Costoclavicular Test – Military Brace

The costoclavicular test is a clinical examination maneuver designed to detect possible compression of neurovascular structures in the costoclavicular space. This assessment is particularly valuable when evaluating patients with suspected thoracic outlet syndrome (TOS), a condition characterized by compression of the brachial plexus and/or subclavian vessels as they pass between the clavicle and the first rib. Medical professionals frequently employ this examination in patients presenting with upper extremity pain, paresthesias, or vascular symptoms that worsen with certain shoulder positions.

How to Perform the Costoclavicular Test?

The costoclavicular test follows a systematic approach that focuses on detecting changes in radial pulse quality and symptom reproduction during specific positioning. To perform this clinical examination properly:

Position the patient in a seated posture with arms hanging naturally at their sides in a relaxed manner. Ensure the patient is comfortable and can maintain this position throughout the examination. The examiner should position themselves where they can access both wrists and observe the patient’s upper extremities simultaneously.

See Also: Adson Test Maneuver

Begin by palpating both radial pulses simultaneously, noting the baseline amplitude, rhythm, and quality. This establishes the patient’s normal pulse characteristics for comparison. Documentation of these initial findings is essential for accurate interpretation of subsequent changes.

Instruct the patient to draw their shoulders downward and backward, creating a military posture with shoulder retraction. Some clinicians refer to this as the “Geisel position” or “military brace position.” The patient should maintain this posture while the examiner reassesses the radial pulses bilaterally.

Compare the pulse quality, amplitude, and any symptomatic changes between the initial relaxed position and the shoulder retraction position. The examiner should document any changes observed, particularly focusing on asymmetry between sides.

Throughout the examination, the clinician should inquire about symptom reproduction, including paresthesias, numbness, or pain that may develop during the maneuver. These subjective reports provide additional diagnostic information beyond the objective pulse changes.

What is the Positive Costoclavicular Test?

A positive costoclavicular test demonstrates specific findings that suggest neurovascular compression in the thoracic outlet region. These findings include:

Diminution or complete obliteration of the radial pulse during the shoulder retraction maneuver represents the primary objective finding. This pulse reduction occurs due to compression of the subclavian artery between the clavicle and first rib when the shoulder is retracted.

Reproduction of the patient’s typical symptoms during the test position provides valuable diagnostic information. These symptoms may include paresthesias along the medial aspect of the arm and hand, pain radiating down the upper extremity, or sensations of heaviness or fatigue in the affected limb.

Asymmetry between sides strongly supports the diagnosis, particularly when pulse changes and symptom reproduction occur unilaterally. While bilateral findings can occur in TOS, unilateral changes that correlate with the patient’s symptomatic side strengthen the diagnostic confidence.

The clinician should note any associated signs such as color changes in the hand, increased pallor, or delayed capillary refill that may accompany the pulse changes. These additional vascular findings further support the diagnosis of vascular compression.

A positive Costoclavicular Test suggests the possibility of thoracic outlet syndrome, specifically costoclavicular syndrome, where compression occurs primarily between the clavicle and first rib rather than at other potential compression sites within the thoracic outlet.

Costoclavicular Test Reliability

The reliability of the costoclavicular test has been evaluated in several clinical studies, revealing important considerations for medical professionals when interpreting results:

Historical studies by Falconer and Weddel identified a significant 60% false-positive rate, indicating that the costoclavicular test may cause temporary neurovascular compression even in individuals without anatomical predisposition to thoracic outlet syndrome. This high false-positive rate necessitates cautious interpretation of positive findings.

Similarly, research by Telford and Mottershead demonstrated radial pulse diminution in approximately 68% of asymptomatic subjects following shoulder retraction. This finding underscores the importance of correlating pulse changes with symptom reproduction rather than relying solely on pulse alterations.

Despite its widespread clinical use, the costoclavicular test lacks robust validation studies establishing its sensitivity and specificity in diagnosing thoracic outlet syndrome. This gap in the literature has led many specialists to recommend using this test as part of a comprehensive clinical examination rather than as a standalone diagnostic procedure.

The test demonstrates better specificity when assessing for vascular forms of TOS compared to neurogenic presentations. Pulse changes provide more objective evidence of vascular compression, whereas symptom reproduction alone may be more subjective and influenced by patient expectations.

Given these reliability limitations, current clinical practice emphasizes the importance of combining multiple provocative maneuvers when evaluating suspected thoracic outlet syndrome. Other complementary tests include Adson’s test, Wright’s test, and the elevated arm stress test (EAST), which may provide additional diagnostic information.

For definitive diagnosis, especially in cases being considered for surgical intervention, clinicians typically supplement clinical examination with imaging studies such as magnetic resonance angiography, computed tomography angiography, or dynamic duplex ultrasound to visualize the anatomical relationships and document neurovascular compression.

The costoclavicular test remains a valuable clinical tool for identifying potential thoracic outlet syndrome, particularly when integrated with a comprehensive history, physical examination, and appropriate diagnostic imaging. Medical professionals should recognize its limitations while appreciating its contribution to the diagnostic process for this challenging clinical condition.

Resources:

• Sanders RJ, Hammond SL, Rao NM. Diagnosis of thoracic outlet syndrome. J Vasc Surg. 2007 Sep;46(3):601-4. doi: 10.1016/j.jvs.2007.04.050. PMID: 17826254. Pubmed
• Hooper TL, Denton J, McGalliard MK, Brismée JM, Sizer PS Jr. Thoracic outlet syndrome: a controversial clinical condition. Part 1: anatomy, and clinical examination/diagnosis. J Man Manip Ther. 2010 Jun;18(2):74-83. doi: 10.1179/106698110X12640740712734. PMID: 21655389; PMCID: PMC3101069. Pubmed
• Laulan J, Fouquet B, Rodaix C, Jauffret P, Roquelaure Y, Descatha A. Thoracic outlet syndrome: definition, aetiological factors, diagnosis, management and occupational impact. Journal of Occupational Rehabilitation. 2011;21(3):366-373. https://link.springer.com/article/10.1007/s10926-010-9278-9
• Povlsen B, Belzberg A, Hansson T, Dorsi M. Treatment for thoracic outlet syndrome. Cochrane Database of Systematic Reviews. 2010;(1):CD007218.