Four clinical tests for sacroiliac joints dysfunction, Artykuły, badania naukowe
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Four Clinical Tests of Sacroiliac Joint
Dysfunction: The Association of Test
Results With Innominate Torsion
Among Patients With and Without
Low Back Pain
Background and Purpose.
The purpose of this study was to assess the
association between innominate torsion (asymmetric anteroposterior
positioning of the pelvic innominates) and the Gillet, standing forward
flexion, sitting forward flexion, and supine-to-sit tests.
Subjects.
A
sample of 21- to 50-year-old patients with low back pain (n
5
138) were recruited from outpatient physical therapy facilities.
Methods.
The association of single and combined test results with
innominate torsion (calculated from pelvic landmark data) and with
presence or absence of low back pain were estimated via odds ratios,
sensitivities, specificities, and predictive values.
Results.
Individual test
sensitivities were low (8%– 44%), as were negative predictive values
(28%–38%), for identifying the presence of innominate torsion.
Combining tests and controlling for sex, age group, leg-length differ-
ence, or iliac crest level did not improve performance characteristics.
The associations of test results with low back pain were weak, with the
exception of the Gillet test (odds ratio
4.57).
Conclusion and Discus-
sion.
The data do not support the value of these tests in identifying
innominate torsion, although the use of these tests for identifying
other phenomena (eg, sacroiliac joint hypomobility) cannot be ruled
out. Further exploration of the association of Gillet test results with low
back pain is warranted. [Levangie PK. Four clinical tests of sacroiliac
joint dysfunction: the association of test results with innominate
torsion among patients with and without low back pain.
Phys Ther.
1999;79:1043–1057.]
5
Key Words:
Low back pain, Odds ratio, Sacroiliac joint, Tests and measurements.
Pamela K Levangie
Physical Therapy . Volume 79 . Number 11 . November 1999
1043
150) and
a comparison group of patients with upper-extremity impairments
(n
5
labels that have evolved since the turn of the
century to describe a fairly broad and poorly
defined group of signs and symptoms that are
usually thought to arise from the pelvic ring and sur-
rounding structures. Although recent studies
1–3
have
provided evidence that the sacroiliac joint may be a
source of low back pain (LBP) by demonstrating symp-
tom reduction after intra-articular injection of local
anesthetic, the source of pain or the tissues involved
remain unsubstantiated. One hypothesis is that pain
arises from tissues in the pelvis or the low back area that
are being stressed by asymmetry within the pelvic ring.
Anterior or posterior displacement (torsion) of one of
the innominates may cause a positional change within
one or both sacroiliac joints. This change may poten-
tially stress the structures attached to the innominates or
within the sacroiliac joints. Another theory of sacroiliac
joint pain is that sacroiliac joint hypomobility, with or
without concomitant innominate torsional asymmetry,
may cause LBP. This theory appears to assume that a
hypomobile sacroiliac joint may stress surrounding or
intervening tissues if one or both sacroiliac joints fail in
their presumed function of dissipating force from the
head and trunk above or from the ground below.
flexion test, the sitting flexion test (or Piedallu’s sign),
and the supine-to-sit test. These tests are also widely
promoted as part of a LBP examination in orthopedic,
osteopathic, physical therapy, and chiropractic educa-
tional texts.
13–21
Yet, there is neither consensus on nor
evidence to support the underlying hypotheses on which
these tests are based.
Although mechanisms to assess sacroiliac joint motion
do not currently exist, investigators using these tests and
those promoting test use in texts often suggest using one
or more of what they call “dynamic tests” (ie, standing
flexion test, sitting flexion test, Gillet test, and supine-
to-sit test) to detect hypomobility or motion asymmetry
of the sacroiliac joints.
9,17–19,21
Some authors
4,14,15,22
have
argued that the sitting flexion test detects hypomobility
of the sacrum on the ilium, whereas the standing flexion
test detects hypomobility of the ilium on the sacrum.
Other authors
10,15
have argued that one or more of these
tests can be used to detect the side of anterior or
posterior innominate torsion. Bemis and Daniel
4
found
the supine-to-sit test result to be related to a diagnosis of
iliosacral dysfunction (innominate torsion). They diag-
nosed iliosacral dysfunction using a composite finding of
positive standing PSIS asymmetry, a positive standing
flexion test, and a negative sitting flexion test. Delitto
et al
8
and Cibulka and colleagues
5,23,24
used a combina-
tion of 4 tests (3 of which must have positive findings) to
determine whether a person has sacroiliac joint dysfunc-
tion. Three of these tests were determination of PSIS
asymmetry in a sitting position, the standing flexion test,
and the supine-to-sit test. Cibulka and Koldehoff
24
pro-
posed that a positive standing flexion test indicated
hypomobility, whereas a positive supine-to-sit test indi-
cated both abnormal movement and malalignment
(innominate torsion). Sitting PSIS asymmetry was used
to detect malalignment.
24
Cibulka, in a published case
study, reported that the composite of 4 tests was used to
“determine whether innominate bone rotation was
The 2 hypotheses as to what causes sacroiliac pain
appear to be the bases for the classification of LBP as
being due to iliosacral dysfunction,
4
sacroiliac joint
dysfunction,
5– 8
lumbosacral dysfunction,
9
sacroiliac joint
malalignment,
10
sacroiliac hypermobility or hypomobil-
ity,
11
or sacroiliac regional pain.
12
Each of these classifi-
cation or diagnostic schemes is based on the assumption
that sacroiliac joint dysfunction can be identified by use
of tests to assess either innominate torsional asymmetry
or sacroiliac joint hypomobility. The common tests
include determination of posterior superior iliac spine
(PSIS) level in a standing or sitting position, the Gillet
test (also known as the march or stork test), the standing
PK Levangie, DSc, PT, is Associate Professor, Physical Therapy Program, Sacred Heart University, Fairfield, Conn. This research was completed
in partial fulfillment of the requirements for her Doctor of Science degree in epidemiology at Boston University’s School of Public Health, Boston,
Mass. Address all correspondence to Dr Levangie at 9 Cot Hill Rd, Bedford, MA 01730-1218 (USA) (levangiep@aol.com).
In addition to writing the article, Dr Levangie provided concept and research design, data collection and analysis, project management, and fund
procurement. Dr Levangie’s student research assistants contributed to data collection and clerical/secretarial support, and Dr Kenneth Rothman
supported data analysis. Subjects, facilities, and institutional liaisons were provided by staff of the participating physical therapy facilities
throughout the Boston area. Beth Israel Hospital and Brigham and Women’s Hospital provided key and long-term support. Dr Rothman and Dr
Nancy Watts provided consultation (including review of the manuscript prior to submission).
This study was approved by the Charles River Campus Institutional Review Board of Boston University and by the institutional review boards of
seven hospitals from which subjects were recruited.
This study received funding from the Foundation for Physical Therapy and was supported, in part, by Sargent
College of Allied Health Professions, Boston University, where Dr Levangie worked during part of the study period.
This article was submitted April 8, 1999, and was accepted June 6, 1999.
1044 . Levangie
Physical Therapy . Volume 79 . Number 11 . November 1999
S
acroiliac joint dysfunction is one of a variety of
present.”
23(p920)
Delitto and colleagues
8
used the tests as
part of their LBP classification system, but they did not
discuss the conceptual basis for the tests. They stated
that the tests are “purportedly directed toward dysfunc-
tion of the sacroiliac joints”
8(p478)
and that they “prefer
to state that a positive composite is indicative of need for
a specific manipulation technique.”
8(p478)
reliability and validity of data obtained with this tech-
nique are accepted, we would appear to have a standard
against which the Gillet, standing flexion, sitting flexion,
and supine-to-sit tests can be assessed as measures of
static or positional innominate torsion. Although such
an assessment ignores the issue of sacroiliac joint hypo-
mobility, there does not appear to be any viable method
for addressing this problem. Given the equivocal basis
for these tests, we gain information even if we are only
able to rule in or rule out one aspect of their perfor-
mance. As noted by Rothstein, “All evidence has limi-
tations, but whatever those limitations may be, data
are far better than debates that are more about
theology than they are about health care.”
35(p1044)
The
intent of this study, therefore, was to explore whether
the construct of innominate torsional asymmetry was
related to the outcome of 4 common clinical tests of
sacroiliac dysfunction.
The
Standards for Tests and Measurements in Physical Ther-
apy Practice
25
specify that research reports or scholarly
articles should address the theoretical basis for tests that
are used and should include a discussion of the evidence
relating to the construct validity and content validity of
the tests. The
Standards
further note that tests proposed
to classify people into diagnostic groups should include
essential elements to allow for interpretation, including
sensitivity, specificity, and predictive value. It is clear that
judgments of PSIS asymmetry, the Gillet test, the stand-
ing flexion test, and the supine-to-sit test have not met
these standards and that the specified information is
generally unavailable. One obvious reason for this dearth
of information is the lack of a gold standard against which
altered static or dynamic 3-dimensional relationships
within and around the sacroiliac joints and pelvic ring
can be assessed. Given the bicompartmental anatomy
and complex spatial relationships of the sacroiliac
joint,
26
it is not surprising that traditional imaging
procedures to date have been unable to provide a
noninvasive gold standard against which innominate
torsion or sacroiliac motion can be assessed. No studies
could be found that proposed a noninvasive external
standard of sacroiliac hypomobility that did not rely on
clinical judgments of positive-negative findings using
unvalidated test outcomes. In contrast, an acceptable
standard for assessing innominate torsion may be
available.
In my study, I used a cross-sectional approach with a
sample of adult patients seeking physical therapy ser-
vices: (1) to assess the magnitude of the association
between innominate torsion and the results of 4 clinical
tests of sacroiliac joint dysfunction, (2) to estimate the
performance characteristics (sensitivity, specificity, posi-
tive predictive value, and negative predictive value) of
these tests in identifying patients with innominate tor-
sion, and (3) to assess the magnitude of association
between the results of the clinical tests and nonspecific
LBP of less than 1 year’s duration.
Method
Choice of Clinical Tests
I identified 4 commonly used clinical tests of sacroiliac
joint dysfunction as the focus of this study: (1) the Gillet
test, (2) the standing flexion test, (3) the sitting flexion
test, and (4) the supine-to-sit test. This study was part of
a larger study I conducted to investigate the association
between estimated innominate torsional asymmetry and
LBP.
36
In the larger study, as well as in this study, PSIS
levels (or asymmetry) in standing and sitting positions,
unlike the other 4 tests, were measured rather than
assessed using clinical judgment. There also does not
appear to be any argument that PSIS asymmetry esti-
mates static (positional) changes in the innominates
rather than joint mobility. I also did not include clinical
tests designed to provoke symptoms, because provoca-
tion tests are used to determine whether the sacroiliac
region is a source of pain rather than to identify innom-
inate torsion (or hypomobility).
Pitkin and Pheasant
27
first proposed a mechanism for
measuring unilateral innominate inclination by assessing
pelvic landmarks. Their method or slightly modified
forms of the method were subsequently utilized and
accepted by other researchers
5,28 –32
as appropriate for
assessing either unilateral innominate inclination or
side-to-side innominate differences (innominate tor-
sion). Although there is no external standard against
which to validate this technique, assessing the inclina-
tion of anterior superior iliac spine (ASIS) and PSIS
landmarks unilaterally or bilaterally would appear con-
ceptually to be valid for assessing innominate inclina-
tion. The technique also is a more reliable way of
assessing innominate inclination than typically found
through palpation and clinical judgment alone. Using
this measurement technique, Walker and colleagues
33
found good intratester reliability of .84; other research-
ers,
31,34
however, found stronger intertester intraclass
correlation coefficients (ICCs) of .94 to .96. If the
Subjects
I recruited a sample of adult patients seeking physical
therapy services for this study. I chose a clinic-based sample
of patients with and without LBP because population-
Physical Therapy . Volume 79 . Number 11 . November 1999
Levangie . 1045
Table 1.
Exclusionary Criteria for Subjects With and Without Low Back Pain (LBP)
Exclusionary Criterion (by Self-Report)
Subjects
With LBP
Subjects
Without LBP
Current episode of LBP greater than 1 year in duration
x
Pain predominantly in middle back or neck rather than low back
x
Pain of traumatic origin (automobile accident or severe fall)
x
Pain of diskogenic origin as reported to subject by physician
x
Experienced LBP in the past year for which treatment was sought or that limited activity for more than a
couple of days
x
Receiving physical therapy for a lower-extremity problem
x
x
Unable to bend forward, stand, or sit for short periods without excessive pain or because of balance or
weakness problems
x
x
Past trauma or surgery to back, hips, pelvis
x
x
Known leg-length difference for which an orthosis or shoe lift was used
x
x
Known scoliosis or spinal anomalies
x
x
Pregnant
x
x
based subjects may differ in unknown ways from those
who actually seek medical attention, expend health care
dollars, and are managed by health care practitioners. I
recruited all subjects from the same facilities so that they
would be as alike as possible on uncontrolled variables
such as geographical distribution, socioeconomic group,
health care access, and willingness to seek medical care.
I set a lower age limit of 21 years to target subjects who
had reached skeletal maturity. I set an upper age limit of
50 years in an attempt to reduce the prevalence of
sacroiliac degenerative changes that are thought to
reduce sacroiliac mobility (and, perhaps, torsion) in
subjects after age 50 years.
37–39
estimated for the larger study to obtain a power of at
least 80%.
36
All subjects were recruited through outpa-
tient physical therapy facilities in 7 hospitals and 32
private practices serving a range of inner city and
suburban communities in the metropolitan Boston area.
Appointments for data collection were made at the
participating facility most convenient to the subject.
Subjects received $25 for participation. Recruitment and
enrollment was continued until the target sample of 150
subjects with LBP and 150 subjects without LBP was
reached.
Data Collection
During the data collection session, I or a research
assistant obtained informed consent and had each sub-
ject complete a self-administered questionnaire from
which descriptive data were obtained. I conducted a
physical examination in a fixed order for all subjects.
The examination consisted of measurements of the
height of the pelvic landmarks, iliac crest level, and leg
lengths and the 4 clinical tests of sacroiliac joint dysfunc-
tion. I served as the only examiner to avoid interrater
reliability issues. At the beginning of data collection, I
was usually unaware of whether subjects had LBP. To
reduce the possibility that patients’ behavior would
indicate whether they had LBP, I treated all subjects as if
they had LBP. All subjects were unknown to me, and I
performed only the measurements described in this
article. Consequently, my judgments of positive or neg-
ative test results were not influenced by patient history or
other evaluative findings.
The subjects with LBP were patients who had been
referred for physical therapy for LBP of less than 1 year’s
duration. I excluded patients with LBP of greater than 1
year’s duration because some experts contend that the
pain and disability experienced by people with LBP
becomes dissociated over time from the original physical
basis of the problem.
40
A comparison group of subjects
consisted of patients referred for physical therapy for an
upper-extremity problem whose diagnosis did not
appear to me to indicate that the problem was neck- or
back-related (eg, thoracic outlet syndrome). I excluded
people with upper-extremity problems who had been
treated for LBP within the previous year or had experi-
enced activity limitation due to LBP for more than a few
days in the previous year. This was done to avoid
including patients with low back dysfunction among the
comparison group. Exclusionary criteria for both groups
are presented in Table 1.
A sample size of 150 subjects with LBP and 150 subjects
without LBP was targeted. The number of subjects was
Measured Innominate Torsion
I began the determination of innominate torsion by first
measuring the heights of anterior (ASIS) and posterior
1046 . Levangie
Physical Therapy . Volume 79 . Number 11 . November 1999
Figure 2.
As the examiner actively hooked her thumb beneath the landmark, the
horizontal arm was brought to the height of a mark bisecting the
examiner’s thumbnail longitudinally. Once the arm position was
secured, the height reading was obtained off the graduated post.
Figure 1.
A pedestal-mounted post with an adjustable horizontal arm was used to
measure heights of palpated landmarks (in millimeters).
twice. The height markings on the post were out of my
line of sight and were not observed until the position of
the horizontal arm had been set. The arm was dropped
down after recording the first measurement and reposi-
tioned for the second measurement, again without being
able to see the height markings until after the arm was
fixed in position. In addition to obtaining repeated
landmark measurements, I calculated innominate tor-
sion first using the first set of landmark heights and then
again using the second set of landmark heights. For the
remaining analyses, the average of the 2 measurements
was used for calculations. I chose to consider the stan-
dard error of the measurement to be the cutoff value for
identifying the presence or absence of innominate tor-
sion. That is, any calculated torsion greater than the
standard error would be positive torsion (asymmetric
innominates) and any torsion at or below the standard
error would be negative torsion (symmetric innomi-
nates). The standard error of the innominate torsion
measurement was estimated as the square root of the
mean square error from the repeated-measures analysis
of variance.
41
(PSIS) pelvic landmarks on each side. To obtain height
measurements, I hooked my thumb beneath each bony
prominence while the horizontal arm of a pedestal-
mounted post was brought to a line marking the mid-
point of my thumbnail (Figs. 1 and 2). These height
values were then used to calculate the difference
between PSIS and ASIS heights on the right innominate
(right PSIS
2
left ASIS). To determine innominate asymmetry,
I calculated the absolute difference between the right
PSIS/ASIS difference and the left PSIS/ASIS difference.
That is, I estimated innominate torsional asymmetry
using the following formula: Estimated Innominate
Torsion
5
Absolute [(Right PSIS
2
Right ASIS)
2
In addition to measuring PSIS and ASIS heights and
calculating innominate torsion, I also measured leg
lengths and determined iliac crest levels while subjects
were standing and iliac crest levels while subjects were
sitting. These variables allowed me to explore whether
asymmetry of leg lengths or iliac crests might affect the
results of the tests. I measured leg lengths with the
subjects positioned supine, using a cloth tape measure to
measure the distance from the ASIS to the lateral
malleolus.
42
Leg lengths were each measured twice to
permit estimates of reliability. The markings on the tape
measure were not observed for either the first of second
measurement until my hand positions on the tape
Left ASIS)]. The method of landmark
measurement and the innominate torsion calculation I
chose were based on principles and techniques used and
accepted by other researchers
29 –31,33,34
as reliable and as
representative of innominate inclination. To obtain esti-
mates of reliability and standard error of the measure-
ment for locating anatomical landmarks and calculated
innominate torsion, I measured each landmark height
2
Physical Therapy . Volume 79 . Number 11 . November 1999
Levangie . 1047
right ASIS) and the difference between
PSIS and ASIS landmarks on the left innominate (left
PSIS
2
(Left PSIS
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