MedifocusHealth

Part of the challenge of diagnosing thoracic outlet syndrome is distinguishing which symptoms are related to vascular involvement, to neurologic involvement, to both, or to neither and the patient must be tested for all of the above (e.g., arterial TOS is often overlooked if symptoms of neurogenic TOS are prominent). Thoracic outlet syndrome remains a controversial diagnosis and is based entirely on the clinical picture, with attention to:

• Detailed medical history
• Physical examination
• Testing with provocative maneuvers
• Other selective tests

Medical History

A thorough medical history is an essential component of the diagnostic evaluation for thoracic outlet syndrome. Important information to obtain includes:

• What activities initiate symptoms
• Types of symptoms (e.g., numbness, tingling, paresthesia, pain)
• Review of signs and symptoms and description of the pain (exact location, extent, severity, and duration)
• Pattern of pain (e.g., how or if it radiates down the arm)
• Quality of the pain (e.g., shooting pain or aching pain)
• History of previous trauma or injury and extent of injury (e.g., a hand injury which may have indirectly involved the shoulder)
• Progression of symptoms since the injury
• Work history (risk factors for TOS)

Typically, the intensity and frequency of pain and paresthesia increase as the interval of time since the initial injury increases.

Physical Examination

Because the diagnosis of thoracic outlet syndrome is so difficult to pinpoint, the physical examination must focus on all symptoms and not just evaluate symptoms that confirm TOS. Before starting the examination, it is important for the physician to observe the posture of the patient and to notice relevant details such as position of the shoulders (rolled forward, hunched up), and position of the head (forward placement or erect and straight). The focus of the physical exam is on the head, neck, shoulders and arms.

Overall, the following parameters should be evaluated:

• Thorough musculoskeletal and neurologic evaluation
• Evaluation of posture and muscle function in the cervical, thoracic, scapular (upper back muscles) and shoulder areas
• Passive range of motion of the neck, shoulder, elbow, wrist
• Evaluation of reflexes (biceps and triceps muscles)
• Manual muscle strength test
• Sensory response to light touch and warm/cold stimuli
• Vascular examination to detect acute or chronic blood flow problems (arterial insufficiency; venous thrombosis)

Arms

• Check for blood pressure differences between the two arms. A difference greater than 20 mm Hg is significant and may be indicative of involvement of the subclavian artery.
• Compare both arms and hands for temperature, color, edema, skin moisture, nail growth, and other physical characteristics.
• Evaluate and compare muscle strength in muscle groups of each arm. Strong biceps and weak triceps may be indicative of TOS.

• Test for carpal tunnel syndrome (CTS) by looking at the Tinel sign and Phalen's test.

  • Tinel sign - a test to detect nerve irritation. The target nerve is lightly tapped (percussed) to elicit a sensation of pins and needles (tingling) in the path of the nerve distribution. This test is positive in carpal tunnel syndrome but not in TOS.

  • Phalen's maneuver - the patient keeps their wrist flexed to the maximum for 30 seconds which compresses the carpal tunnel. If the test is positive for CTS, the patient experiences burning and tingling in the fingers, but not for TOS.

Head and Neck