胸廓出口综合征的新认识——解剖学与临床观察

目的探讨胸廓出口综合征的病因。方法对３０具６０侧经福尔马林固定的成人尸体小斜角肌及前中斜角肌的起始部进行解剖研究;对５３例胸廓出口综合征手术患者（１９６６～１９９４年４５例,１９９６～１９９７年８例）随访情况进行总结分析。结果解剖研究发现小斜角肌的出现率为８８３％,Ｔ１神经根或其下干在小斜角肌近段起源的腱性组织上跨过;前中斜角肌在颈椎横突的前后结节均有起点,Ｃ５、Ｃ６神经根从前中斜角肌的交叉腱性起点中穿过。４５例１９６６～１９９６年手术者中,有颈肩痛症状者３４例,术后１７例颈肩痛症状仍存在,其中７例加重;８例１９９６～１９９７年手术者中,７例有颈肩痛,术中切断前中斜角肌在Ｃ５～６神经根旁的腱性纤维组织,术后仅有１例仍有颈肩部不适。结论小斜角肌的腱性纤维是臂丛神经下干或Ｔ１神经根受压的原因;前中斜角肌在Ｃ４～５横突前后结节的交叉腱性起点是压迫Ｃ５～６,有时包括Ｃ７神经根或臂丛神经上（中）干的原因     

Thoracic outlet and pectoralis minor syndromes

Compression of the neurovascular bundle to the upper extremity can occur above or below the clavicle; thoracic outlet syndrome (TOS) is above the clavicle and pectoralis minor syndrome is below. More than 90% of cases involve the brachial plexus, 5% involve venous obstruction, and 1% are associate with arterial obstruction. The clinical presentation, including symptoms, physical examination, pathology, etiology, and treatment differences among neurogenic, venous, and arterial TOS syndromes. This review details the diagnostic testing required to differentiate among the associated conditions and recommends appropriate medical or surgical treatment for each compression syndrome. The long-term outcomes of patients with TOS and pectoralis minor syndrome also vary and depend on duration of symptoms before initiation of physical therapy and surgical intervention. Overall, it can be expected that >80% of patients with these compression syndromes can experience functional improvement of their upper extremity; higher for arterial and venous TOS than for neurogenic compression.     

Thoracic outlet syndrome

Thoracic outlet syndrome (TOS) consists of a group of distinct pathologies arising as a result of compression of structures at the thoracic outlet. The structures at risk are, from anterior to posterior, the subclavian vein, subclavian artery and brachial plexus. Compression or impingement causes venous (VTOS), arterial (ATOS) or neurogenic (NTOS) TOS. NTOS is the most common presentation, caused by compression of the brachial plexus at the scalene triangle or pectoralis minor space. Other compression syndromes at the carpal and cubital tunnels should be excluded. Management is usually conservative, employing physiotherapy and postural exercises, but pain or muscle wasting may be indications for surgery. VTOS is caused by compression of the subclavian vein at the costoclavicular junction, resulting in venous thrombosis, the Paget-Schroetter syndrome, often as a result of exercise in fit young muscular people or musicians. Positional swelling of the upper limb without thrombosis is termed McCleery's syndrome. In the presence of thrombosis, clot lysis, first rib excision and venoplasty may be indicated. ATOS occurs due to compression of the subclavian artery at the scalene triangle, often in association with an anomalous bony structure, such as cervical rib, causing post-stenotic aneurysmal dilation of the artery, thrombosis and embolization. Acute upper limb ischaemia necessitates urgent cervical rib excision and arterial reconstruction.     

Thoracic-outlet-Syndrom

The thoracic outlet syndrome (TOS) is a disputed syndrome in the field of the so-called compression syndromes of the upper extremity. This is no surprise, as the TOS is a complex and multifactorial compression syndrome diagnosed by different medical specialities. On average 6.5 physicians of different specialities need 4.3 years to come up with the diagnosis of TOS. The correct diagnosis is of great importance and crucial for successful operative treatment. The necessary diagnostic tests can only be accomplished by team work, especially interdisciplinary cooperation. This expressly includes physiotherapy and not just the medical disciplines. This contribution presents a summary of the approaches and interactions involved in effective diagnosis and treatment of TOS.     

胸廓出口综合征非手术和手术治疗的长期随访

目的 了解胸廓出口综合征的解剖学基础，分析颈神经根受压的临床特点、诊断和治疗。方法 对1995—1999年间的18例胸廓出口综合征患者作平均6．9年的随访，其中8例作手术治疗，10例作非手术治疗（局部封闭为主）。胸廓出口综合征的特点是颈神经根在椎间孔外受压，以颈肩痛、手麻痛为主要表现，可伴有上肢的酸痛及功能障碍。结果 治疗后颈肩痛消失或明显缓解，并有较大的功能改善。非手术治疗和手术治疗的疗效分别为60％和75％。结论 胸廓出口综合征的非手术治疗和手术治疗均有效，并都有一定的反复，需长期反复治疗，应严格掌握手术指征。     

Diagnosis of thoracic outlet syndrome

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.     

Diagnosis and treatment of thoracic outlet syndrome

TOS represents a spectrum of disorders encompassing four related syndromes: arterial compression, venous compression, neurogenic compression, and a poorly defined pain syndrome. Patients can present with signs of arterial insufficiency, venous obstruction, painless wasting of intrinsic hand muscles, and pain. History and physical examination are the most important diagnostic studies, and radiographs of the chest and cervical spine and electromyography/nerve conduction studies are useful to identify other causes of pain and disability. Surgical intervention is indicated for patients failing nonoperative maneuvers and can usually yield satisfactory results. TOS may also be the most underrated, overlooked, and misdiagnosed, and the most important and difficult to manage peripheral nerve compression in the upper extremity.     

Treatment of Thoracic Outlet Syndrome: Long-term Results

Thoracic outlet syndrome (TOS) refers to a complex of symptoms in the upper extremity caused by compression of the neural and vascular structures at some point between the interscalene triangle and the inferior border of the axilla. A review of our experience in treating this controversial syndrome is presented. Between 1989 and 1997 a series of 23 patients (5 men, 18 women) were operated on for TOS. The average age of the patients was 26.4 years (range 17–60 years). All patients complained of pain typically in the shoulder and proximal upper extremity with radiation to the neck, and most had paresthesias and numbness in the forearm and hand. Their symptoms had been present for 8 months to 9 years (mean 2.6 years). All were evaluated by history, physical examination, radiographs of the chest and cervical spine, electromyography, and nerve conduction studies; computed tomography, magnetic resonance imaging, angiography, and myelography were conducted selectively. When TOS was suspected, a cooperative concept was utilized employing the aid of the neurologist, orthopedist, and occasionally a cardiologist. The initial treatment was physical therapy for a minimum of 6 weeks. If no relief occurred they underwent surgery. In all patients in the present series the first rib was removed through a transaxillary approach. A cervical rib was also removed in four cases. Postoperatively, they were evaluated by questionnaire and reexamination. Nineteen (82.6%) had complete relief, and four had partial relief of symptoms. Complications included pneumothorax and temporary brachial paralysis in one case each. We concluded that careful selection of patients for surgery can yield satisfactory results, and a coordinated team of thoracic surgeons, neurologists, and physical therapists is important for management of these patients.     

First rib resection in thoracic outlet syndrome

Most patients with thoracic outlet syndrome (TOS) present with exercise-induced upper extremity paresthesia. Neurogenic TOS is the most common type where the brachial nerve plexus is compressed against a tight thoracic outlet. Vascular compromise although rare can result from thoracic outlet pressure against the subclavian artery or more commonly the subclavian vein. This article reviews the pathophysiology of TOS and describes several effective surgical interventions. Complete first rib resection with surgical decompression is an essential part of the treatment for TOS. First rib resection via supraclavicular or a preferred transaxillary route should be considered when conservative modalities provide no symptom improvement.     

Thoracic outlet syndrome

Thoracic Outlet Syndromes (TOS) consists of a group of distinct pathologies arising from compression or impingement of structures at the thoracic outlet. The structures at risk are, from anterior to posterior, subclavian vein (venous — VTOS), subclavian artery (arterial — ATOS) and brachial plexus (neurogenic — NTOS). NTOS is the most common presentation, usually caused by compression of the brachial plexus at the scalene triangle or pectoralis minor space. Neurogenic compression syndromes at the carpal and cubital tunnels should be excluded. Management of NTOS is usually conservative, employing physiotherapy and postural exercises, but pain or muscle wasting may be indications for surgery. VTOS is caused by compression of the subclavian vein at the costoclavicular junction, resulting in venous thrombosis (Paget—Schroetter syndrome) often as a result of exercise in fit young muscular people or musicians. Positional swelling of the upper limb without thrombosis is termed McCleery's syndrome. In acute thrombosis, clot lysis, first rib excision and venoplasty may be indicated. ATOS occurs due to compression of the subclavian artery at the scalene triangle, often in association with an anomalous bony structure, such as cervical rib, causing post-stenotic aneurysmal dilation of the artery, thrombosis and distal embolization. Acute upper limb ischaemia necessitates urgent cervical rib excision and arterial reconstruction.     

Reoperation for thoracic outlet syndrome

The clinical history and operative findings in a group of 60 patients who underwent reoperation for thoracic outlet syndrome (TOS) are presented. The patients were severely disabled by arm, shoulder, and neck pain and presented with physical findings pointing to scar fixation of the brachial plexus in the neck (upper tract recurrence) or at the thoracic outlet (lower tract recurrence). The causes of recurrence of TOS as discovered at operation are outlined. Basic principles governing the surgical management of recurrent TOS are elimination of the known causes of recurrence, thorough neurolysis of the brachial plexus, and coverage of the nerves with healthy fat. The role of an expanded PTFE surgical membrane (Gortex) as an adjunct to prevent recurrent scarring is discussed. The surgeon who operates on patients with recurrent TOS must be capable of managing the potential intraoperative complications of severe nerve injury and life threatening bleeding.     

History of thoracic outlet syndrome

Thoracic outlet syndrome (TOS), a condition in which neurovascular structures in the thoracic outlet region are compressed, can be caused by anatomical abnormalities or acquired changes in the soft tissues and bony structures in the region. The brachial plexus is the most frequently affected structure. TOS is one of the most difficult neurovascular compressions in the upper extremity to manage because of the variability of complaints and the high risk associated with surgical treatment.     

Complete cervical rib. Possible neurovascular implications of the upper limb

The thoracic outlet syndrome (TOS) is caused by compression of the brachial plexus or subclavian artery or vein in the region of the neck and shoulder girdle. The neurovascular bundle may be compressed at multiple sites: costoclavicular space, interscalene triangle, insertion of the pectoralis minor into the coracoid process. More than 90% of the patients present with neurologic symptoms: pain, paraesthesias or arm and hand weakness and 10% also have vascular problems. The diagnosis of TOS is always difficult and depends on careful clinical study of patients. For the neurological type of TOS, electromyograms, arteriograms and venograms are not helpful. The value of Doppler study and of arteriography is demonstrated in the present case of a woman with a five month history of pain and paraesthesias of the arm and hand, who shoved sudden occlusion of left humeral artery. Roentgenograms showed the presence of a well developed left cervical rib. Doppler study and arteriography showed the compression of subclavian artery with the arm abduction manoeuver. After first rib resection and humeral artery thrombectomy there was a complete return of humeral artery flow and of all neurologic functions. Thus the role of first cervical rib or other bone and muscular structures must be emphasyzed both in the brachial and in the subclavian artery or vein compression. Embolization of the axillary or humeral artery should be corrected as soon as possible when the cervical rib is corrected.     

Subclavian vein obstruction without thrombosis

BACKGROUND: Unilateral arm swelling caused by subclavian vein obstruction without thrombosis is an uncommon form of venous thoracic outlet syndrome (TOS). In 87 patients with venous TOS, only 21 patients had no thrombosis. We describe the diagnosis and treatment of these patients. MATERIAL AND METHODS: Twenty-one patients with arm swelling, cyanosis, and venograms demonstrating partial subclavian vein obstruction were treated with transaxillary first rib resection and venolysis. RESULTS: Eighteen (86%) of 21 patients had good-to-excellent improvement of symptoms. There were two failures (9%). CONCLUSIONS: Unilateral arm swelling without thrombosis, when not caused by lymphatic obstruction, may be due to subclavian vein compression at the costoclavicular ligament because of compression either by that ligament or the subclavius tendon most often because of congenital close proximity of the vein to the ligament. Arm symptoms of neurogenic TOS, pain, and paresthesia often accompany venous TOS while neck pain and headache, other common symptoms of neurogenic TOS, are infrequent. Diagnosis was made by dynamic venography. First rib resection, which included the anterior portion of rib and cartilage plus division of the costoclavicular ligament and subclavius tendon, proved to be effective treatment.     

胸廓出口综合症——术前手内在肌肌力与术后恢复的关系

研究TOS(Thoracic Outlet Syndrome)患者患肢的术前肌力与术后各症状恢复情况,以把握最佳手术时机。随访40例TOS45侧肢体,术前手内肌肌力≥3级者38侧,肌力<3级者7侧。比较两组患肢手内肌肌力下降、手部及前臂尺侧麻木、颈肩部不适及肢体发冷发白等症状在术后的恢复情况。结果,肌力≥3级者术后肌力及感觉恢复明显优于肌力<3级者,颈肩部不适与肢体发冷发白的症状,两组相比无明显差异。结论认为TOS应早期手术松解臂丛神经血管,尤其对肌力下降者更应如此,以防止病变产生不可逆性变化。手术效果不佳者中,患肢发冷发白者可能与交感神经功能失调有关,颈肩部不适者可能合并有颈椎病。     

Thoracic outlet compression syndrome

In patients suffering from chronic, therapy-resistant shoulder and arm pains, the thoracic outlet compression syndrome (TOS) should be included in the differential diagnosis. It is very important to look out for neurogenic disorders as well as early signs of vascular compression in order to prevent ischaemic injuries. Although the initial complaints appear slight and can in some cases be treated successfully by conservative methods, neurogenic disorders due to TOS as well as arterial and venous manifestations of the syndrome should be treated by resection of the first rib. Only in this way can irreversible neurogenic lesions and arterial or venous complications be prevented.     

Role of anterior scalene muscle hypertrophy in thoracic outlet syndrome

A case of hypertrophic anterior scalene muscle surgically treated is reported. The patient suffered from upper limb intermittent claudication at any sustained upper extremity activity such as lifting a weight or opening and closing the hand with the arm abducted. Doppler and angiographic study showed significant compression of subclavian artery with hyperabduction and Adson manoeuver. Simple anterior scalenotomy was followed by prompt recovery of symptoms. The results of scalenotomy and other surgical approaches to thoracic outlet syndrome are reviewed in the literature. The most common anomalies of anterior scalene muscle in the TOS are also described. Doppler and arteriographic study in different functional positions are necessary in the evaluation of subclavian artery compression by osseous or muscular structures. In the reported case scalenotomy was at least as effective as 1st rib resection.     

Anomalous vasculature as direct cause of upper brachial plexus thoracic outlet syndrome

Direct vascular etiologies of upper plexus thoracic outlet syndrome (TOS) other than the subclavian vessels are exceptional. This is a unique case of an anomalous artery and its accompanying vein causing direct compression to the upper brachial plexus causing TOS. All symptoms resolved after successful treatment consisting of ligation and resection of the vessels. This case demonstrates that although direct vascular etiologies causing upper plexus TOS are extremely uncommon, they should be considered in the differential diagnosis.     

Diagnosis and treatment of thoracic outlet syndrome

Patients who develop symptoms of thoracic outlet syndrome (TOS) have a predisposing anatomic abnormality. In most patients with TOS, the symptoms are caused by entrapment of the brachial plexus and they do not arise from compression of the subclavian artery, as was previously thought. The tests advocated for diagnosing this common syndrome (i.e., evaluating the positional compression of the artery when the arms are raised, the neck is turned, or the shoulders are braced) cannot accurately diagnose this syndrome. There are two reasons for this. The symptoms of TOS are not related to the compression of the artery in the outlet in 98% of patients, and 75% of normal individuals without symptoms show diminished radial pulse on various provocation tests. We employed four timed provocation tests (minute tests) to diagnose TOS: the timed Morley test, timed Wright test, timed Eden test, and elevated arm stress exercise, all of which are very sensitive. In normal individuals without symptoms, 20% experience transitional symptoms such as slight pain and tiredness, on these tests indicating a subclinical state. TOS is treated by keeping the thoracic outlet wide, this being done either conservatively or surgically. In 1993 and 1994, we conservatively treated 418 of 422 patients with TOS by means of active exercise, a brace, and by block therapy. These measures did not reduce the symptoms in 23 of these patients, so surgical treatment was indicated. In the remaining 4 of the 422 patients, conservative treatment was not indicated and surgery was performed directly. All the patients showed significant clinical improvement of varying degree. Presented at the 69th Annual Meeting of the Japanese Orthopaedic Association, Tokyo, April 12, 1996