A 53-year-old woman presented with severe right upper extremity rest pain. She reported a history of bilateral Raynaud phenomenon with cold exposure for many years. She also had progressively worsening right second- and third-digit pallor and pain on arm elevation for 1 year. Physical examination revealed a pale right hand (Figure 14-1A and B) with tender digits, absent radial and ulnar pulses, weakly palpable brachial pulse, and associated hand-grip weakness. No abnormalities were noted on her left upper extremity vascular or neurologic examination.

She had undergone thromboembolectomy and patch angioplasty of the right brachial artery with a normal upper extremity arteriogram 4 months prior for treatment of brachial artery occlusion. She had a negative rheumatology and thrombophilia evaluation at that time, and after initial improvement her symptoms recurred a month later. She underwent a brachioradial bypass, again with temporary resolution of her symptoms.

The patient sought a second opinion and noninvasive vascular studies revealed the absence of right digital laser Doppler signals at baseline and after warming (Figure 14-2). Upper extremity computed tomographic arteriogram (CTA) (Figure 14-3) revealed occlusion of subclavian artery with abduction. Upper extremity arteriogram confirmed occlusion of the mid brachial artery with multiple emboli noted in circumflex humeral and collateral arteries (Figure 14-4A and B; Figure 14-5A and B). The distal radial artery was reconstituted via collaterals through the interosseous artery to provide flow into the palmar arch (Figure 14-5B).

The patient was treated with cervical rib resection, subclavian artery resection and replacement, and brachiointerosseus arterial bypass and was doing well 6 months after the procedure.

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  Arterial symptoms are present in a minority of patients, encompassing up to 5% of all thoracic outline syndrome (TOS) patients.¹

  
  
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  TOS is believed to be the most common cause of acute upper extremity arterial occlusion in adults younger than 40 years; it is more common with occupations or activities that involve prolonged posturing of the neck. However, there is no increased incidence in athletes.²

  
  
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  Although strong female preponderance is seen in TOS, arterial TOS affects both genders equally.³

  
  
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  There is a wide variation in age at diagnosis between the second and eighth decades, with a peak in the fourth decade. Younger patients have a greater likelihood of anatomic or structural abnormality (Figure 14-6A).²