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.     

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.     

Thoracic outlet syndromes

Thoracic outlet syndrome (TOS) is no longer considered to be a single entity. The syndromes are venous (V-TOS), arterial (A-TOS) and neurological (N-TOS), but may co-exist. The end stage of VTOS (Paget Schroetter syndrome or effort thrombosis of the subclavian vein) should be recognized early so that younger sportsmen and musicians in particular can be offered the opportunity of thrombolysis, decompression surgery and balloon venoplasty. Most uncomplicated cases of A-TOS and N-TOS can be treated conservatively with posture, diet, physiotherapy advice and reassurance. Complicated arterial TOS, with aneurysm or embolization, should be treated expeditiously by cervical rib excision and arterial reconstruction. Double crush syndromes are relatively common in patients with TOS. It is easier to treat carpal tunnel syndrome than N-TOS. Muscle wasting and pain are an indication for surgery in N-TOS.     

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     

胸廓出口综合征的诊断治疗进展

胸廓出口综合征(thoracic outlet syndrome,TOS)是指臂丛神经或者锁骨下动脉或者锁骨下静脉在胸廓出口受到卡压而出现的一些列症状。可分为神经型TOS、静脉型TOS和动脉型TOS,其中神经型TOS最为常见。TOS的临床表现非常多样,并且缺乏确诊性的检查方法,因此诊断应结合详细的病史、查体及相关的辅助检查。保守治疗和手术治疗均适用于TOS,并且都能获得较好的预后。神经型TOS首选保守治疗,对于有症状的血管型TOS和保守治疗失败的神经型TOS,应尽早手术。     

Safety and efficacy of the supraclavicular approach to thoracic outlet decompression

BACKGROUND: Thoracic outlet syndrome (TOS) is a clinical diagnosis encountered by both thoracic and vascular surgeons. The goal of surgical therapy involves relieving compression of the neurovascular structures at the superior thoracic aperture. The traditional approach to thoracic outlet decompression has been transaxillary; however more centers are moving toward a more tailored approach through a supraclavicular incision. METHODS: The medical records of 67 patients who underwent surgical decompression between 1993 and 2001 for TOS were retrospectively reviewed. Patient demographics and early outcome were assessed through clinic follow-up. RESULTS: Seventy-two thoracic outlet decompressions were performed on 67 patients with the diagnosis of TOS. Five patients underwent bilateral thoracic outlet decompression. All operations in this time period were safely accomplished through a supraclavicular approach. The syndromes associated with thoracic outlet compression were neurogenic (n = 59), venous (n = 10), and arterial (n = 3). Forty-six of 72 (63.9%) operations resulted in complete resolution of symptoms, 17 cases (23.6%) had partial resolution, and 9 patients (12.5%) had no resolution. There were no deaths and morbidity was minimal with 6 complications (8.3%). CONCLUSIONS: The supraclavicular approach is a safe and effective technique in managing all forms of thoracic outlet compression.     

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.     

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.     

Thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is an often misdiagnosed cause of neck, shoulder, and arm disability. Neurovascular compression may be seen in the interscalene triangle, costoclavicular space, or posterior to the pectoralis minor, although any cause of abnormalities of shoulder girdle alignment may cause a localized area of brachial plexus compression. Nerve compression in this way may lead to upper extremity weakness, pain, paresthesias, and numbness. A careful and detailed medical history and physical examination are essential to proper identification of thoracic outlet syndrome, which remains primarily a clinical diagnosis. Diagnostic testing may differentiate other causes of pain or neurologic symptoms of the upper extremity from TOS. Clinical management is often challenging.     

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.     

Dynamic neuromusculoskeletal ultrasound documentation of brachial plexus/thoracic outlet compression during elevated arm stress testing

Background

The diagnosis and validation of thoracic outlet syndrome/brachial plexopathy (TOS) remains a difficult challenge for surgeons, neurologists, and radiologists. This is due to the fact that the responses of standard elevated arm stress tests can be considered somewhat subjective and can vary. Therefore, non-vascular TOS cases are presently diagnosed clinically, and any objective diagnosis has been controversial.

Methods

This is a technique paper describing the use of dynamic neuromusculoskeletal ultrasound to assist in the diagnosis of thoracic outlet/brachial plexus pathology. We propose a new way to observe the brachial plexus dynamically, so that physical verification of nerve compression between the anterior and middle scalene muscles can be clearly made at the onset of clinical symptoms. This gives a way to objectively identify clinically significant brachial plexus compression.

Results

Dynamic testing can add objective analysis to tests such as the elevated arm stress tests and can correlate the onset of symptoms with plexus compression between the anterior and middle scalene muscles. With this, the area of pathologic compression can be identified and viewed while performing the dynamic testing. If compression is seen and the onset of symptoms ensues, this is a positive confirmatory test for the presence of TOS and a clinically significant disease.

Conclusions

This paper offers a simple, objective, and visual diagnostic test that can validate the presence or absence of brachial plexus compression during arm elevation in patients with brachial plexus injury and thoracic outlet syndrome.     

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.     

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.     

Resection of the first rib, following deep arm vein thrombolysis in patients with thoracic outlet syndrome

In order to evaluate, the prophylactic effect of first rib resection in patients with fibrinolytic recanalised deep arm vein thrombosis, we present our experience with 21 patients. After recanalisation 12 had phlebographic signs of venous compression in the costoclavicular space, with the arm in the normal position. This fulfills the requirements for thoracic outlet syndrome (TOS). In 60 normal persons without symptoms of TOS none had phlebographic signs of venous compression with the arm in normal position. This difference is significant. In the 12 patients TOS was suspected was to be the underlying cause of rethrombosis and first rib resection was performed. Two patients with TOS had rethrombosis before first rib resection could be performed. At follow up 1 to 6 years after the thrombosis no rethrombosis was found. TOS and deep arm vein thrombosis is rare. Controlled studies are not available. We advocate first rib resection in patients with successful fibrinolysis and TOS in order to avoid rethrombosis.     

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.     

Management of thoracic outlet syndrome

The experience with transaxillary first-rib resection and scalenotomy reported herein shows these to be safe and effective treatments for patients with thoracic outlet syndrome (TOS). The former operation usually offers the best possibility for complete resection of the first rib and all anomalous congenital bands, and is curative in most cases, regardless of the mechanism of the compression. Scalenotomy, or Powers' operation, is also helpful, in particular for cases of TOS with a vertebral arterial insufficiency. Accurate diagnosis of TOS and selection for surgery after a detailed history and proper physical examination will result in gratifying relief of symptoms in almost all patients with TOS.     

Management of thoracic outlet syndrome

Summary The experience with transaxillary first-rib resection and scalenotomy reported herein shows these to be safe and effective treatments for patients with thoracic outlet syndrome (TOS). The former operation usually offers the best possibility for complete resection of the first rib and all anomalous congenital bands, and is curative in most cases, regardless of the mechanism of the compression. Scalenotomy, or Powers' operation, is also helpful, in particular for cases of TOS with a vertebral arterial insufficiency. Accurate diagnosis of TOS and selection for surgery after a detailed history and proper physical examination will result in gratifying relief of symptoms in almost all patients with TOS.     

Thoracic outlet syndrome. Thoracic surgery perspective.

We have attempted throughout this review to identify the issues surrounding thoracic outlet syndrome as well as to highlight their origins. It should be clear that many aspects of TOS remain controversial from the definition of the entity through pathogenesis, diagnosis, and treatment. The conflicts surrounding TOS are underlined most poignantly in the many letters to the editor of the New England Journal of Medicine in response to Urschel's 1972 publication. It is incumbent upon those of us who treat patients with TOS to dispel the ignorance surrounding this syndrome with astute, accurate, and reproducible observations. We must clearly define TOS as a clinical entity such that we may analyze the characteristics of the patients we treat. We must continue to search for innovative and specific diagnostic criteria. We must quantitatively and reproducibly measure subjective end points of pain severity and quality of life. The use of these methods will provide yardsticks for therapeutic success and act as determinants for the natural history of TOS. The objectives of treatment will remain the alleviation of symptoms and the restoration of function. We have applied these principles to the formulation of a protocol in which we record, in a prospective manner, both routine and innovative clinical parameters. With quantification of subjective end points, we may be able to correlate clinical presentation with outcome. We also may be able to define with some accuracy this entity we call thoracic outlet syndrome.     

Compression and stretching of the brachial plexus in thoracic outlet syndrome: correlation between neuroradiographic findings and symptoms and signs produced by provocation manoeuvres

In order to investigate the mechanism of nerve irritation in thoracic outlet syndrome (TOS), we studied 150 patients who presented with symptoms of neurologic TOS between 1985 and 1999. They first performed various provocative physical manoeuvres and then underwent injection of contrast medium into the supraclavicular part of the brachial plexus. Several of the provocative manoeuvres were then repeated and radiographs were again obtained. Based on the neuroradiographs, we identified three subsets of patients; those with only compression (type 1 TOS, n=27, 18%), those with combined compression and stretching (type 2 TOS, n=111, 74%), and those with only stretching (type 3 TOS, n=12, 8%). We were able to correlate the neuroradiological subsets with symptoms elicited by pre-radiographic provocative manoeuvres; in 92 patients (61%) these were elicited by traction manoeuvres. We conclude that stretching is an important factor of nerve irritation in TOS.     

Surgical management of thoracic outlet syndrome: a 10-year experience

BACKGROUND: Thoracic Outlet Syndrome (TOS) refers to compression of the neurovascular structures in the region between the scalene muscles and the first rib, or by anatomical abnormalities such as cervical rib, fibrous bands and other variations in the scalene musculature. METHODS: Our experience with 63 consecutive operations for TOS, over a period of 10 years, has been reviewed. Preoperative symptoms and signs, investigations, surgery done, complications and the outcome of surgery are analysed. RESULTS: A total of 60 patients underwent 63 operations for decompression of TOS. All the 63 first ribs, were excised by the transaxillary approach. In seven patients (16%), a combined transaxillary and supraclavicular approach was used. There was no operative mortality in this series. The operative complications included pneumothorax in four patients (6.3%), which was treated by insertion of chest drain, and lower brachial plexus neuropraxia in two patients (3%), which improved with conservative management. The mean duration of postoperative hospital stay was 3.6 days. At 12 months following surgery, 56 patients (93%) had complete or partial relief of symptoms and only four patients (6.6%) had no relief of symptoms. CONCLUSION: The results of the present study confirm that transaxillary excision of the first rib is a surgical procedure associated with very low morbidity and excellent relief of symptoms. It can therefore be offered as an early option for patients with thoracic outlet syndrome. It may be combined with the supraclavicular approach if exposure of the subclavian artery is required for vascular reconstruction.