Adson Test for Diagnosing Thoracic Outlet Syndrome

Adson Test is used to evaluate the presence of Thoracic Outlet Syndrome which is a compression syndrome at the base of the neck with compromised neurovascular function. It was was first described by Adson and Coffey in 1927 as a method to assess for circulatory disruption due to a cervical rib.

How do you perform the Adson Test?

• The patient is positioned in sitting with the arms placed at 30 degrees of abduction.
• The clinician palpates the radial pulse.
• The patient is asked to inhale deeply, and to hold his or her breath.
• The patient is then asked to tilt the head back (extension), and rotate the head, so that the chin is elevated and pointed towards the examined side.
• The examiner evaluates the quality of the radial pulse in this position and compares it with the quality of the pulse with the arm resting at the patient’s side

See Also: Wright Test

What does a positive Adson Test mean?

Diminution or disappearance of the pulse in the test position (positive Adson Test) indicates that the vascular component of the neurovascular bundle is being compressed within either the interscalene triangle or the costoclavicular triangle.

Reproduction of paresthesias with this maneuver can also occur, indicating compression of a neural structure. However, in 1951, Adson suggested that subclavian artery compression can also indicate compression and/or microtrauma of neural elements even in the absence of paresthesias.

Adson Maneuver Reliability

Adson’s test has been reported to have:

• Sensitivity: 79 – 94 %
• Specificity: 74- 100 %

Plewa and Delinger found the specificity of this test to be 100% when assessing pain, 89% when assessing vascular changes, and 89% when assessing paresthesia.

Several other authors have suggested that a positive Adson test result may be associated with worse outcomes after either surgery or rehabilitation, especially in those with mixed neural and vascular symptoms. Clearly, it is important to consider the entire clinical picture before making the diagnosis of TOS using any physical examination maneuver. This includes a combination of the history, other physical findings and, potentially, imaging studies that serve to improve diagnostic accuracy.

Other TOS Test

Other tests for Thoracic Outlet Syndrome include:

Costoclavicular Test:

The patient sits with the arms hanging relaxed. The examiner palpates the wrists to take the pulse in both radial arteries, noting amplitude and pulse rate. Then the patient abducts and externally rotates both arms and retracts the shoulders (Geisel position). With the patient in this position, the examiner again palpates the wrists and evaluates the pulse in both radial arteries.

Unilateral weakness or absence of the radial pulse, ischemic skin changes, and paresthesia are clear signs of compression of the brachial plexus and the axillary artery and vein in the costoclavicular region between the first rib and clavicle (costobrachial syndrome; droopy shoulder syndrome).

Falconer and Weddel found a 60 % false positive rate indicating that this maneuver may cause compression even in the absence of predisposing anatomy. Similarly, Telford and Mottershead found radial pulse diminution in 68 % of normal subjects after shoulder retraction. Although this technique has been used extensively, there have been no studies that have evaluated its actual sensitivity or specificity in the diagnosis of TOS.

Allen Maneuver:

The patient sits or stands. The examiner stands behind the patient and flexes the patient’s elbow to 90° while the shoulder is abducted horizontally and placed into external rotation. The patient then rotates the head away from the test side.

The examiner palpates the radial pulse, which disappears when the head is rotated. This disappearance indicates a positive test result for thoracic outlet syndrome, which may be caused by clavicular fractures with excessive callus or residual displacement of fragments, a cervical rib, a bifid clavicle, or abnormalities of the scalenus medius muscle.

Halstead Maneuver

Dr. William Halstead was the first to identify and treat lesions of the subclavian artery due to the presence of cervical ribs in the late 1910s. The “Halstead maneuver” was developed to induce compression of the subclavian vessels and/or the brachial plexus within the costoclavicular space; however, the test is also purported to identify compression within the interscalene triangle and may be a useful adjunct to Adson test.

The Halstead maneuver is performed with the patient sitting on the examination table with the arms in a neutral position. The patient is then asked to extend the neck while the examiner simultaneously palpates the radial pulse at the wrist.

A positive test occurs when the pulse amplitude decreases as the neck is extended and may indicate compression within either the interscalene triangle or the costoclavicular space. The examiner can also apply gentle traction to the arm to help elicit symptoms. An MRI study by Demirbag et al. found that the Halstead maneuver produced a significantly decreased distance between neurovascular structures and the inferior border of the clavicle within the costoclavicular space.

Although this test has been widely referenced in the literature, there have been no clinical studies that have evaluated the validity or reliability of the test for diagnosing TOS.

Wright Test:

The Wright Test was discussed Here: Wright Test

Roos Test

The Roos Test was discussed Here: Roos Test

Notes:

• The test is significant for identifying neurovascular compression of the subclavian artery and brachial plexus of the ipsilateral side, which is commonly caused by hypertrophy of the scalenus anterior muscle, the presence of a rudimentary cervical rib or a significantly widened transverse process of the seventh cervical vertebra with a fibrous band running from the process to the first rib.
• A positive Adson test suggests a scalenus anticus syndrome, also called cervical rib syndrome, Adson’s syndrome, or Naziger’s syndrome.

References

1. Adson AW. Cervical ribs: symptoms, differential diagnosis, and indications for section of the insertion of the scalenus anticus muscle. J Int Coll Surg. 1951;16(5):546–59.
2. Rayan GM, Jensen C. Thoracic outlet syndrome: provocative examination maneuvers in a typical population. J Shoulder Elbow Surg. 1995;4(2):113–7.
3. Gillard J, Pérez-Cousin M, Hachulla E, Remy J, Hurtevent JF, Vinckier L, Thévenon A, Duquesnoy B. Diagnosis thoracic outlet syndrome: contribution of provocative tests, ultrasonography, electrophysiology, and helical computed tomography in 48 patients. Joint Bone Spine. 2001;68(5):416–24.
4. Marx RG, Bombardier C, Wright JG. What we know about the reliability and validity of physical examination tests used to examine the upper extremity. J Hand Surg. 1999;24A(1):185–92.
5. Nord KM, Kapoor P, Fisher J, Thomas AG, Sundaram A, Scott K, Kothari MJ. False positive rate of thoracic outlet syndrome diagnostic maneuvers. Electromyogr Clin Neurophysiol. 2008;48(2):67–74.
6. Plewa MC, Delinger M. The false-positive rate of thoracic outlet syndrome shoulder maneuvers in healthy subjects. Acad Emerg Med. 1998;5(4): 337–42.Nichols AW. The thoracic outlet syndrome in athletes. J Am Board Fam Pract. 1996 Sep-Oct;9(5):346-55. PMID: 8884673.
7. Demirbag D, Unlu E, Ozdemir F, Genchellac H, Temizoz O, Ozdemir H, Demir MK. The relationship between magnetic resonance imaging findings and postural maneuver and physical examination tests in patients with thoracic outlet syndrome: results of a double-blind, controlled study. Arch Phys Med Rehabil. 2007;88(7):844–51.
8. Plewa MC, Delinger M. The false-positive rate of thoracic outlet syndrome shoulder maneuvers in healthy subjects. Acad Emerg Med. 1998 Apr;5(4):337-42. doi: 10.1111/j.1553-2712.1998.tb02716.x. PMID: 9562199.
9. Falconer MA, Weddel G. Costoclavicular compression of the subclavian artery and vein. Lancet. 1943;2:539.
10. Telford ED, Mottershead S. Pressure of the cervicobrachial junction; an operative and anatomical study. J Bone Joint Surg (Br). 1948;30B(2):249–65.
11. Clinical Tests for the Musculoskeletal System 3rd Edition.
12. Dutton’s Orthopaedic Examination, Evaluation, And Intervention 3rd Edition.