Data from the
National Health Interview Survey of the U.S. population in 2006
suggests that 27.4% of the US population ages 18 and older
experienced low back pain. Given this high percentage for
individuals who experience low back pain, it is not surprising that
low back pain is a common condition treated in physical therapy.
When physical therapists evaluate patients with low back pain they
not only perform a detailed examination and assessment to determine
organic problems which indicate the presence of pathology or
disease, but they also consider psychological factors which could be
contributing to the pain as well (1). Often times when conducting an
examination on a patient with low back pain, physical therapists may
also come across nonorganic signs as well. These nonorganic signs
are findings which differ from the common characteristics of a
disease or condition (1, 2, 3).
One such tool utilized to screen patients with low back pain for
nonorganic signs was developed by Waddell et al. (2). These
researchers developed a standardized group of five types of physical
signs to screen for nonorganic low back pain. These physical signs
include: tenderness, simulation tests, distraction test, regional
disturbances and overreaction. Any individual sign counts as a
positive sign for that type; a finding of three or more of the five
types is clinically significant for non-mechanical, pain-focused
behavior. A single positive sign, however, is ignored. Below is a
more detailed description of these signs:
1) Tenderness (from table of Scalzitti DA (1) adapted from
Waddell et al (2))
Tenderness not related to a particular skeletal or neuromuscular
structure; may be either superficial or nonanatomic.
Superficial – The skin in the lumbar region is tender to light pinch
over a wide area not associated with the distribution of the
posterior primary ramus.
Nonanatomic – Deep tenderness, which is not localized to one
structure, is felt over a wide area and often extends to the
thoracic spine, sacrum or pelvis.
2) Simulation Tests
(from table of Scalzitti DA (1) adapted
from Waddell et al (2))
These tests give the patient the impression that a particular
examination is being carried out when in fact it is not.
Axial Loading – Low back pain is reported when the examiner presses
down on the top of the patient’s head; neck pain is common and
should not be indicative of a nonorganic sign.
Rotation – Back pain is reported when the shoulders an pelvis are
passively rotated in the same plane as the patient stands relaxed
with the feet together; in the presence of root irritation, leg pain
may be reproduced and should not be indicative of a nonorganic sign.
3) Distraction Test
(from table of Scalzitti DA (1) adapted
from Waddell et al (2))
A positive physical finding is demonstrated in the routine manner,
and this finding is then checked while the patient’s attention is
distracted; a nonorganic component may be present if the finding
disappears when the patient is distracted.
Straight Leg Raising – The examiner lifts the patient’s foot as when
testing the plantar reflex in the sitting position; a nonorganic
component may be present if the leg is lifted higher than when
tested in the supine position.
4) Regional Disturbances
(from table of Scalzitti DA (1)
adapted from Waddell et al (2))
Dysfunction (eg, sensory, motor) involving a widespread region of
body parts in a manner that cannot be explained based on anatomy;
care must be taken to distinguish from multiple nerve root
involvement.
Weakness – Demonstrated on testing by a partial cogwheel “giving
way” of many muscle groups that cannot be explained on a localized
neurological basis.
Sensory – Include diminished sensation to light touch, pinprick or
other neurological tests fitting a “stocking” rather than a dermatomal pattern.
5) Overreaction (from table of Scalzitti DA (1) adapted from
Waddell et al (2))
May take the form of disproportional verbalization, facial
expression, muscle tension and tremor, collapsing, or sweating;
judgments should be made with caution, minimizing the examiner’s own
emotional reaction.
One research study found that Waddell’s signs was a useful tool to
be utilized in the physical therapy setting to predict return to
work. In a study conducted by Karas et al. (3) they assessed the
relationship between the nonorganic signs (Waddell scores) of
patients with low back pain, their response to repetitive end range
lumbar spine test movements (centralization of symptoms), and the
rate of return to work at a 6 month follow up. In this study, their
original sample size comprised of 171 consecutive patients with low
back pain were assessed by experienced physical therapists for
responses to repetitive test movements (centralization as described
by McKenzie) and for nonorganic signs (Waddell scores). These
therapists completed a data sheet that classified patients as either
those who centralize their symptoms or those who do not centralize
their symptoms and recorded their Waddell scores. The patients than
all followed a structured Canadian Back Institute protocol for
active exercise, regardless of centralization status or Waddell
score. A six-month follow up was than conducted on these patients to
determine return to work status. Seventeen patients from the
original sample size were excluded from the results of this study as
their jobs had been terminated or the patients were homemakers,
students or retirees. From this final sample, the researchers
obtained results which revealed that among the patients with low
Waddell scores, those who centralized their symptoms had a higher
return to work rate than those who did not centralize their
symptoms. For those patients that had high Waddell scores, they had
a lower return to work rate, regardless of the patients’ ability to
centralize symptoms. Despite these findings in support of Waddell’s
signs as a predictor for return to work, additional information such
as specifics of patients who had positive Waddell’s signs (ie .
patients who had pain for 14 days or 1 to 2 years, age, gender, type
of occupation) and specifics for the results from the double
straight leg raise they developed would have helped the reader
understand the study better (4). Other shortcomings included the
researchers limiting their approach to movement classification,
having a broad definition of centralization, utilizing multiple
therapists for the study, testing a sagittal plane movement only,
and not having another group to compare results with (4).
However, another study by Bradish et al (5), utilizing Waddell’s
Signs to correlate return to work for 120 worker’s compensation
patients with onset of low back pain within six months displayed
conflicting results compared to Karas et al (3). In this study the
participants underwent a detailed history and physical examination,
examination for nonorganic signs as described by Waddell et al (2)
and a radiographical examination of the lumbosacral spine. The
authors of this study reported treatment for these patients were
symptomatic and at the discretion of the referring practitioners,
with recommendations from the Board as indicated. Between 12-18
months following injury the patients were reviewed again. Analyzing
the initial and review data they found no correlation between the
presence of nonorganic signs at initial assessment and either return
to activity or resolution of the patient’s symptoms. Despite the
study finding no correlation, a few shortcomings of the study could
have resulted in different outcomes. Some of these shortcomings
include the use of multiple therapists, the allowance of varying
treatment procedures and not setting a more specific time parameters
to review the subjects.
Conclusion
Although Waddells’ Signs are a common method to assess the
nonorganic or psychological component of low back pain, great care
must be taken when interpreting results (2, 3, 4). The results
should be viewed as one of many influencing factors, including other
clinical findings and chronicity of the problem (4). Positive
findings should, in fact, alert the therapist to the need for more
detailed testing for the patient (1, 2).
Last revised: October 18, 2010
by Chai Rasavong, MPT, MBA
References
1) Scalzitti DA. Screening For Psycological Factors in Patients with Low
Back Problems: Wadell’s Nonorganic Signs. Physical Therapy. 1997;77:306-312.
2) Waddell G, et al. Nonorganic Physical Signs in Low-Back Pain. Spine.
1980;5(2):117-125.
3) Karas R, et al. The Relationship Between Nonorganic Signs and
Centralization of Symptoms in the Prediction of Return to Work for Patients
with Low Back Pain. Physical Therapy. 1997;77(4):354-360.
4) Erhard R, Scalzitti D, Rothstein J. Conference. Physical Therapy.
1997;77(4):361-368.
5) Bradish C, et al. Do Nonorganic Signs Help to Predict the Return to
Activity of Patients with Low-back Pain? Spine. 1988;13(5):557-560. |
