluded
from the study. All subjects gave
informed consent before participation
in the study. Table 1 describes the
characteristics of the subject groups.
increments was used to measure
distances on the tracings. The data
obtained from these instruments were
used to calculate the angle of the
lumbar lordosis.
Testers
The procedure was a modification of a
method described by Walker et al.12
The subjects were asked to stand in a
relaxed position with the low back and
upper buttocks exposed. The subjects
were told to distribute their weight
evenly, with their feet 10 to 15 cm
apart. The subjects stood with their
arms at their sides and their head
facing forward. A tracing was then
made of the position of the subjects'
feet on a piece of paper on the floor.
This procedure allowed repeated
measurements of the lumbar lordosis
to be made with the subjects' feet in
the same position.
Measurements of the lumbar lordosis
were made by two physical therapists.
Tester 1 (FWL) had nine years of
clinical orthopedic physical therapy
experience and was a graduate physical
therapy student at the time of the study.
Tester 2 had eight years of clinical
orthopedic physical therapy experience
and was the Orthopedic Clinical
Supervisor at the Medical College of
Virginia at the time of the study. Each
tester served as his or her own
recorder. Both testers independently
practiced taking measurements on five
subjects before the study.
Instrumentation
Aflexiblerule* was used to obtain
tracings of the lumbar lordosis of each
subject (Figure 1). Small adhesive
markers with a horizontal line drawn
through the center were used to mark
the spinous processes of L3 and S2. A
straight ruler marked in 1-mm
Procedure
The tester palpated the spinous
processes of L3 and S2 and marked
them with small paper adhesive
markers. The spinous process of L3 was
located using the following method.
The L4-5 interspace was located on an
imaginary line approximately midway
between the superior aspect of the two
iliac crests.17 The tester then palpated
two spinous processes up from this
space to locate the L3 spinous process.
A marker was placed over this process
making sure the line on the marker
was horizontal. Next, the examiner
palpated the S2 spinous process, which
was assumed to be midway between
the inferior aspects of the posterior
superior iliac spines (PSISs).17 This
assumption was made because of the
difficulty in identifying this spinous
process. An adhesive marker was
placed over the center of the S2
spinous process keeping the line on
the marker horizontal.
The flexible rule was then placed over
the spinous processes of the low back
and shaped to fit its contour. The
markings on the flexible rule that
intersected with the lines on the
adhesive markers at the L3 and S2
spinous processes were noted. The
tester then carefully removed the
flexible rule so as not to distort its
shape. The outline of the curve was
traced onto paper, and the markings
that corresponded to the L3 and S2
levels were labeled as points A and B,
respectively (Figure 2). To reduce
examiner bias, all measurements from
tracings were calculated randomly after
all subjects were measured. The testers
calculated their own measurements.
The length of the line (L) drawn from
point A to point B was measured to the
nearest millimeter (Figure 2). The
length of a perpendicular line (H)
drawn from the midpoint of L to the
*Model TC-384, C-Thru Ruler Co, 6 Britton Dr, Bloomfield, CT 06002.
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
98/15
Intertester reliability. After being
measured two consecutive times by the
first tester, the subjects were given a
one- to three-minute rest. Each subject
was then measured by the other tester,
who used the same procedure,
including making a tracing of the
position of the subjects' feet. Tester 1
measured all subjects first, followed by
Tester 2. Each tester measured all 40
subjects in each group.
measurements of theta by Tester 1
were .84 for the NSLBP Group and .94
for the SLBP Group (Tab. 2). The ICC
values for Tester 2 were .73 for the
NSLBP Group and .83 for the SLBP
Group (Tab. 2). The ICC values for
intertester reliability using first
measurements taken by each therapist
were .41 for the NSLBP Group and .50
for the SLBP Group (Tab. 3). The ICC
values for intertester reliability using
the second set of measurements taken
by each therapist were .54 for the
NSLBP Group and .52 for the SLBP
Group (Tab. 3).
Data Analysis
θ = 4 x [arctan (2H/L)]
F i g . 2 . Drawing to depict length (L)
and height (H) of curve used to calculate
theta. (A corresponds to L3 spinous process;
B corresponds to S2 spinous process.)
curve (Fig. 2) was then measured with
a ruler to the nearest millimeter. This
distance represented the height of the
curve. These two measurements (L and
H) were then recorded on the data
form by the tester performing the
measurements. An angle, theta (θ), 18
was then determined by using these
measurements in the equation:
0 = 4 x [arctan(2H/L)]
where 6 represents the magnitude of
the lordotic curve.
Intratester reliability. After this
procedure was performed, the markers
were removed, and the subjects were
given a one-minute rest. The subjects
were then asked to stand with their feet
in the same position as for the first
measurement. This positioning was
controlled by having the subjects place
their feet on the outline drawn before
the first measurement was taken. We
believe that clinicians who use the
flexible rule should control for subject
foot position when taking serial
measurements and that the use of a
tracing is a practical means for
achieving this goal. The procedure
previously described was then used to
obtain a second measurement of theta.
Intratester reliability was determined
for both testers on each of the 40
subjects in each group. Only one tester
was present in the examination room
at a time.
Intraclass correlation coefficients15 were
calculated to describe the degree of
agreement for the repeated measures
(ie, for intratester reliability, the paired
measurements taken by each therapist,
and for intertester reliability, the paired
measurements taken by the two
therapists). We were interested in only
the error associated with repeated
measures and not the effects of each
tester. Therefore, the form of ICC
described by Shrout and Fleiss in
equation 1,1 was used.15 Calculation of
the ICC for intratester reliability was
made by comparing paired
measurements taken by each tester.
There were 40 pairs of measurements
for Tester 1 and 40 pairs of
measurements for Tester 2 for each
subject group. Calculation of the ICC
for intertester reliability was made by
comparing the first measurements
taken by each tester.
Discussion
Measurements of lumbar lordosis
obtained with a flexible rule appear to
be reliable when repeated by the same
tester over a short period of time (Tab.
2). This observation is based on the
high ICCs for intratester reliability of
theta measurements for Tester 1.
Intratester reliability of theta
measurements by Tester 2 were
considerably lower (Tab. 2).
The ICC values obtained by Tester 1
were similar to the ICC value of .90
Walker et al found for repeated
measures in 31 young, healthy physical
therapy students.12 Hart and Rose also
obtained a high ICC value for
intratester reliability.13 However, Hart
and Rose did not report separate values
for the measurements of standing and
forward-bent subjects. They also used a
less conservative form of the ICC than
was used in our study and by Walker et
al.12 Therefore, their results may have
Results
Results based on ICC values showed
that intratester reliability for the
Table 2.
Intraclass Correlation Coefficienta for Intratester Reliability
NSLBPb Group
(n = 40)
SLBPC Group
(n = 40)
T1d
T2e
T1
T2
T1
T2
Length
.92
.90
.92
.91
.96
.80
.84
.97
.72
.94
Height
.77
.88
.74
.73
.94
.83
.91
.78
Theta
a
d
b
Shrout and Fleiss equation (1,1).15
e
Nonsignificant low back pain.
Combined Groups
(N = 80)
Therapist 1.
Therapist 2.
c
Significant low back pain.
16/99
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
Table 3- Intraclass CorrelationCoefficientsafor Intertester Reliability
NSLBPb Group
(n = 40)
SLBPC Group
(n = 40)
Combined Groups
(N = 80)
Length 1
.70
.52
.62
Height 1
.32
.38
.35
Theta 1
.41
.50
.46
Length 2
.73
.43
.60
Height 2
.36
.50
.44
Theta 2
.54
.52
.53
healthy subject by 10 different
examiners.
The low ICC values for intratester
reliability of Tester 2 appear to have
contributed to the poor intertester
reliability. The use of only two
therapists in our study, however, makes
it difficult to generalize our intertester
reliability results to the general
population of therapists. Therefore,
using a greater number of therapists to
measure subjects would have enabled
us to more adequately assess intertester
reliability.
a
Shrout and Fleiss equation (1,1).15
b
Nonsignificant low back pain.
c
Significant low back pain.
overestimated the degree of reliability
because they used a questionable
statistic.
One possible explanation for lower
ICC values of Tester 2 could be error
in measuring the height of the curve.
Intratester reliability for measurements
of curve length was good for both
therapists (Tab. 2). However, intratester
reliability of height measurements for
Tester 2 was much lower than it was
for Tester 1 (Tab. 2).
During the study, we noted that a
difference in height of 1 mm could
affect the value of theta by as much as
10 degrees. Because the height had a
smaller excursion (range of values)
than the length, and because it was
multiplied by a factor of 2 in the
equation to determine theta, small
variations in height greatly affected the
value generated by the equation. As a
result, even small differences in the
height measurement could result in
very different values for theta. These
differences could possibly have
resulted in lower intratester reliability
based on ICC values for measurements
of theta by Tester 2.
Other possible explanations also exist
for the lower ICC values of Tester 2.
Tester 2 performed measurements for
this study while treating patients and
performing administrative duties. Many
times she had to interrupt a patient's
treatment session or leave a meeting to
obtain measurements. These
interruptions caused her to be rushed
at times during the measurement
process. Tester 1, on the other hand,
was a full-time graduate student whose
only requirement was to collect data.
He did not have time constraints and
was not rushed. Therefore, he took
between 5 and 10 minutes to perform
each measurement. Both therapists had
similar experience in orthopedic
clinical work. However, Tester 1 was
more knowledgeable and familiar with
the measurement procedures using a
flexible rule than Tester 2.
Subject fatigue may also have been a
factor leading to decreased reliability.
The subjects may have become tired
during the period of time required for
Tester 1 to measure the patients.
Fatigue may have resulted in subjects
being unable to maintain their posture
during the measurements taken by
Tester 2. This factor could have
diminished the intratester reliability of
Tester 2 and the intertester reliability.
Intertester reliability for all
measurements of lumbar lordosis was
generally poor (Tab. 3). The ICC values
for intertester reliability of the second
measurements were higher than for the
first measurements, but the reliability
was still poor (Tab. 3). These values
were much lower than those found by
Henkel (Barbara A Henkel,
unpublished data, 1985). Henkel
reported an ICC of .70 for the
intertester reliability of lumbar lordosis
measurements obtained from a single
Another possible source of error
affecting intertester reliability may have
been errors by the testers in not
locating the same bony landmarks. If
the testers were not consistent in
locating the same landmarks, this
inconsistency could have resulted in
the testers measuring different curves
and obtaining different values. For
example, if Tester 1 labeled the L2
spinous process as L3 and Tester 2
labeledLAas L3, the length and height
of the curve would be different and
could result in different values for
theta. As can be seen in Table 3, the
ability of the testers to agree on the
length and height was poor, indicating
a possible problem in locating the
same bony landmarks.
An additional source of error affecting
intertester reliability may have been
some differences in the way the
subjects stood while being measured
by each tester. Foot tracings were taken
by each tester to ensure that the subject
stood similarly during each
measurement by the same tester.
However, the therapists took their own
tracings.
The SLBP Group demonstrated higher
intratester reliability than the NSLBP
Group (Tab. 2). This 10% difference
appears to represent a meaningful
difference. The higher ICC values for
intratester reliability of the SLBP Group
could be a result of a more rigid
posture associated with patients with
LBP.
Good intratester reliability of
measurements of the lumbar lordosis
by Tester 1 suggests that the flexible
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
100/17
subject fatigue. Our results demonstrate
the need for therapists to determine
their own intratester reliability before
using measurements of lumbar lordosis
obtained with a flexible rule.
T a b l e 4. Intraclass Correlation Coefficientsa for Intratester Reliability as a Result of
Certain Factors
SLBPC Group
NSLBPb Group
Factor
T1d
T2 e
N
T1
T2
Male
.88
.58
20
.88
.83
15
Female
.78
.76
20
.93
.74
25
Age <33 yr
.78
.95
33
.95
.83
15
Age >33 yr
.90
.93
7
.94
.81
25
Previous LBP
.91
.82
20
No previous LBP
.96
.81
20
Pain <3 f
.88
.73
17
Pain >3
.96
.84
23
a
e
b
Shrout and Fleiss equation (1,1).15
f
N
Therapist 2.
Nonsignificant low back pain (LBP).
Pain was measured by asking the subject to
mark the pain intensity on a 10-cm line.
c
Significant LBP.
d
Therapist 1.
rule may be useful when taking
measurements on a subject by the
same tester. This utility may be
clinically relevant by enabling a
physical therapist to note changes in
lumbar lordosis as a result of
treatment. However, functional criteria
would still be necessary to validate
whether a treatment was helpful to a
patient. The following factors may have
had an effect on reliability: the tester's
expertise in using the flexible rule, the
amount of time available to take
measurements, and the effects of
T a b l e 5 . Intraclass Correlation Coefficientsa for Intertester Reliability as a Result of
Certain Factors
Factor
NSLBPb
Group
.35
Male
N
SLBPC
Group
N
20
.73
15
25
Female
.36
20
.34
Age <33 yr
.48
33
.61
15
Age >33 yr
.38
7
.44
25
Previous LBP
.70
20
No previous LBP
.36
20
d
.45
17
Pain >3
.54
23
Buttock pain
.60
27
Thigh pain
.71
20
Leg pain
.57
15
Pain < 3
Poor intertester reliability of lumbar
lordosis measurements also has
important clinical implications. If
intertester reliability of measurements
of lumbar lordosis is poor, a patient
seen by two or more therapists might
receive different treatments. For
example, one therapist may measure a
small amount of lumbar lordosis and
prescribe McKenzie's extension
exercises4 to increase the amount of
lordosis. Another therapist, however,
after measuring the same patient, might
find a great deal of lordosis and
prescribe Williams's flexion exercises.5
In addition to this problem, poor
intertester reliability for measurements
of lumbar lordosis could impede
communications between physical
therapists. Measurements reported by
one therapist could not be used by
another. Therefore, a therapist may not
be able to describe the lumbar lordosis
using measurement values of an
unreliable measurement method.
In an attempt to identify factors that
may have affected reliability, a
posteriori analyses were performed.
The variables that were examined for
effects on reliability were subject's sex,
age, pain level, and history of previous
LBP. Pain level was determined during
the initial assessment by asking the
subjects with LBP to mark the level of
pain on a 10-cm line. Intratester
reliability did not appear to be affected
to any significant degree by any of
these factors (Tab. 4). These factors
appeared to have had a small effect on
intertester reliability. However, even
considering these effects, the ICC
values were still poor (Tab. 5). In
addition, the number of subjects in
some of these categories was too
small to make any definite
conclusions (Tab. 5).
Conclusions
a
Shrout and Fleiss equation (1,1).15
b
Nonsignificant low back pain (LBP).
c
Significant LBP.
d
Pain was measured by asking the subject to mark the pain intensity on a 10-cm line.
18/101
Clinical measurements of lumbar
lordosis using a flexible rule can be
highly reliable if taken by the same
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
therapist over a short period of time.
However, this statement may not be
true for all therapists. The level of
expertise in using the flexible rule,
time available to take measurements,
and subject fatigue may also influence
reliability. Therefore, intratester
reliability should be assessed for each
therapist before using this procedure.
This precaution appears to be true for
measuring both subjects with
significant LBP and those without
significant LBP.
Clinical measurement of lumbar
lordosis using the flexible rule cannot
be considered reliable between
therapists. Our results strongly suggest
that measurements of the lumbar
lordosis using a flexible rule should be
made by the same tester. Additional
studies involving a greater number of
testers are needed to more clearly
assess intertester reliability.
Acknowledgments
We thank Delores Nice, PT, and the
staff of the Physical Therapy
Department, Medical College of
Virginia Hospital, Richmond, Va, for
their assistance in this study and
Thomas P Mayhew, PT, and Dan L
Riddle, PT, for their assistance with this
manuscript.
References
1 Corrigan B, Maitland GD: Practical
Orthopaedic Medicine. Boston, MA, Butterworth
Publishers, 1983
2 Cyriax J: Textbook of Orthopaedic Medicine:
Diagnosis of Soft Tissue Lesions, ed 8. London,
England, Baillière Tindall, vol 1, 1982
3 Grieve GP (ed): Common Vertebral Joint
Problems. London, England, Churchill
Livingstone, 1981
4 McKenzie RA: Manual correction of sciatic
scoliosis. N Z Med J 76:194-199, 1972
5 Williams PC: The Lumbosacral Spine:
Emphasizing Conservative Management. New
York, NY, McGraw-Hill Inc, 1965
6 Farfan HF: Mechanical Disorders of the Low
Back. Philadelphia, PA, Lea & Febiger, 1973
7 Flint MM: Lumbar posture: A study of
roentgenographic measurement and the
influence of flexibility and strength. Research
Quarterly 34:15-20, 1963
8 Burdett RG, Brown KE, Fall MP: Reliability and
validity of four instruments for measuring
lumbar spine and pelvic positions. Phys Ther
66:677-684, 1986
9 Day JW, Smidt GL, Lehmann T: Effect of pelvic
tilt on standing posture. Phys Ther 64:510-516,
1984
10 Harris R: A simple posture meter. Ann
Rheum Dis 14:90-91, 1955
11 Israel M: A quantitative method of estimating
flexion and extension of the spine: A
preliminary report. Milit Med 124:181-186, 1959
12 Walker ML, Rothstein JM, Finucane SD, et al:
Relationships between lumbar lordosis, pelvic
tilt, and abdominal muscle performance. Phys
Ther 67:512-516, 1987
13 Hart DL, Rose SJ: Reliability of a non-invasive
method for measuring the lumbar curve. Journal
of Orthopaedic and Sports Physical Therapy
8:180-184, 1986
14 Russell JG: How dangerous are diagnostic
x-rays? Clin Radiol 35:347-351, 1984
15 Shrout PE, Fleiss JL: Intraclass correlations:
Uses in assessing rater reliability. Psychol Bull
86:420-428, 1979
16 Rothstein JM: Measurement and clinical
practice: Theory and application. In Rothstein JM
(ed): Measurement in Physical Therapy: Clinics
in Physical Therapy. New York, NY, Churchill
Livingstone Inc, 1985, vol 7, pp 1-46
17 Hoppenfeld S: Physical Examination of the
Spine and Extremities. New York, NY,
Appleton-Century-Crofts, 1976
18 Shelby SM (ed): CRC Mathematical Tables,
ed 21. Cleveland, OH, Cleveland Press, 1973
Commentary
The authors should be complimented
on their meticulous study of intratester
and intertester reliability of the external
shape of the lumbar spine, particularly
of patients with low back pain
syndrome. Exacting clinical and
research procedures such as the
procedure described in this article
should act as an example for other
clinicians and researchers so that the
readers can easily interpret the results
of research articles in such a way that
they can decide whether the findings
should be applied to their specific
patients and whether the investigation
can be duplicated if necessary.
Of particular clinical importance, the
article represents an example of how
to quantify a specific clinical
observation, in this case, the shape of
the lumbar spine, which has not been
shown to be reliable without such
quantification. For this fact alone, the
authors deserve recognition. It should
be emphasized that without these types
of investigations, the physical therapy
profession runs the distinct risk of
losing much of its support. The
insurance industry, for example,
because it has not had the justification
for the use of physical therapy services
previously, has simply begun to stop
remunerating physical therapists for
many services. Therefore, the authors
deserve our respect for this study.
However, as with all reliability studies,
if the reliable measurement is not used
now to answer appropriate clinical
questions, particularly after appropriate
validity studies, the efforts to determine
the reliability of the measurement will
have been for naught.
Because we have known that the
flexible ruler can be used to assess
both intratester and intertester
reliability and to reliably measure
inanimate objects,1 healthy subjects,1,2
and patients with low back pain,3-5 the
findings of this study are not new.
However, the article stimulates debate
that is fruitful in the analysis of this and
Physical Therapy/Volume 69, Number 2/February 1989
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014
102/19
Reliability of Clinical Measurements of Lumbar
Lordosis Taken with a Flexible Rule
Franklin W Lovell, Jules M Rothstein and Walter J
Personius
PHYS THER. 1989; 69:96-102.
http://ptjournal.apta.org/subscriptions/
Subscription
Information
Permissions and Reprints http://ptjournal.apta.org/site/misc/terms.xhtml
Information for Authors
http://ptjournal.apta.org/site/misc/ifora.xhtml
Downloaded from http://ptjournal.apta.org/ by guest on September 9, 2014