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Thoracic Outlet Syndrome Shoulder Maneuvers, Plewa, Delinger
337
The False-positive Rate of Thoracic Outlet Syndrome
Shoulder Maneuvers in Healthy Subjects
Michael C. Plewa, MD, Mark Delingel; MD
I
ABSTRACT
.....................................................................................................................................................
Objective: To estimate the incidence of false-positive findings of thoracic outlet syndrome (TOS) shoulder
maneuvers, Adson’s test (AT), costoclavicular maneuver (CCM). elevated arm stress test (EAST), and supraclavicular pressure (SCP) in healthy subjects.
Methods: A cross-sectional, observational study was performed in a medical school and affiliated emergency
medicine residency program setting. Participants included healthy adult volunteers without symptoms of TOS.
The shoulder maneuvers AT, CCM, EAST, and SCP were performed in randomized order for 30 sec, 30 sec,
3 min, and 30 sec, respectively. Pulse quality and the presence and timing of pain or paresthesias were
assessed.
Results: 53 subjects were enrolled, including 27 women, aged 29.7 & 6.4 years (range 21-58 years). AT,
CCM, EAST, and SCP resulted in an altered pulse in 11%. 11%. 62%. and 21%; pain in 0%. 0%, 21%, and
2%; and paresthesias in 11%, 15%, 36%, and 15% of cases, respectively. The following outcomes had reasonable false-positive rates (upper 95% confidence limit): pain with the AT (7%). CCM (7%), SCP (lo%), or
any 2 TOS shoulder maneuvers (10%);discontinuing the EAST because of symptoms (16%);or any symptom
with 3 (13%) or 4 (7%) TOS shoulder maneuvers.
Conclusions: In a study of TOS shoulder maneuvers in healthy subjects, the outcomes of pulse alteration or
paresthesias were unreliable in general. However, TOS shoulder maneuvers have reasonably low false-positive
rates when a positive outcome is defined as pain after AT, CCM, or SCP; discontinuation of the EAST
secondary to pain; pain in the same arm with 2 2 maneuvers; or any symptom in the same arm with 2 3
maneuvers.
Key words: physical examination; thoracic outlet syndrome; pain; paresthesia; perfusion; upper extremity.
Acad. Emerg. Med. 1998; 5:337-342.
I Emergency physicians (EPs) should consider thoracic
outlet syndrome (TOS) in the differential diagnosis during
the evaluation of patients with upper-extremity symptoms
of pain, weakness, numbness, or paresthesias. TOS can
result from compression of the neurovascular bundle by
the first rib, a cervical rib, congenital fibrous bands, or the
anterior scalene muscle.’ There are several variants of
TOS, depending on the site of compression, although all
classically result in pain exacerbated with the arm in the
..........................................................
From Sr. Vincent Mercy Medical Center/The Toledo Hospital Emergency Medicine Residency Program (MCP,MD):and the Medical Colleae
- . of
, Ohio. Toledo. OH. Demrtmeni of
- Suraerv
- . (MCP).
Received: June 3, 1997; revision received: September 30, 1997: accepted: October 5, 1997; updaied: October 31, 1997.
Prior presentation: SAEM annual meeting. Washington,DC, May 1997,
and the 7th Annual Midwest Regional Emergency Medicine Research
Symposium. Akron, OH. April 1997.
Address for correspondence and reprinis: Michael C. Plewa. MD. Si.
Vincent Mercy Medical Cenrec 2213 Cherry Streei, Toledo, OH 43608.
Fax: 419-251-2698; e-mail: mcpiewa@msn.com
elevated position. Vascular forms of TOS are rare, and can
occur following venous compression in 4% of TOS cases,
resulting in upper-extremity swelling, fatigue, venous distention, and cyanosis, or may be due to arterial compression in 1% of TOS cases, resulting in upper-extremity
pallor, coolness, claudication, and eventually ulceration
and gangrene. More than 95% of patients with TOS will
have symptoms related to compression of the brachial
plexus, including numbness, pain, or paresthesias, typically in the ulnar distribution but occasionally radiating to
the chest and neck, and eventual weakness in the hand
grip, triceps, and hand interosseous muscles.
The diagnostic evaluation of TOS should focus on excluding other disorders such as myocardial ischemia, arthritis, fibromyalgia, cervical disk disease, spinal stenosis,
rotator cuff injury, reflex sympathetic dystrophy, multiple
sclerosis, causalgia, carpal tunnel syndrome, Pancoast tumor, and arteritis. Although cervical spine and chest radiographs are recommended,’ evidence supporting their
diagnostic utility is lacking. The rare case of complete
is c o d h n e d by Doppler studies, vevascular
nography, or arteriography. Patients with neurologic find-
338
ACADEMIC EMERGENCY MEDICINE
APR 1998 VOL 5/NO 4
ings such as weakness and muscle atrophy (especially in entrapment disorders such as carpal tunnel and ulnar enthe intrinsic hand muscles) may also have electrophysio- trapment syndrome. The utility of MRI is accepted in exlogic abnormalities on electromyographic, somatosensory cluding cervical disk disease and spinal stenosis, but is
evoked potential, or nerve conduction velocity (NCV) uncertain in the evaluation of neurovascular compression
st~dies.’.~NCV findings classically include low-amplitude in the thoracic ~ u t l e t . ” ~
The diagnostic standard for TOS is controversial.
median motor responses and ulnar sensory action potentials, and normal ulnar motor responses and median sen- Many author^"^" suggest the diagnosis of TOS can be
sory re~ponses”~
and are also useful in excluding nerve made with the following criteria: 1) the presence of typical
I FIGURE 1. Demonstration of the TOS shoulder maneuvers. A. Adson’s rest (AT) involves full inspiration with the neck extended and turned
to either side for 30 seconds. B. For the cosrocluviculur maneuver, both shoulders are pulled downward and backward, in an exaggerated military
position. for 30 seconds. C . The elevated u r n srress test (EAST) involves extension of both shoulders with opening and closing of both fists for
3 minutes. D. Suprucluviculur pressure (SCP)is performed with both thumbs at the lowest portion of the anterior scalene muscle near the first
rib for 30 seconds.
~
Thoracic Outlet Syndrome Shoulder Maneuvers, Plewu, Delinger
upper-extremity symptoms exacerbated by arm elevation,
2) positive findings on TOS shoulder maneuvers, and 3)
the absence of other disorders. Others refute the existence
of neurogenic TOS in the absence of objective physical
(muscle wasting) or electrophysiologic findings, and have
labeled this “disputed” neurogenic TOS.3-8
Regardless of the final diagnosis, it is important for
EPs to be familiar with the various provocative TOS
shoulder maneuvers necessary in the diagnostic evaluation
of this syndrome. Schukla and Carlton’ have noted that
98% of TOS patients were missed during their initial ED
evaluations, in the majority of these instances because
TOS maneuvers were not performed. Several bedside
physical maneuvers have been described to aid in the diagnosis of TOS, including Adson’s test (AT)? the hyperabduction test,” the elevated arm stress test (EAST),” the
costoclavicular maneuver (CCM),” and supraclavicular
pressure (SCP)” (the Methods section and Figure 1 provide further descriptions regarding these techniques).
These TOS shoulder maneuvers have been used with variable test performance
Although several authors state that TOS shoulder maneuvers are unreliable and result in high percentages of
false positives in normal subject^,"-^^ these articles refer
to the AT, hyperabduction test, and CCM, which were
initially defined as positive if there was loss of the radial
pulse. Most a ~ t h o r s ’ * ~ * ’now
’ - ’ ~ suggest
*~~
that positive
TOS maneuvers, especially the EAST and SCP, should
result in reproduction of the patient’s symptoms rather
than pulse alteration. The false-positive rate of TOS maneuvers defined by pain and paresthesias, however, has
been inadequately studied. Our objective was to estimate
the incidence of false-positive findings of TOS shoulder
maneuvers in healthy subjects.
I ...........................................................................
METHODS
Study Design: A cross-sectional, observational study
was performed to estimate the incidence of abnormal TOS
shoulder maneuvers in healthy volunteers. The study was
approved by the Institutional Review Board of the St. Vincent Mercy Medical Center.
Setting and Population: The study was performed in a
medical school and affiliated (EM) residency program setting during November and December 1996. Subjects included healthy adult volunteers who did not have a known
history of previous clavicle, neck, or shoulder fracture,
carpal tunnel syndrome, cervical disk disease, fibromyalgia, reflex sympathetic dystrophy, or symptoms (such as
neck, shoulder or arm pain, or paresthesias) compatible
with TOS.
Interventions and Measurements: The shoulder maneuvers AT, CCM, EAST, and SCP were performed on
~~
339
one arm at a time (except for the EAST, which was with
both arms simultaneously) in each subject in a randomized
order (according to a computer-generated random number
list) for 30 sec, 30 sec, 3 min. and 30 sec, respectively,
with an approximately 60-second rest period between maneuvers. See Figure 1 for details regarding these maneuvers. The hyperabduction test was not studied because this
position is incorporated into the EAST.
Adson’s test (AT) involves sitting in the upright position with shoulders back and hands on the lap, taking a
deep inspiration and extending the neck and the chin toward the affected side.’ This increases the tension of the
anterior and middle scalene muscles, and decreases the
interscalene space. This test has poor sensitivity, being
positive in as few as 2% of patients with TOS.’
For the elevated arm stress test (EAST), both hands
are opened and closed into fists for 3 minutes with both
arms in the hyperabduction position, which closes the costoclavicular space and compresses the neurovascular bundle under the pectoralis minor muscle. A positive EAST,
including reproduction of symptoms of pain and paresthesias in the arm, shoulder, chest, or neck and discontinuation with dropping of the arm for relief of pain, is considered the most reliable test with regard to sensitivity.”
The costocluviculur maneuver (CCM) involves pulling
the shoulders downward and backwards in an exaggerated
military position.” This closes the space between the clavicle and the first rib.
For suprucluviculur pressure (SCP), the observer’s
thumb is pressed in the supraclavicular fossa over the medial scalene muscle for at least 30 seconds.” This indirectly presses on the brachial plexus, and a positive test
results in not only tenderness but reproduction of symptoms in the upper extremity.
The palpated radial pulse quality (present, absent, or
diminished in comparison with previous pulse amplitude)
and the presence, location, and time of onset of pain or
paresthesias were recorded individually by an EM attending and a fourth-year medical student trained in these maneuvers. Measurements were neither repeated in the same
subject (reproducibility) nor repeated with different observers (reliability). Pain was self-reported, but not quantified on a scale, and defined as any discomfort in the
upper extremity, neck, or head on the involved side. Paresthesias were defined as any tingling, burning, “pins and
needles,” or otherwise “funny” sensation. The percentage of positive tests for each maneuver represents the
number of positive tests present in either extremity over
the total number of subjects.
Data Analysis: Data were described with 95% confidence intervals (CIS). A sample size of 50 subjects was
chosen to obtain an estimated precision of 510% if the
percentage of subjects with a negative test is 85% or
higher.
340
ACADEMIC EMERGENCY MEDICINE APR 1998 VOL 5/NO 4
I ..............................................................................
RESULTS
thesias were mild and described as a tingling or "pins and
needles' ' sensation rather than burning or pain.
Fifty-three subjects were enrolled, including 27 women
DISCUSSION
and 26 men, aged 29.7 2 6.4 years (range 21-58 years). I ..............................................................................
The incidence of abnormal TOS shoulder maneuvers is
listed in Table 1. Pulse alterations were observed in some There has been controversy regarding the accuracy of
patients with all maneuvers, but were most common with these shoulder maneuvers in the diagnosis of TOS because
the EAST in comparison with other maneuvers. Paresthe- of varying definitions. When based on findings of a disias were also more common with the EAST, were present minished radial pulse, these maneuvers are thought to be
- ~ pulse alterations may be found in a
only in the upper extremity, and did not radiate into the ~ n r e l i a b l e ' ~since
high
percentage
of asymptomatic individuals. Using phoneck, head, or chest in any case. Pain was absent in cases
toplethysmographic
recordings, Gergoudis and Barnes"
with the AT and CCM maneuvers, and was present in 1
noted
significant
arterial
obstruction (defined as 275% recase with SCP. Although discomfort was more likely with
duction
in
the
digital
pulse
amplitude) in 51%. 14%. and
the EAST, it resulted in discontinuation of the maneuver
9%
of
cases
using
the
Adson's,
costoclavicular, and hyin only 3 (6%; 1- 16%) subjects who dropped the arm at
perabduction
maneuvers,
respectively.
Telford and Mot100 2 17 sec, 2 because of pain and 1 from fatigue. Pulse
tenhead''
noted
diminished
radial
pulses
in approximately
alteration, pain, and paresthesias with at least 1 maneuver
50%
of
healthy
medical
students
with
the
costoclavicular
were present in 74% (60435%). 21% (11-34%) and 47%
al.'"
described reaor
hyperabduction
maneuvers.
Vin
et
(33-61%) of subjects, respectively. although no subject
sonable
specificities
for
the
maneuvers
in
150
normal subhad positive findings with all maneuvers. Table 2 lists the
jects,
with
pulse
obliteration
in
no
subjects
with
the Adoutcomes of altered pulse, pain, or paresthesias into the
son's
test,
and
in
1-17%
with
hyperabduction
between
same extremity with >1 shoulder maneuver.
Pain occurred with the EAST in the shoulder in 1 case, 45" and 180". Warrens and Heatonz3 described false posthe forearm and hand in 6, the hand in 3, and the thumb itives in 58% of cases with at least 1 maneuver, 27% with
in 1. Pain occurred with SCP in the hand and arm in 1 the costoclavicular test, 15% with Adson's test, and 14%
case each. Pain did not follow the classic ulnar distribu- with the hyperabduction test. Wright noted hyperabduction in any case. Pain intensity was described as mild in tion of the arms obliterated the radial pulse in 83% of 150
all cases except for 1 subject, who described pain asso- young, healthy adult volunteer^.'^ Our results are consisciated with EAST as severe. Although subjects were al- tent with these in that the majority of patients (74%) had
lowed to discontinue any TOS shoulder maneuver if nec- alteration in pulse with at least 1 maneuver; however, we
essary because of pain, only 2 individuals discontinued did find that diminished pulse was less common with AT
and CCM than most previous reports. Whereas previous
during the EAST because of pain.
Paresthesias occurred with the AT in the hand and studies have not addressed pulse alterations with EAST
small finger in 1 case each; with the CCM in the forearm and SCP, we found a diminished pulse in the majority of
in 2 cases and the hand in 6; with the EAST in the arm subjects following EAST (62%) and in a significant perin 1 case, the forearm in 4, the forearm and hand in 4, centage of subjects following SCP (21%).
Positive findings on TOS shoulder maneuvers should
the hand in 7, the small finger in 1, the thumb in 1, and
all fingers in 1; with the SCP in the shoulder in 1 case, include reproduction or exacerbation of the patient's
the arm in 2, the forearm in 4, and the hand in 1. Pares- symptoms,'."*2' although several authors criticizing the
thesias were in the ulnar distribution in 5 cases, 3 in the poor specificity of these maneuvers have not commented
forearm and 2 in the small finger. In all cases the pares- on production of pain or paresthesias with these test^.'^'^^'^
The few prior studies to prospectively evaluate the falsepositive rate of TOS maneuvers in healthy subjects with
I ..............................................................................
TABLE 1 Abnormal TOS Shoulder Maneuver Findings*
regard to pain or paresthesias have addressed the hyperabduction maneuver1' and the EAST,= and not the AT,
Maneuver Altered Pulse
Pain
Paresthesias Time (set)? CCM, or SCP. In the study described by Wright,I7 only 2
of 150 normal volunteers noted neurologic symptoms of
AT
11%
0%
11%
21 2 8
(3-1945)
(0-14%)
(3-19%)
pain or paresthesias with shoulder hyperabduction. Novak
0%
CCM
11%
15%
13 2 5
et a1.26found 10 of 300 normal persons developed sensory
(0-14%)
(3-198)
(5-2596)
symptoms within 2-4 minutes after arm elevation.
21%
EAST
62%
36%
89 t 45
In the study by Costigan and W i l b ~ u r n ?the
~ EAST
(49-75%)
(0-32%)
(23-49%)
produced discomfort in 74% of control subjects, although
2%
SCP
21%
15%
18 k 6
(0-32%)
(0-696)
(5-258)
none of these discontinued the maneuver secondary to
pain. Similarly, we found that discontinuing the test be*95% CI in parentheses.
tDenotes average time of onset of altered symptoms.
cause of pain, argued by ROOS'as being essential for a
~~~~
Thoracic Outlet Syndrome Shoulder Maneuvers, Pfewa, Definger
positive test, was quite uncommon (3%), and EAST elicited pain or paresthesias in 21% to 36% of subjects. Also,
since many of our subjects did not develop symptoms
until beyond 90 seconds, it is likely that the specificity of
EAST might be improved by limiting the test to 90 seconds’ duration.
Supraclavicular pressure, described by Roos as one of
the most helpful tests in the diagnosis of TOS,’ has been
the least studied of all the physical maneuvers. Costigan
and Wilbourn” noted supraclavicular tenderness in only
4% of controls and did not describe reproduction of symptoms in any of these healthy volunteers. We also found
the SCP maneuver rarely caused pain, although paresthesias were present in 15%.
Our results suggest that resultant pain may be the most
specific finding during TOS shoulder maneuvers, since
pain was present in no subject during the AT or CCM
tests, and in a single subject during SCP. In general, the
incidence of false-positive findings of pain with the AT,
CCM, and SCP were lower than with EAST and lower
than findings of paresthesias with these maneuvers. Using
the results of several shoulder maneuvers in combination
may also improve the specificity for TOS, since paresthesias or pulse alterations in the same arm with 2 2 tests
were uncommon (1 1%), and pain in the same arm with
2 2 tests was rare (2%).
Although some authors have discounted the TOS maneuvers as being nonspecific, they remain an integral
component of the diagnosis of TOS. For example, Lindgren’ uses a “TOS index” defined as at least 3 of 4 criteria, including history of symptoms aggravated with arm
elevation, paresthesias along the C8-T1 distribution, supraclavicular tenderness over the brachial plexus, and a
positive EAST. Our results suggest that TOS shoulder maneuvers have reasonable specificity when they result in
pain after AT, CCM, or SCP, discontinuation of the EAST
secondary to pain, pain in the same arm with 2 2 maneuvers, or any symptom with 2 3 maneuvers.
Positive TOS maneuvers in the patient with arm pain,
numbness, paresthesias, or weakness aggravated in the elevated position should suggest TOS as a possible diagnosis. Further workup should rule out other causes listed
previously. Since the majority of patients with TOS can
be managed with conservative measures’ such as simple
analgesics, physical therapy, shoulder girdle and cervical
spine mobility exercises, psychosocial intervention, and
avoidance of precipitating factors, most patients can be
managed by their primary care physician with possible
referral to physical medicine and rehabilitation, neurology,
rheumatology, and orthopedic or vascular surgery specialists, as necessary. Rarely, surgical transaxillary first rib
resection“”*’ will be indicated for cases with documented
aneurysm, arterial or venous insufficiency, or true neurologic TOS with muscle weakness and atrophy, or cases
refractory to conservative measures.
I
341
TABLE 2 Abnormal Findings in the Same Arm with a Combination of TOS Shoulder Maneuvers*
..............................................................................
Number of
Maneuvers
W O
Three
Four
Altered Pulse
6% (4-23%)
4% (0-13%)
0%(0-7%)
Pain
Paresthesias
2% (9-10%)
21% (11-34%)
4% 0-13%)
0%(0-7%)
O%(O-7%)
,
0% (0-7%)
*95% CI in parentheses.
I .............................................................................
LIMITATIONS AND FUTURE QUESTIONS
This study has several limitations that deserve discussion.
Because of the small sample size, the confidence intervals
around specificity estimates were wide. There were only
2 observers performing the TOS shoulder maneuvers, and
observations were not repeated on the same subjects;
therefore, the interrater variability could not be determined. The pressure was not measured during the CCM
or SCP maneuvers, but was estimated to be approximately
10 pounds. In addition, we did not measure pain intensity,
such as with a linear analog pain score, although many
subjects described their discomfort as mild. It is possible
that the pain intensities are quite different between subjects with and without TOS.
Since a complete radiographic and electrophysiologic
evaluation of subjects was not performed, it is possible
that positive shoulder maneuvers identified individuals
with asymptomatic carpal tunnel syndrome or cervical
disk disease, or predisposition to TOS in the future.
Several other tests were not evaluated, such as the hyperabduction test, the cervical rotation lateral flexion test,’
Tinel’s sign (tenderness to percussion over the brachial
plexus and supraclavicular fossa),” and the scalene muscle block.” It is possible that any of these could have
better specificity than the 4 TOS shoulder maneuvers studied here.
The most serious study limitation was that our population of normal subjects does not reflect those patients
presenting to the ED with symptoms suggestive of TOS.
We did not address the false-positive rate of TOS shoulder
maneuvers in patients with cervical disk disease, fibromyalgia, reflex sympathetic dystrophy, carpal tunnel syndrome, or other disorders mimicking TOS. In fact, Costigan and Wilbourn’’ have found positive findings with
the SCP and EAST in 23% and 92%. respectively, of patients with carpal tunnel syndrome. We also did not attempt to duplicate the typical 3: 1 female-to-male ratio
found in TOS cases. In addition, this study did not assess
the sensitivities of these TOS shoulder maneuvers in
symptomatic ED patients. In fact, prior studies have infrequently reported the sensitivity of these TOS shoulder
maneuvers because they are usually included in the definition of TOS.
Future study should address the following issues: 1)
342
ACADEMIC EMERGENCY MEDICINE APR 1998 VOL 5/NO 4
the optimal force required for the SCP and CCM maneuvers, 2) the interobserver variability of the various TOS
maneuvers, 3) the utility of chest and cervical radiographic screening in patients with TOS symptoms, and 4)
the optimal TOS shoulder maneuvers with regard to sensitivity and specificity in a prospective evaluation of patients presenting to the ED with symptoms suggestive of
TOS.
I ..............................................................................
CONCLUSION
In a study of TOS shoulder maneuvers in healthy subjects,
which did not address sensitivity, we found outcomes of
pulse alteration or paresthesias to be unreliable in general.
However, TOS shoulder maneuvers have reasonably low
false-positive rates when a positive outcome is defined as
pain after AT, CCM, or SCP; discontinuation of the EAST
secondary to pain; pain in the same arm with 2 2 maneuvers; or any symptom in the same arm with 2 3 maneuvers.
The authors thank Nancy Fenn Buderer. MS, for her statistical assistance and Brooke Thibert for manuscript preparation.
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