Fmoc-Argininol(Tos)

Thoracic outlet syndrome (TOS) is a nonspecific label. When employing it, one should define the type of TOS as arterial TOS, venous TOS, or neurogenic TOS. Each type has different symptoms and physical findings by which the three types can easily be identified. Neurogenic TOS (NTOS) is by far the most common, comprising well over 90% of all TOS patients. Arterial TOS is the least common accounting for no more than 1%. Many patients are erroneously diagnosed as "vascular" TOS, a nonspecific misnomer, whereas they really have NTOS. The Adson Test of noting a radial pulse deficit in provocative positions has been shown to be of no clinical value and should not be relied upon to make the diagnosis of any of the three types. The test is normal in most patients with NTOS and at the same time can be positive in many control volunteers. Arterial TOS is caused by emboli arising from subclavian artery stenosis or aneurysms. Symptoms are those of arterial ischemia and x-rays almost always disclose a cervical rib or anomalous first rib. Venous TOS presents with arm swelling, cyanosis, and pain due to subclavian vein obstruction, with or without thrombosis. Neurogenic TOS is due to brachial plexus compression usually from scarred scalene muscles secondary to neck trauma, whiplash injuries being the most common. Symptoms include extremity paresthesia, pain, and weakness as well as neck pain and occipital headache. Physical exam is most important and includes several provocative maneuvers including neck rotation and head tilting, which elicit symptoms in the contralateral extremity; the upper limb tension test, which is comparable to straight leg raising; and abducting the arms to 90 degrees in external rotation, which usually brings on symptoms within 60 seconds.

Thoracic outlet syndrome (TOS) is a rare condition (1-3 per 100,000) caused by neurovascular compression at the thoracic outlet and presents with arm pain and swelling, arm fatigue, paresthesias, weakness, and discoloration of the hand. TOS can be classified as neurogenic, arterial, or venous based on the compressed structure(s). Patients develop TOS secondary to congenital abnormalities such as cervical ribs or fibrous bands originating from a cervical rib leading to an objectively verifiable form of TOS. However, the diagnosis of TOS is often made in the presence of symptoms with physical examination findings (disputed TOS). TOS is not a diagnosis of exclusion, and there should be evidence for a physical anomaly that can be corrected. In patients with an identifiable narrowing of the thoracic outlet and/or symptoms with a high probability of thoracic outlet neurovascular compression, diagnosis of TOS can be established through history, a physical examination maneuvers, and imaging. Neck trauma or repeated work stress can cause scalene muscle scaring or dislodging of a congenital cervical rib that can compress the brachial plexus. Nonsurgical treatment includes anti-inflammatory medication, weight loss, physical therapy/strengthening exercises, and botulinum toxin injections. The most common surgical treatments include brachial plexus decompression, neurolysis, and scalenotomy with or without first rib resection. Patients undergoing surgical treatment for TOS should be seen postoperatively to begin passive/assisted mobilization of the shoulder. By 8 weeks postoperatively, patients can begin resistance strength training. Surgical treatment complications include injury to the subclavian vessels potentially leading to exsanguination and death, brachial plexus injury, hemothorax, and pneumothorax. In this review, we outline the diagnostic tests and treatment options for TOS to better guide clinicians in recognizing and treating vascular TOS and objectively verifiable forms of neurogenic TOS.

Introduction Thoracic outlet syndrome (TOS) is one of the most extensively discussed diagnoses. There is neither a clear and homogenous clinical presentation nor an accepted definition. The term describes a complex of symptoms and complaints caused by the compression of nerves and vascular structures at one of the three defined constrictions of the upper thoracic aperture. Methods Based on a comprehensive literature review, this article presents the etiology, epidemiology and clinical diagnostics as well as the possibilities and outcomes of surgical treatment. Results The thoracic outlet syndrome is currently subdivided into three main forms: vascular TOS (vasTOS) including arterial TOS (aTOS) and venous TOS (vTOS), neurogenic TOS (nTOS), which is further subdivided into typical (nTOS) and atypical TOS (disTOS), and a mixed form of nTOS and vasTOS (nvasTOS). The diagnosis is complex and difficult since the disTOS group comprises over 90 % of all patients. In addition to conservative treatment attempts, nTOS may be treated by surgical procedures focusing on the decompression of neurovascular structures. A significant improvement after surgery was found in up to 92 % of cases. The most common access sites are supraclavicular and transaxillary. 50 to 80 % of patients benefit from surgery in the long run. The rates of vascular or neurological complications reported by specialised centres are 0 to 2 %; minor complications such as pneumothorax, bleeding and lymphatic fistula are reported in up to 25 % of cases. Summary Most patients suffering from any form of TOS benefit from surgical treatment. Duration of symptoms, socioeconomic factors and, most notably, stringent diagnostic workup and an adequate operative procedure performed by an experienced centre are crucial to success.