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Thoracic Outlet Syndrome

Thoracic outlet syndrome: neurogenic vs vascular, first rib resection (corpus-synthesised).

56 citationsUpdated Sep 2026
Illustration: Thoracic Outlet Syndrome

For patients: a plain-language version of this topic is available. See the patient guide.

Overview

Thoracic outlet syndrome is a specific, treatable compressive neurovascular disorder characterized by distinct symptoms, often attributed to congenital abnormalities, anatomic deformity, or trauma [2]. It is a complex condition that may present as neck and arm pain, yet remains difficult to diagnose due to the lack of established consensus in diagnostic criteria [4, 6]. While most patients achieve success with conservative treatment, which serves as the general first-line therapy, the condition can be challenging and frustrating to manage [4, 10]. Arterial thoracic outlet syndrome is rare but potentially devastating when diagnosis is overlooked or delayed [8].

Surgical intervention is reserved for patients who fail conservative therapy [4]. Specifically, surgical decompression of the thoracic outlet is indicated for compliant patients who fail nonsurgical management and respond favorably to targeted injections [20]. Failure to make the correct diagnosis or to appreciate the presence of a significant shoulder problem or additional peripheral nerve problems is a major concern in treatment [9]. Persistence of complaints in the upper extremity after adequate decompression at the thoracic outlet indicates that additional distal compression should be attempted [12].

Surgeons must maintain vigilance for iatrogenic thoracic outlet syndrome during clavicle fracture fixation, particularly when multiple subacute failures occur [26]. In such cases, a low threshold for diagnostic testing like venography is required if signs of iatrogenic thoracic outlet syndrome develop [26]. Additionally, nonunion of a first rib fracture may lead to thoracic outlet syndrome that is unresponsive to conservative treatment, necessitating resection of the first rib [23].

Anatomy & Pathophysiology

Classification and Etiology

Thoracic outlet syndrome is a compressive neurovascular disorder with multiple causes and symptoms, often attributed to congenital abnormalities, anatomic deformity, or trauma [2]. The condition results from compression of the neurovascular structures that pass through the thoracic outlet [51]. The two basic types of thoracic outlet syndrome are vascular and neurogenic [13]. The vascular type is further divided into arterial and venous subtypes [13]. The neurogenic type has been subdivided into “true” and “disputed” neurogenic categories, a distinction attributed to Wilbourn [13]. Patients with arterial, venous, and electrically positive neurogenic thoracic outlet syndrome present with an obvious mechanical obstruction to blood flow or have positive electrodiagnostic tests [13]. The fourth subtype, disputed neurogenic thoracic outlet syndrome, accounts for up to 97% of all those diagnosed and treated for the condition [13]. The term "electrically negative neurogenic TOS" is proposed to replace the nomenclature "disputed neurogenic" [13].

Arterial Thoracic Outlet Syndrome: Arterial thoracic outlet syndrome is uncommon, accounting for only 1% to 2% of all cases [13, 67]. Symptoms related to arterial involvement are rare, being less than 1% of all forms of the condition [68]. There is almost always an osseous anomaly such as a cervical rib, an anomalous first rib, or a history of fracture in arterial thoracic outlet syndrome [13, 67]. It is unlikely to have a case of arterial thoracic outlet syndrome without a bony anomaly [67]. Clavicle nonunion, malunion, posttraumatic subluxation of the sternoclavicular joint, and rib fractures have been identified as causes [67]. The subclavian artery can become stenotic or develop an aneurysm because of compression between the rib and the clavicle or because of traction over the cervical rib [67]. The subclavian artery can ulcerate, become occluded, or become thrombotic [67]. Arterial thoracic outlet syndrome results from obstruction of the subclavian artery with claudication, thrombus formation, and possible embolization [51]. It may present as a limb-threatening condition [13, 67].

Venous and Neurogenic Thoracic Outlet Syndrome: Venous thoracic outlet syndrome, also known as Paget-Schroetter Syndrome, involves subclavian-axillary venous occlusion, thrombus formation, and rare embolization [51]. Neurogenic thoracic outlet syndrome presents with upper-extremity symptoms attributable to compression of the brachial plexus [51]. Symptoms related to thoracic outlet syndrome are mostly neurological, accounting for more than 90% of cases [68].

Pathophysiology and Mechanisms

Thoracic outlet syndrome typically develops as a nerve entrapment syndrome under pathophysiological mechanisms, including a combination of anatomical predisposition and extraneous factors [19]. The predisposing anatomy at the thoracic outlet region is common [19]. Extraneous factors leading to decompensation include acquired factors, neck trauma, and shoulder trauma [19]. The brachial plexus is susceptible to injury by traction, compression, or hemorrhage following neck or shoulder trauma [19]. Brachial plexus traction injuries are most often after the extension or acute flexion of the neck [19]. These traction injuries are responsible for the development of thoracic outlet syndrome in some patients [19].

Throwing Mechanics and Scapular Kinematics: Repetitive throwing motion can increase the stiffness of the middle scalene muscle, potentially leading to compression of the brachial plexus and/or subclavian artery [42]. Abduction and external rotation of the shoulder in a simulated throwing position showed high elastic moduli of the anterior and middle scalene muscles [65]. No significant differences in elastic moduli of the anterior and middle scalene muscles were observed when adding neck rotation toward the nonthrowing side [65]. Adaptive scapulothoracic changes leading to scapular asymmetry have been described in the asymptomatic thrower [60]. Changes in static and dynamic scapular mechanics arise from overuse and weakness of the scapular stabilizers and posterior rotator cuff muscles [60]. With the arm hanging at the side, the throwing shoulder’s scapula has increased upward rotation (abduction), internal rotation (protraction), antetilting in the sagittal plane, and inferior translation [60]. During forward arm elevation, the scapula upwardly and internally rotates and retracts [60]. Scapular upward rotation has been theorized to be a key adaptation to the cocking phase of throwing [60]. Altered scapular positioning, although initially asymptomatic, can predispose the shoulder to injury [60]. The lower placement of the shoulder girdle relative to the upper thorax was related to neurogenic thoracic outlet syndrome [53]. A loss of throwing arm external rotation appears to be the main factor behind shoulder range of motion changes in the neurogenic thoracic outlet syndrome group [78].

Anatomical Variations and Measurements

There was no difference between the characteristics of the interscalene triangle or the costoclavicular space between the right and left sides [37]. There was no difference between the characteristics of the interscalene triangle or the costoclavicular space between males and females [37]. The mean distance of the neurovascular bundle from the posterior border of the clavicle was found to be 9.2 mm [68]. Recognition of dorsal scapular nerve anatomy and pathology may provide a more comprehensive understanding of scapular dysfunction in patients with thoracic outlet syndrome [86].

Classification

Neurogenic, Venous, and Arterial Subtypes: Thoracic outlet syndrome is classified into neurogenic, venous, or arterial categories [51]. Patients with arterial, venous, and electrically positive neurogenic thoracic outlet syndrome rarely present with secondary concerns such as workers’ compensation issues or litigation that cloud the clinical picture [13]. Diagnosis for these subtypes is straightforward via physical examination, routine diagnostic imaging, or testing [13]. Surgical treatment for these specific subtypes is relatively successful when indicated [13]. Adjunct diagnostic studies frequently confirm the diagnoses of venous and arterial thoracic outlet syndrome, but not of neurogenic thoracic outlet syndrome [51]. In arterial thoracic outlet syndrome, the subclavian artery can become stenotic or develop an aneurysm because of compression [13].

Electrically Negative Neurogenic Thoracic Outlet Syndrome: The fourth subtype, historically termed disputed neurogenic thoracic outlet syndrome, has been more difficult for some physicians to accept [13]. This classification was first described in 1984 [13]. It is recommended to drop the nomenclature of disputed neurogenic thoracic outlet syndrome and adopt the term electrically negative neurogenic thoracic outlet syndrome [13]. Patients with electrically negative neurogenic thoracic outlet syndrome account for up to 97% of all those diagnosed and treated for thoracic outlet syndrome [13]. This entity is only disputed for clinicians who require findings on objective diagnostic studies or imaging for verification of clinical findings [13]. There have been no definitive studies by which one can make the diagnosis of electrically negative neurogenic thoracic outlet syndrome [13].

Other Considerations: Thoracic outlet syndrome is a controversial condition involving compression of neurovascular structures by fibromuscular and fibro-osseous tissues, often leading to misdiagnosis [17]. The term thoracic outlet syndrome was first used by Peet in 1956 [73]. It was defined as neurovascular symptoms of the upper extremity presumably caused by mechanical changes with narrowing of the spaces in the thoracic outlet through which the major nerves and vessels pass [73]. Other names for this condition include scalenus anticus syndrome, costoclavicular syndrome, cervical rib syndrome, subcoracoid-pectoralis minor syndrome, and first-thoracic rib syndrome [73]. Clinicians tend to call the compression site the thoracic outlet because the structures being compressed are exiting the chest in this location [73]. Anatomists consider the term thoracic outlet incorrect and refer to the same area as the thoracic inlet [73].

Clinical Presentation

Thoracic outlet syndrome (TOS) is a complex condition characterized by varied manifestations and a lack of confirmatory testing, making it a difficult diagnosis [24]. It serves as an umbrella term for compressive pathologies in the supraclavicular and infraclavicular fossae, with the vast majority of cases being neurogenic in nature [44]. Clinicians must include TOS in the differential diagnosis for patients presenting with upper extremity signs and symptoms that are not referable to more common conditions, as it may be a primary cause of neck and arm pain [6, 24]. The diagnostic complexity of TOS always requires complementary tests [55].

Classification and Subtypes

TOS is fundamentally divided into vascular and neurogenic types [13]. The vascular type is further subdivided into arterial and venous subtypes, while the neurogenic type is categorized into “true” and “disputed” neurogenic TOS [13]. Patients with arterial, venous, and electrically positive neurogenic TOS present with obvious mechanical obstruction to blood flow or positive electrodiagnostic tests [13]. Diagnosis by physical examination, routine diagnostic imaging, or testing is straightforward for these subtypes, which rarely involve secondary concerns such as workers’ compensation issues or litigation that cloud the clinical picture [13].

Arterial TOS is uncommon, accounting for only 1% to 2% of all TOS cases [13]. It is almost always associated with an osseous anomaly, such as a cervical rib, an anomalous first rib, or a history of fracture [13]. This subtype may present as a limb-threatening condition, where the subclavian artery can become stenotic or develop an aneurysm due to compression [13].

The fourth subtype, historically termed “disputed neurogenic” TOS, has been more difficult for some physicians to accept [13]. Patients with this subtype account for up to 97% of all those diagnosed and treated for TOS [13]. It is recommended to drop the nomenclature "disputed neurogenic" and adopt the term electrically negative neurogenic TOS [13].

Clinical Symptoms and Signs

In neurogenic thoracic outlet syndrome, pain is present in 99% of patients [34]. Symptoms are exacerbated by elevation in 97% of cases [34]. Tenderness to palpation of the scalene triangle or subcoracoid space is present in 96% of patients [34]. Numbness, paraesthesia, or weakness in the arm and/or hand is present in 94% of patients [34]. A positive Elevated Arm Stress Test (EAST) is present in 94% of patients [34].

TOS should be considered in the differential diagnosis for overhead athletes, particularly those presenting with pain, paresthesia, and functional disability in the upper limb [58]. Exercise-enhanced anterior scalene muscle/pectoralis minor muscle blocks can facilitate the clinical diagnosis of neurogenic TOS in high-performance overhead athletes with 'dead arm' symptoms [35]. Repetitive overhead activity, particularly when combined with scapular dyskinesia, leads to pectoralis minor shortening, decreased volume of the retropectoralis minor space, and subsequent brachial plexus compression causing neurogenic TOS [44].

Diagnostic Challenges and Criteria

While consensus in diagnostic criteria has not yet been established, general first-line therapy is conservative treatment, with surgery considered for patients who fail conservative therapy [4]. The Society of Vascular Surgeons (SVS) Clinical Diagnostic Criteria (CDC) or the Consortium of Research and Education on Thoracic Outlet Syndrome (CORE-TOS) CDC are commonly quoted for diagnosing neurogenic TOS [34]. Future studies evaluating the diagnostic accuracy of MRI and/or MRN in TOS must be prospective, include an objective reference standard to minimize bias, and adopt concrete diagnostic criteria for patient inclusion and operative indications [11].

Specific historical and anatomical factors are present in a subset of neurogenic TOS patients. A history of previous clavicle/first rib fracture or the presence of a cervical rib is found in 8% of patients [34]. Previous cervical or peripheral nerve surgery is present in 20% of patients [34]. Anatomical variations such as muscle fusion or nerve piercing the muscle are common in the Japanese population, which may have implications for TOS diagnosis and management [41]. The scalene triangle base width in the Japanese population (8.2 mm) is narrower than in Western populations [41]. There was no difference between the characteristics of the interscalene triangle or the costoclavicular space between the right and left sides or between males and females [37].

Surgeons must be vigilant in considering iatrogenic TOS during clavicle fracture fixation, especially with multiple subacute failures, and should have a low threshold for diagnostic testing like venography if signs develop [26]. Malunion of the first rib can cause TOS [36]. Traumatic events in previously asymptomatic individuals with congenital synostoses of the first and second ribs can lead to combined arterial and neurogenic TOS [29]. Congenital pseudarthrosis of the clavicle can also cause TOS [15].

TOS typically develops as a nerve entrapment syndrome under pathophysiological mechanisms involving a combination of anatomical predisposition and extraneous factors [19]. Extraneous factors leading to decompensation include acquired factors, neck trauma, and shoulder trauma [19].

Investigations

Clinical Assessment: Thoracic outlet syndrome is a complex condition that is difficult to diagnose and must be considered as a potential cause of neck and arm pain [6]. Failure to establish the correct diagnosis or to identify significant shoulder pathology and additional peripheral nerve problems represents a major concern in patient management [9]. While consensus on diagnostic criteria has not yet been established, general first-line therapy is conservative treatment, with surgery reserved for patients who fail conservative management [4]. The "disputed" neurogenic subtype accounts for up to 97% of all patients diagnosed and treated for the condition [13]. In contrast, patients with arterial, venous, and electrically positive neurogenic thoracic outlet syndrome present with obvious mechanical obstruction to blood flow or positive electrodiagnostic tests, making diagnosis by physical examination, routine diagnostic imaging, or testing straightforward [13].

MRI: MRI should be used in combination with clinical assessment and other investigations for thoracic outlet syndrome [76]. Future studies evaluating the diagnostic accuracy of MRI and/or MRN must be prospective, include an objective reference standard to minimize bias, and adopt concrete diagnostic criteria for patient inclusion and operative indications [11].

CT: Multidetector CT and three-dimensional reconstructions hold promise for refining the understanding of anatomic anomalies associated with thoracic outlet syndrome [27]. Measurements of the thoracic outlet region from CT images are significantly similar to cadaveric measurements, suggesting CT measurements may be used to evaluate the region in patients with thoracic outlet syndrome [74].

Ultrasound: Duplex scanning did not help make the diagnosis of neurogenic thoracic outlet syndrome despite a highly significant association between symptomatic upper limbs and vascular compression [84]. Dynamic neuromusculoskeletal ultrasound documentation 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 [25].

Other Considerations: The use of dynamic imaging of the shoulder helped identify the aetiology of painful shoulder clunking in a patient with thoracic outlet syndrome after no diagnosis was determined using conventional imaging [52].

Treatment

Non-Operative

The mainstay of treatment for thoracic outlet syndrome is nonsurgical management, which includes education, activity modification, and physical therapy [24]. Initial nonoperative treatment for neurogenic thoracic outlet syndrome includes pectoralis minor stretching, as well as periscapular and postural retraining [44]. Nonoperative treatment is successful in the majority of patients with neurogenic thoracic outlet syndrome [44]. For recurrent symptoms, management should start with conservative treatment similar to primary TOS, including physical therapy modalities, medications (muscle relaxants, analgesic soothing creams, and liniments), trigger point injections, and job requirement modifications [49]. Rehabilitation for overhead athletes emphasizes restoring full shoulder mobility, motor control, and normalized scapular mechanics, as well as improving functional thoracic range of motion [61]. Neuromuscular electrical stimulation and targeted muscle exercises are incorporated into this rehabilitation process [61]. A collegiate-level throwing athlete returned to full participation at her previous level of play within 18 weeks of rehabilitation initiation for neurogenic thoracic outlet syndrome [61].

Operative

Indications: Surgery is considered for patients with thoracic outlet syndrome who fail conservative therapy [4]. For recalcitrant cases, surgical intervention may be considered [24]. In cases of vascular thoracic outlet syndrome, surgery should be considered more promptly because of the underlying potential of limb- or life-threatening complications [24]. Surgical decompression of the thoracic outlet is reserved for patients who fail nonsurgical management and respond favorably to targeted injections [20].

Surgical Approach / Technique: A direct, 3-step approach for the decompression of common sites of brachial plexus entrapment in patients with neurogenic thoracic outlet syndrome has been described [16]. Pectoralis minor tenotomy is utilized in the surgical management of neurogenic thoracic outlet syndrome [21]. Surgical release of the pectoralis minor may be performed through a variety of approaches for patients who fail nonoperative management [44]. Both open and arthroscopic pectoralis minor release may be performed safely with effective resolution of neurogenic symptoms [44]. When further indicated by the preoperative workup, pectoralis minor release can be combined with suprascapular nerve release [44]. By modifying the technique with a scalenotomy, the range of indications for endoscopic treatment of neurogenic thoracic outlet syndrome can be extended [33]. The treatment of venous thoracic outlet syndrome addresses three problems: the clot, the extrinsic compression, and the intrinsic damage to the vein [38].

Revision: The primary surgical procedures used for thoracic outlet syndrome generally are considered difficult, demanding, and high-risk whether the procedure used is first rib resection, scalenectomy, or a combined approach [49]. The surgical procedures that are available for recurrent thoracic outlet syndrome are even more difficult, more demanding, and riskier than the primary operations [49]. Patients with recurrent thoracic outlet syndrome most likely will require a combined approach to get the best possible result by reoperation [49]. Recurrent thoracic outlet syndrome patients should be treated mainly with a transaxillary procedure that involves the removal of the remaining posterior portion of the first rib (if it is more than 1 cm) with external neurolysis of the lower brachial plexus, vasolysis of the subclavian artery and vein, and possible removal of most of the second rib especially if it is highly positioned [49].

Other Considerations: Nonunion of a first rib fracture may lead to thoracic outlet syndrome that is unresponsive to conservative treatment, and resection of the first rib may be necessary [23]. Corrective clavicular osteotomy and plate fixation can effectively alleviate persistent symptoms of thoracic outlet syndrome caused by clavicular malunion [46]. Operative management successfully treated the patient's symptoms of thoracic outlet syndrome caused by congenital pseudarthrosis of the clavicle [15]. Overall, patients did well long-term after decompression of the thoracic outlet in adolescent patients [14]. There was no difference in return to play based on the type of thoracic outlet syndrome in professional baseball players [28].

Postoperative Care

Postoperative care protocols exist for patients who had thoracic outlet release with scalenectomy and neurolysis [32].

Complications

Arterial and Vascular Complications

The evidence provided does not specify incidence rates, risk factors, or management protocols for arterial or vascular complications in this context.

Iatrogenic and Post-Traumatic Complications

Iatrogenic: Possible transformation or straightening of the natural curvature of the clavicle may cause neurovascular thoracic outlet syndrome [31]. Post-Traumatic: Neck trauma and shoulder trauma are extraneous factors that can lead to thoracic outlet syndrome development [19].

Diagnostic and Management Challenges

Primary Surgery: The primary surgical procedures used for thoracic outlet syndrome are generally considered difficult, demanding, and high-risk [49]. Recurrent Disease: Surgical procedures available for recurrent thoracic outlet syndrome are even more difficult, more demanding, and riskier than the primary operations [49].

Recovery

Postoperative Care: Protocols for patients undergoing thoracic outlet release with scalenectomy and neurolysis have been described [32].

Long-term Outcomes: Patients generally did well long-term after decompression of the thoracic outlet in adolescent populations [14]. In professional baseball players, surgery for thoracic outlet syndrome can help prolong a career and help pitchers maintain their performance over time similar to peers who have not had surgery for TOS [39].

Neurologic Sequelae: Symptoms of neurologic sequelae after interscalene brachial plexus block resolved spontaneously with a median duration of 4 weeks, except in cases of motor weakness or clinical brachial plexopathy which required therapeutic interventions [75].

Key Evidence

  • [L5] Thoracic outlet syndrome is a compressive neurovascular disorder with multiple causes and symptoms, often attributed to congenital abnormalities, anatomic deformity, or trauma. [2] (10.1016/s0749-0712(21)00359-0)
  • [L5] This article aims to review the epidemiology, etiology, relevant anatomy, clinical presentations, diagnosis, and management of thoracic outlet syndrome, noting that while consensus in diagnostic criteria has not yet been established, general first-line therapy is conservative treatment and surgery is considered for patients who fail conservative therapy. [4] (10.3390/jcm10050962)
  • [L5] Diagnosing and treating thoracic outlet syndrome can be challenging and frustrating. [5] (10.1016/s0749-0712(03)00080-5)
  • [L4] Thoracic outlet syndrome is a complex disease hard to be diagnosed that should be taken into consideration as it may be a reason of neck and arm pain. [6] (10.4172/2167-0846.1000173)
  • [L5] Thoracic outlet syndrome (TOS) is a specific disease with specific symptoms that is treatable. [7] (10.1016/s0749-0712(03)00087-8)
  • [L5] Arterial thoracic outlet syndrome is rare but can be devastating when the diagnosis is overlooked or delayed. [8] (10.1016/s0749-0712(03)00086-6)
  • [L5] The author emphasizes that failure to make the correct diagnosis or to appreciate the presence of a significant shoulder problem or additional peripheral nerve problems is a major concern in treatment of patients with thoracic outlet syndrome. [9] (10.1016/s0749-0712(03)00084-2)
  • [L5] Most patients with thoracic outlet syndrome are successful with conservative treatment unless there is significant neural loss or vascular compression. [10] (10.1016/s0749-0712(03)00081-7)
  • [L5] Future studies evaluating diagnostic accuracy of MRI and/or MRN in thoracic outlet syndrome must be prospective, include an objective reference standard to minimize bias, and adopt concrete diagnostic criteria for patient inclusion and operative indications. [11] (10.1016/j.otsr.2020.05.001)
  • [L4] Persistence of complaints in the upper extremity after adequate decompression at the thoracic outlet is an indication that additional distal compression should be attempted. [12] (10.1007/bf00571487)
  • [L4] Overall, patients did well long-term after decompression of the thoracic outlet. [14] (10.1177/2325967119s00378)
  • [L5] Operative management successfully treated the patient's symptoms of thoracic outlet syndrome caused by congenital pseudarthrosis of the clavicle. [15] (10.1136/bcr-2013-010437)
  • [L5] The aim of this Technical Note is to describe a direct, 3-step approach for the decompression of common sites of brachial plexus entrapment in patients with neurogenic thoracic outlet syndrome. [16] (10.1016/j.eats.2023.07.019)
  • [L5] Thoracic outlet syndrome is a controversial condition involving compression of neurovascular structures by fibromuscular and fibro-osseous tissues, often leading to misdiagnosis. [17] (10.1016/s0749-0712(03)00114-8)
  • [L4] [19] (10.3390/jcm12216811)
  • [L5] Surgical decompression of the thoracic outlet is reserved for compliant patients who fail nonsurgical management and respond favorably to targeted injections. [20] (10.1016/j.jhsg.2022.07.004)
  • [L4] The study elucidates the utilization and long-term effectiveness of pectoralis minor tenotomy (PMT) in patients with neurogenic thoracic outlet syndrome (NTOS). [21] (10.1177/15589447241286240)
  • [Case_report] Nonunion of a first rib fracture may lead to thoracic outlet syndrome that is unresponsive to conservative treatment, and resection of the first rib may be necessary. [23] (10.1016/j.jse.2010.03.011)
  • [L5] [24] (10.5435/00124635-199411000-00003)
  • [L4] 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. [25] (10.1007/s11552-013-9523-8)
  • [Case_report] Surgeons must be vigilant in considering iatrogenic thoracic outlet syndrome during clavicle fracture fixation, especially with multiple subacute failures, and should have a low threshold for diagnostic testing like venography if signs develop. [26] (10.1016/j.jse.2009.05.014)
  • [L4] The technique holds promise for refining the understanding of anatomic anomalies associated with thoracic outlet syndrome. [27] (10.1016/s0749-0712(03)00115-x)
  • [L3] There was no difference in return to play based on the type of thoracic outlet syndrome. [28] (10.1177/03635465241243244)
  • [L4] Traumatic events in previously asymptomatic individuals with congenital synostoses of the first and second ribs can lead to combined arterial and neurogenic thoracic outlet syndrome. [29] (10.1016/j.jhsa.2014.08.034)
  • [L4] Possible transformation or straightening of the natural curvature of the clavicle may cause neurovascular thoracic outlet syndrome. [31] (10.1016/j.jse.2015.12.014)
  • [L5] This article presents the authors' postoperative care protocol for patients who had thoracic outlet release with scalenectomy and neurolysis. [32] (10.1016/s0749-0712(03)00091-x)
  • [L5] By modifying the technique with a scalenotomy, the range of indications for endoscopic treatment of neurogenic thoracic outlet syndrome can be extended. [33] (10.1016/j.eats.2024.103237)
  • [L4] [34] (10.1177/17589983251411877)
  • [L4] Exercise-enhanced ASM/PMM blocks can facilitate the clinical diagnosis of neurogenic thoracic outlet syndrome in high-performance overhead athletes with 'dead arm' symptoms. [35] (10.1177/0363546516665801)
  • [L4] This is the first report of a malunion of the first rib causing thoracic outlet syndrome in the English literature. [36] (10.1007/s00402-007-0355-2)
  • [L5] There was no difference between the characteristics of the interscalene triangle or the costoclavicular space between the right and left sides or between males and females. [37] (10.1016/j.jmpt.2012.04.017)
  • [L5] The treatment of venous thoracic outlet syndrome addresses three problems: the clot, the extrinsic compression, and the intrinsic damage to the vein. [38] (10.1016/s0749-0712(03)00094-5)
  • [L3] Surgery for thoracic outlet syndrome can help prolong a professional baseball players career and help pitchers maintain their performance over time similar to their peers who have not had surgery for TOS. [39] (10.1177/2325967121s00680)
  • [L4] The scalene triangle base width in the Japanese population (8.2 mm) is narrower than in Western populations, and anatomical variations such as muscle fusion or nerve piercing the muscle are common, which may have implications for thoracic outlet syndrome diagnosis and management. [41] (10.1186/s12891-025-09048-2)
  • [L4] Repetitive throwing motion can increase the stiffness of the middle scalene muscle, potentially leading to compression of the brachial plexus and/or subclavian artery. [42] (10.1177/2325967120s00402)
  • [L5] [44] (10.1016/j.xrrt.2022.05.008)
  • [L4] Corrective clavicular osteotomy and plate fixation can effectively alleviate persistent symptoms of thoracic outlet syndrome caused by clavicular malunion. [46] (10.2106/00004623-200203000-00016)
  • [L4] [49] (10.1016/s0749-0712(03)00085-4)
  • [L4] [51] (10.1249/jsr.0b013e3181b8556d)
  • [L4] After no diagnosis was determined using conventional imaging, the use of dynamic imaging of the shoulder helped to identify the aetiology of painful shoulder clunking in our patient. [52] (10.1177/1758573214533781)
  • [L4] The lower placement of the shoulder girdle relative to the upper thorax was related to NTOS. [53] (10.1016/j.jhsa.2012.02.022)
  • [L5] The complexity of TOS's diagnosis always requires complementary tests. [55] (10.1016/j.otsr.2020.03.008)
  • [L5] TOS should be taken into account in the differential diagnosis in overhead athletes, especially in those cases presenting with pain, paresthesia, and functional disability in the upper limb. [58] (10.1097/jsm.0000000000000329)
  • [L5] [61] (10.1016/j.asmr.2021.11.007)
  • [L4] Abduction and external rotation of the shoulder in a simulated throwing position showed high elastic moduli of the anterior and middle scalene muscles, while no significant differences were observed when adding neck rotation toward the nonthrowing side. [65] (10.1177/23259671221114930)
  • [L5] [68] (10.1016/s0020-1383(15)30035-8)
  • [L5] [73] (10.1016/s0749-0712(03)00112-4)
  • [L4] Since measurements from CT images and cadavers were significantly similar, CT measurements may be used to evaluate the thoracic outlet region in patients with TOS. [74] (10.1093/icvts/ivy129)
  • [L2] Symptoms resolved spontaneously with a median duration of 4 weeks, except in cases of motor weakness or clinical brachial plexopathy which required therapeutic interventions. [75] (10.1213/01.ane.0000148696.11814.9f)
  • [L4] MRI should be used in combination with clinical assessment and other investigations. [76] (10.1016/j.otsr.2019.09.020)
  • [L3] A loss of throwing arm ER appears to be the main factor behind shoulder ROM changes in the nTOS group. [78] (10.1177/23259671211000764)
  • [L3] Despite a highly significant association between symptomatic upper-limbs and vascular compression, duplex scanning did not help make the diagnosis of NTOS. [84] (10.3390/diagnostics11010126)
  • [L5] The authors conclude that recognition of dorsal scapular nerve anatomy and pathology may provide a more comprehensive understanding of scapular dysfunction in these patients. [86] (10.1016/j.jhsa.2026.04.017)

See Also

References

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[13] Thoracic Outlet Syndrome. 2021.

[14] Surgical Decompression for Thoracic Outlet Syndrome in Adolescent Patients. Orthopaedic Journal of Sports Medicine. 2019. DOI: 10.1177/2325967119s00378

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[16] Three‐Step Approach for the Decompression of Brachial Plexus Entrapment in Patients With Neurogenic Thoracic Outlet Syndrome. Arthroscopy Techniques. 2023. DOI: 10.1016/j.eats.2023.07.019

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[20] Modern Treatment of Neurogenic Thoracic Outlet Syndrome: Pathoanatomy, Diagnosis, and Arthroscopic Surgical Technique. Journal of Hand Surgery Global Online. 2023. DOI: 10.1016/j.jhsg.2022.07.004

[21] Utilization and Effectiveness of Pectoralis Minor Tenotomy in the Surgical Management of Neurogenic Thoracic Outlet Syndrome. HAND. 2024. DOI: 10.1177/15589447241286240

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