Thoracic outlet syndrome: a controversial clinical condition. Part 1: anatomy, and clinical examination/diagnosis

Troy L. Hooper1, Jeff Denton2, Michael K. McGalliard1,3, Jean-Michel Brisme´e1,3, Phillip S. Sizer Jr1,3

1Center for Rehabilitation Research, School of Allied Health Sciences, Texas Tech University Health Science Center, 2Outpatient Physical Therapy Services, Northwest Texas Hospital System, 3Department of Rehabilitation Sciences, School of Allied Health Sciences, Texas Tech University Health Sciences Center, USA

Thoracic outlet syndrome (TOS) is a frequently overlooked peripheral nerve compression or tension event that creates difficulties for the clinician regarding diagnosis and management. Investigators have categorized this condition as vascular versus neurogenic, where vascular TOS can be subcategorized as either arterial or venous and neurogenic TOS can subcategorized as either true or disputed. The thoracic outlet anatomical container presents with several key regional components, each capable of compromising the neurovascular structures coursing within. Bony and soft tissue abnormalities, along with mechanical dysfunctions, may contribute to neurovascular compromise. Diagnosing TOS can be challenging because the symptoms vary greatly amongst patients with the disorder, thus lending to other conditions including a double crush syndrome. A careful history and thorough clinical examination are the most important components in establishing the diagnosis of TOS. Specific clinical tests, whose accuracy has been documented, can be used to support a clinical diagnosis, especially when a cluster of positive tests are witnessed.

Keywords: Diagnosis, Examination, Literature review, Thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is a frequently or venous and neurogenic TOS can subcategorized as overlooked peripheral nerve compression that creates either true or disputed. Furthermore, the term TOS difficulties for the clinician regarding diagnosis and fails to identify the compressing insult or mechanism, management.1 The term ‘thoracic outlet syndrome’ thus prompting individuals to propose an alternative was originally coined in 1956 by Peet to indicate nomenclature that identifies the anatomical factors compression of the neurovascular structures in the involved.6 interscalene triangle corresponding to the possible The disagreement regarding the definition of TOS etiology of the symptoms.2–4 Since Peet provided this makes the overall incidence of the condition difficult definition, the condition has emerged as one of the to track. Complicating matters, the recognized most controversial topics in musculoskeletal medicine prevalence of the diagnosis varies between disciplines. and rehabilitation.5 This controversy extends to For example, Campbell and Landau8 estimated that almost every aspect of the pathology including the surgeons diagnose TOS 100 times more frequently definition, the incidence, the pathoanatomical con- than neurologists. Cherington and Cherington5 go tributions, diagnosis and treatment.6,7 further to imply that the diagnosis is made by The controversy surrounding the definition exists surgeons according to potential reimbursement avail- because the term TOS only outlines the location of able for particular surgical procedures. Regardless of the problem without actually defining what comprises the overall incidence of TOS, it is estimated that over the problem. In response, investigators have categor- 90% of all TOS cases are of neurogenic origin, ized TOS as vascular versus neurogenic, where whereas less than 1% are arterial and approximately 7 vascular TOS can be subcategorized as either arterial 3–5% are venous. Neurogenic TOS has been further subcategorized as either true neurogenic or disputed neurogenic, with the former being defined as a Correspondence to: P S Sizer Jr, Department of Rehabilitation Sciences, condition with objective diagnostic findings and the School of Allied Health Sciences, Texas Tech University Health Sciences Center, 3601 4th St., Lubbock, TX, USA. Email: [email protected] latter being a condition without the same objective

ß W. S. Maney & Son Ltd 2010 74 DOI 10.1179/106698110X12640740712734 Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 Hooper et al. Thoracic outlet syndrome: Part 1

findings.9 As a result, disparities in the definition have produced different opinions regarding diagnostic standards for TOS.6,7,9,10 Furthermore, given the controversy surrounding the definition and diagnosis of TOS, conflict exists regarding the optimal treat- ment approach for this condition.10–12 The purpose of this paper is to provide the reader with clarity through: (1) a review of the relevant pathoanatomy; (2) a discussion regarding pathology and differential diagnosis; and (3) a presentation of the examination and special test measures, along with suggested diagnostic paradigms. A second manuscript (part 2 of this series) will examine both non-surgical and surgical management strategies appropriate for the treatment of TOS.

Review of pathoanatomy The neural container described as the ‘thoracic outlet’ Figure 1 Diagram showing the thoracic outlet. (A) Clavicle; is comprised of several components. Proximally, the (B) first rib; (C) coracoid process; (D) middle scalene; (E) cervicoaxillary canal is divided by the first rib into posterior scalene; (F) brachial plexus; (G) subclavian artery; (H) pectoralis minor; (I) sternocleidomastoid. two sections. The proximal portion of this canal is comprised of the interscalene triangle and the or manubrium of sternum; (2) type II: incomplete costoclavicular space, whereas the axilla comprises cervical ribs with a free end expanded to form a the distal aspect of the canal. The proximal portion is bulbous tip; (3) type III: an incomplete rib that is more clinically relevant, due to its role in neurovas- continued by a fibrous band; and (4) type IV: a rib cular compression.12 More specifically, the thoracic that appears as a short bar of bone with a length of a outlet includes three confined spaces extending from few millimeters beyond the C7 transverse process. the cervical spine and mediastinum to the lower Additionally, an elongated C7 transverse process can border of the pectoralis minor muscle (Fig. 1). The produce neurovascular compression. Conversely, an three compartments include the interscalene triangle, the costoclavicular space and the thoraco-coraco- abnormal first rib or clavicle can create compression 4,13 through exostosis, tumor, callus or fracture of the pectoral space or retropectoralis minor space. The 13 interscalene triangle is bordered by the anterior first rib, subsequently irritating the brachial plexus. 17 scalene muscle anteriorly, the middle scalene muscle When a clavicular fracture demonstrates malunion, 18 19 posteriorly, and the medial surface of the first rib fragmentation, or retrosternal dislocation, the inferiorly. risk for TOS is enhanced. The trunks of the brachial plexus and subclavian Soft tissue abnormalities may create compression artery are located in the interscalene triangle.12 The or tension loading of the neurovascular structures subclavian vein does not cross the interscalene found within the thoracic outlet container. For triangle but runs beneath the anterior scalene before example, congenital abnormalities have been joining the internal jugular vein to form the reported and include several anatomic variations of 13 brachiocephalic vein. The costoclavicular space is the scalene muscles. Demondion et al. reported bordered anteriorly by the middle third of the that scalene muscle variations include hypertrophy clavicle, posteromedially by the first rib, and poster- of the anterior scalene muscle, passage of the olaterally by the upper border of the scapula.4 The brachial plexus through the substance of the anterior borders of the thoraco-coraco-pectoral space include scalene muscle, and a broad, excessively anterior the coracoid process superiorly, the pectoralis minor middle scalene muscle insertion on the first rib. anteriorly and the ribs 2 through 4 posteriorly Further complicating the soft tissue compromised (Fig. 1).14,15 within the thoracic outlet, anomalous fibrous bands Several types of bony abnormalities exist that have been found within the thoracic outlet container, produce the compromising events related to TOS. increasing the stiffness and decreased compliance of Cervical ribs are supranumerary ribs originating from the container, resulting in an increased potential for the seventh cervical vertebra and occur in less than neurovascular load.20 These congenital abnormal- 1.0% of the general population, with only 10% of ities can be visualized by magnetic resonance those patients with the rib experiencing symptoms imaging. In addition, an indirect sign of the presence affiliated with its presence.16 Samarasam et al.3 found of a tight fibrous band is elevation of the subclavian four main varieties of cervical ribs including: (1) type artery demonstrated on sagittal magnetic resonance 13 I: a complete cervical rib articulates with the first rib imaging. Roos classified 10 different types of

Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 75 Hooper et al. Thoracic outlet syndrome: Part 1

fibrous bands that tend to stiffen the already History and clinical examination unforgiving boundaries of the thoracic outlet con- Diagnosing TOS can be challenging because the tainer. These anomalous structures traverse through symptoms vary greatly amongst patients with the the thoracic outlet and tend to reduce thoracic outlet disorder, thus lending to other conditions including a 33,34 container compliance, potentially elevating, kinking double crush syndrome. Diagnoses of the two and compressing the neurovascular bundle against vascular forms of TOS are generally accepted in all the surrounding anatomic borders of the thoracic healthcare circles. On the other hand, neurogenic outlet.20,21 TOS, especially ‘disputed’ neurogenic TOS, is more Because the thoracic outlet is bordered by the difficult to diagnose because there is no standard 35 clavicle, clavicular movement is essential for normal objective test to confirm clinical impressions. thoracic outlet container compliance. The normal Acarefulhistoryandthoroughclinicalexamina- clavicle is expected to elevate, retract and spin tion are the most important components in estab- 36 backwards during upper extremity elevation.22 lishing the diagnosis of TOS, which remains a However, if this behavior is compromised, then the diagnosis of exclusion. As such, other conditions thoracic outlet container could be reduced and the that present with overlapping or similar clinical brachial plexus placed at risk for increased load. This pictures must be considered during the examination 21 increased load could lead to direct neural compres- process. Further challenges are found in the fact sion, angulation, or tension loading.23 that the diagnosis of entrapment neuropathies of the Clavicular movement is influenced by the struc- upper limb does not exclude TOS, constituting a tural and functional integrity of both the acromio- double crush that is observed in approximately 33,37,38 clavicular joint (ACJ) and sternoclavicular joint 50% of cases. (SCJ). The ACJ allows movement of the scapula on the clavicle in three planes about the coronal, sagittal, Patient history and vertical axes.24,25 Ligamentous support for the Vascular TOS can develop secondary to repetitive ACJ (ACJ capsular ligaments) serves as a primary upper limb activities that lead to claudication, restraint for posterior axial rotation and posterior especially in young adults with arterial TOS. displacement of the clavicle on the acromion.24,26 The However, the same condition can develop sponta- integrity of the ACJ is indirectly controlled by the neously, unrelated to trauma. Conversely, neurogenic coracoclavicular ligament complex (trapezoid and TOS more commonly develops following a macro- conoid ligaments), which provides 75% of the trauma to the neck or shoulder girdle area, such as a constraint against axial compression of the clavicle motor vehicle accident or work-related repetitive toward the acromion.24–26 Moreover, this complex stressful activities.7 Table 1 summarizes the clinical tension loads during arm elevation, producing dorsal profile associated with vascular and neurogenic axial rotation of the clavicle about its longitudinal TOS.7,31 axis. Any compromise to this movement could Signs and symptoms of TOS vary with every contribute to TOS by compromising the container patient according to the location of the neurovascular and loading the nerve tissue. tension and/or compression injury within the thoracic The SCJ is a diarthrodial, synovial, sellar joint. The outlet. Symptoms of TOS can range from mild pain various ligament systems (costoclavicular and sterno- and sensory changes to limb- and/or life-threatening clavicular) reinforce the capsule and limit anterior- complications.29,39 Patients can present with multiple posterior movement of the medial end of the clavicle. unilateral or bilateral signs and symptoms associated The SCJ can be susceptible to anterior and posterior with involvement of both neurogenic and vascular subluxations via direct and indirect trauma.24,27 Any components.40 dysfunction of the clavicle associated with either a The quality, location and timing of symptoms all limit or subluxation of the SCJ can contribute to present valuable information to the clinician. Arterial thoracic outlet compromise and subsequent symptom TOS, while infrequent, can produce a series of development. profound symptoms. Patients suffering from this condition can present with pain, numbness in a non- Epidemiology radicular distribution, coolness to touch and pale While the majority of TOS cases are diagnosed discoloration, all of which worsen with cold ambient between the ages of 20 and 50 years,4 TOS can occur temperatures.41 Conversely, venous TOS results in in teenagers28 or more rarely in pediatric patients.29 excruciating deep pain the chest, shoulder and entire Women are three to four times more likely to develop upper extremity, accompanied by a feeling of heavi- neurogenic TOS,30 while the incidence of vascular ness that occurs especially after activity. The patient TOS is more equal between non-athletic men and will present with cyanotic discoloration and dis- women,31 but found to be even greater in competitive tended collateral veins, potentially accompanied by athletic men versus women.32 edematous increases in the volume of the extremity.42

76 Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 Table 1 Clinical profile and diagnosis of TOS

ArterialTOS VenousTOS TrueneurogenicTOS DisputedneurogenicTOS

Often in young adults with a Pain, often in younger men and often Common history of neck trauma preceding Common history of neck trauma preceding the symptoms, history of vigorous arm preceded by the symptoms, most commonly from car accidents and activity or spontaneous excessive activity most commonly from car accidents and repetitive repetitive stress at work. in the arms or spontaneous stress at work. Pain in the hand but seldom Edema of the arm Pain, paresthesia, numbness and/or weakness Pain, paresthesia, and feeling of in the shoulder or neck in the hand, arm (C8, T1 distribution) weakness in the hand, arm (C8, T1 distribution) and shoulder, plus neck pain and shoulder, plus neck pain Pallor Cyanosis Occipital headaches Occipital headaches Claudication Feeling of heaviness Paresthesias, numbness during the day Paresthesias, often nocturnal, and also nocturnal, awakening the patient awakening the patient with pain or paresthesia with pain or numbness ora fMna n aiuaieTherapy Manipulative and Manual of Journal Coldness and cold intolerance Paresthesias in the fingers and hand Loss of dexterity Loss of dexterity (secondary to edema) Paresthesias Cold intolerance Cold intolerance Symptoms usually stem Raynaud phenomenon, hand coldness, Raynaud phenomenon, hand coldness, spontaneously and color changes due to sympathetic and color changes due to sympathetic from arterial emboli. overactivity as opposed to ischemia. overactivity as opposed to ischemia. ‘Compressors’: symptoms day.night ‘Releasers’: symptoms night.day Objectified weakness and/or sensory Subjective weakness and/or deficit5‘true’ neurogenic numbness5‘disputed’ neurogenic Diagnosis based on information Diagnosis based on information above Diagnosis based on information Diagnosis based on information above abovezcluster of at least abovezcluster of at least two provocation two provocation tests positive and tests positive and often presence of almost always elevated arm cyriax release test (z) stress test (z) al. et Hooper Confirmed through doppler Confirmed through venous ultrasound studies, Confirmed through (z) No confirmation through objective ultrasound and angiography in venous scintillation scans, venography neurophysiological testing testing neurophysiological testing are normal the seated position and plethysmography 2010 hrccote ydoe at1 Part syndrome: outlet Thoracic VOL .18 NO .2 77 Hooper et al. Thoracic outlet syndrome: Part 1

Symptoms associated with neurogenic TOS brachial plexus. These patients can be referred to as include pain, paresthesia,numbness,and/orweak- ‘compressors’. ness. Here, the examiner should investigate if the symptoms are radicular or non-radicular in nature. Clinical examination Thoracic outlet symptoms will normally not produce The examiner should record the position of the symptoms that follow dermatomal and myotomal patient’s head, shoulders, scapulae and arms in the patterns, unless the thoracic outlet is accompanied seated and standing positions. The examiner should by cervical or upper thoracic nerve root compres- pay attention to the presence of rounded shoulders, sion. Reports of paresthesia in the upper limb forward head, increased thoracic kyphosis, as well as indicate mild perineural dysfunction,43 while objec- posterior tilt, downward rotation and/or depression tified numbness and/or weakness suggest true axonal of the scapulae. These postures tend to increase the 50 compression, which is indicative of a more serious tension loading of the brachial plexus. Moreover, insult and a less favorable prognosis.44 Symptoms’ the patient may present with supraclavicular fullness, which could represent a first rib prominence versus location most frequently reported in patients with 51 TOS include paresthesia in the upper limb (98%), soft tissue swelling. neck pain (88%), trapezius pain (92%), shoulder and/ Visual inspection of the upper limbs includes observing for cyanosis and edema in case of venous or arm pain (88%), supraclavicular pain (76%), chest compromise or paleness in case of vascular compro- pain (72%), occipital headache (76%), and parasthe- mise (as previously described). Atrophy in the hand sias in all five fingers (58%), the fourth and fifth region should additionally be noted. If the patient has fingers only (26%) or the first–third fingers (14%).7 a cervical rib or an elevated first rib, the supraclavi- Compression and irritation of the upper plexus (C5, cular fossa may appear to be full.51 C6, C7) can cause pain in the anterior aspect of the The supraclavicular fossa, including the brachial neck from the clavicle to the mandible, ear and plexus found in the space, should be palpated for mastoid area, occasionally radiating into the side of pain.52 The brachial plexus is best palpated directly the face. These symptoms can spread into the upper posterior to the pulsation of the subclavian artery chest anteriorly, the periscapular region posteriorly, with the head sidebent toward the contralateral side. and across the trapezius ridge down the outer arm The patient’s hands are palpated for temperature and through the radial nerve distribution toward the changes and moistness for the sake of detecting dorsum of the thumb and index finger.20 Patients sympathetically mediated symptoms. with this distinct pattern of symptoms may have The clinical examination begins by questioning the pathoanatomical anomalies that are typically multi- patient about the location and amplitude of present ple, most often located in the posterior scalenic 45,46 symptoms, such as pain. The patient is asked to triangle between the anterior and middle scalene report changes in the symptoms’ amplitude asso- muscles20 and occasionally compressed by a scalenus 47 ciated with movements of the neck, shoulder girdle minimus muscle. Patients with lower plexus (C8, and upper limb. T1) irritation will mainlycomplainofsymptomson In suspecting thoracic outlet problem, the cervical the ulnar side of the arm and hand, potentially spine and shoulders should be examined. A descrip- accompanied by symptoms found in the anterior tion of cervical and shoulder clinical examination are shoulder and axillary regions. beyond the scope of this discussion and are described Historical questioning should include the timing of elsewhere.25,53 The decision to perform specific symptoms, which may occur throughout the day clinical testing for TOS is based on the examiner’s 48 during activity versus only present at night. Many clinical reasoning and is carried out mainly in the patients report awaking at night with paresthesia in presence of neck–shoulder–arm symptoms that are the upper limb, a phenomenon coined in the non-radicular in nature and influenced by the 49 literature as the ‘release phenomenon’. This phe- position of the upper limb and/or neck. If the testing nomenon suggests release of tension and/or compres- of the cervical spine, shoulder and TOS are negative, sion of the perineural blood supply to the brachial a peripheral compression neuropathy is suspected54 plexus and signals a return of normal sensation that is and further testing should be performed in order to a prognostic indicator of favorable outcome. The focus on those possibilities. clinician can refer to these patients as ‘releasers’. On The diagnosis of arterial, venous and true neuro- the other hand, other patients may experience their genic TOS has the advantage of implementing symptoms primarily throughout the day time while standard diagnostic tests. The validity of vascular using prolonged postures (such as shoulder girdles diagnostic tests is improved when performed dyna- protracted and depressed and the head forward) or mically in the positions that produce the patient’s activities (such as working over head with elevated symptoms.55 The following diagnostic tests have been arms) that would result in an increase in tension or recommended: (1) venous ultrasound studies, venous compression of the neurovascular bundle of the scintillation scans, venography and plethysmography

78 Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 Hooper et al. Thoracic outlet syndrome: Part 1 for venous TOS;31 (2) Doppler ultrasound and and upper limb but is not specific for one area. The angiography in the seated position for arterial test is recommended as part of the examination and TOS;55 and (3) nerve conduction velocities and for its usefulness in treatment that includes neural electromyography of the medial antebrachial cuta- mobilization.66,67 neous nerve for the true neurogenic TOS.30,56 Each of the previously discussed tests should be Conversely, no valid standard diagnostic test is considered when establishing a diagnosis of TOS. available for disputed neurogenic TOS, resulting in From Table 2, one can see that the validity of any controversies in the frequency of TOS diagnosis.57,58 single test is troubled. In view of the lack of quality Commonly, nerve conduction velocities and electro- research reporting both sensitivity and specificity of myography are negative for disputed neurogenic TOS provocation testing, Gilliard et al.61 showed that TOS. Thus, the examiner must rely on a thorough a cluster of two provocative tests displayed the history and a cluster of clinical TOS provocation test highest sensitivity (90%), while a cluster of five findings to solve the disputed neurogenic TOS positive provocative tests increased the specificity diagnostic puzzle. for TOS to 84%. Provocative clinical testing for TOS has been A comprehensive diagnosis of disputed neurogenic reported to display high rates of false positive TOS is supported based on several levels of assess- findings.59 The reliability and validity of provocative ment. First, the diagnosis is supported based on a clinical tests for TOS and one motion test for history that includes the presence of non-radicular assessment of the presence of an elevated first rib symptoms in the neck–shoulder–arm worsened by are summarized in Table 2. The supraclavicular movements and/or position of the neck, arms, and pressure test and the Adson’s test more specifically shoulder girdle, accompanied by the presence of a address compromise to the plexus through the scalene cluster of TOS provocation tests. Next, the diagnostic triangles.54 The costoclavicular maneuver evaluates picture is completed with an assessment of postural provocation produced by costoclavicular space nar- dysfunctions and container mobility (thoracic outlet rowing, while the Wright’s test examines neural tissue container testing). As stated earlier, the examiner compromise through the thoraco-coraco-pectoral should record the presence of rounded shoulders, gate.54 The elevated arm stress test examines the forward head, and increased thoracic kyphosis, as result of loading the plexus throughout the TOS well as posterior tilt, downward rotation and/or container, while the Cyriax release test examines the depression of the scapulae.50 The mobility of the first result of unloading the plexus in the same space. rib can be assessed using the cervical rotation lateral Finally, the upper limb neural tension test examines flexion test (Table 2),9 as an elevated first rib can provocation to the neural tissue passing through the potentially increase the tension on the neurovascular thoracic outlet container under a tension load. bundle of the brachial plexus. The mobility of the The Adson’s test and costoclavicular maneuver thoracic spine should be carefully assessed for lack of display a fairly large percentage of false positives motion, especially in the direction of extension.68 when a change in the radial pulse is considered as a This assessment should be accompanied by an positive test.60,61 Therefore, the clinician is encour- appraisal of the muscle length of the scalene muscles, aged to use the test position of those tests for especially in weight lifters, patients with severe symptom provocation and not as a test for radial chronic obstructive pulmonary disease and after pulse change. This is sensible, considering the low whiplash. Shortening of these muscles can lead to incidence of vascular involvement in TOS. non-compliance of the thoracic outlet container Conversely, one can note from examining tabulated through its gates.7,69 data that the Wright’s test and the elevated arm stress To continue the assessment of the thoracic outlet test appear to display the greatest sensitivity for container, the motion of the clavicle should be neurogenic and vascular TOS. The positive Cyriax assessed during arm elevation, looking for decreased release test62 represents a ‘release phenomenon’, mobility. When hypomobile, the clavicle moves too which is most relevant when correspondent to a quickly in a dorsal direction and produces a history of nocturnal symptoms. These findings can be narrowing of the costoclavicular space.54 In such a used as a treatment guide. case the joint play tests of the ACJ and SCJ should be Upper limb tension testing is sensitive for irritation carried out. Hypomobility of these joints could lead of the neural tissue including cervical roots,63 to dysfunction in the movement of the clavicle and brachial plexus and peripheral nerves64 as well as shoulder girdle, thus crowding the thoracic outlet for patients with arm pain syndrome.65 It has been container through which the brachial plexus advocated for the diagnosis of neurogenic TOS with courses.54 Finally, glenohumeral end-range mobility reported high sensitivity.7 The test appears to be testing is merited, where limits could force the clavicle excellent for screening for sensitization of the to compromise the brachial plexus during end-range neural tissue in the cervical spine, brachial plexus arm elevation.

Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 79 opre al. et Hooper 80 ora fMna n aiuaieTherapy Manipulative and Manual of Journal Table 2 Description, reliability, sensitivity, specificity, and likelihood ratios of clinical tests for TOS hrccote ydoe at1 Part syndrome: outlet Thoracic Test Description Reliability Sensitivity Specificity LRz LR2 References

Elevated arm stress Patient seated with arms above 90 degrees of abduction 1.0 52–84 30–100 1.2–5.2 0.4–0.53 33, 60, 61, 70–72 and full external rotation with head in neutral position. Patient opens and closes hands into fists while holding the elevated position for 3 minutes. Positive test: pain and/or paresthesia and discontinuation with dropping of the arms for relief of pain. Supraclavicular pressure Patient seated with arms at the side. Examiner places NT NT 85–98 NA NA 60, 72 fingers on the upper trapezius and the thumbs contacting the anterior scalene muscle near the first ribs and squeezes the fingers and thumb together for 30 seconds. Positive test: reproduction of pain or paresthesia. Costoclavicular maneuver Patient sits straight with arms at the side. Radial pulse is assessed. NT NT 53–100 NA NA 60, 70, 72 Patient retracts and depresses shoulders while protruding the chest. 2010 Position is held for up to 1 minute. Positive test: change in radial pulse and/or pain and paresthesia. Adson’s Patient seated with arms at the side. The radial pulse is palpated. NT 79 74–100 3.29 0.28 60, 61, 70, 72

VOL Patient inhales deeply and holds the breath, extends and rotates

.18 the neck toward the side being tested. Positive test: change in radial pulse and/or pain, paresthesia reproduction. Wright’s Patient seated with arms at the side. The radial pulse is palpated. NT 70–90 29–53 1.27–1.49 0.34–0.57 61

NO Examiner places the patient’s shoulder into abduction above .2 the head. The position is held for 1 to 2 minutes. Positive test: change in radial pulse and/or symptom reproduction. Cyriax release Patient seated or standing. Examiner stands behind patient 0.92 NT 77–97 NA NA 33, 62 and grasps under the forearms, holding the elbows at 80 degrees of flexion with the forearms and wrists in neutral. Examiner leans the patient’s trunk posteriorly and passively elevates the shoulder girdle. The position is held for up to 3 minutes. Positive test: Paresthesia and/or numbness (release phenomenon) or symptom reproduction. Upper limb tension Patient supine. Examiner standing on the side to be tested. 0.03 90 38 1.5 0.3 65, 73, 74 Examiner depresses the shoulder girdle and abducts the shoulder to 110 degrees with slight extension and elbow flexion to 90 degrees. The forearm is then maximally supinated and the wrist and fingers extended. Finally, elbow extension is applied. The neck is sidebent to the contralateral side. Testing is stopped after any symptom reproduction. Positive test: reproduction of symptoms with the distal movement or neck movement and/or restricted elbow extension range of motion. Cervical rotation lateral flexion Patient seated. Examiner passively rotates the head away from 0.42–1.0 100 NT NA NA 9, 75 the affected side and gently flexes the neck forward to end range moving the ear toward the ventral chest. Positive test: forward flexion part of the movement is notably decreased with a hard end feel.

Note: LRz: positive likelihood ratio; LR2: negative likelihood ratio. Hooper et al. Thoracic outlet syndrome: Part 1

The clinician must consider the presence of elsewhere59 and is beyond the scope of this discus- associated neural tissue irritations/entrapments along sion. However, due to the potential for a double the entire course of the peripheral nerves associated crush event, nerve irritation/compression/tension at with the brachial plexus. Rather than trying to the brachial plexus (TOS) can lend selected peripheral differentiate TOS from a peripheral nerve entrapment nerves to greater vulnerability and subsequent as the sole cause of the patient’s symptoms, the symptoms in the sites distal to the thoracic outlet. clinician is encouraged to consider the possibility of As a consequence, the patient suffering from entrap- both conditions that result from a double crush event ment in the thoracic outlet is at risk for developing a of the neural tissues along their course. In response, a symptom profile that reflects both the TOS condition clinician’s suspicion for the relative contribution of and the other irritation/entrapment(s). Thus, the TOS versus a peripheral nerve entrapment is influ- clinician is encouraged to perform testing that is enced through the analysis of outcomes from the relevant both to TOS and the peripheral nerve clinical testing ensemble. irritation/entrapment. A description of relevant testing for peripheral The potential for double crush complicates the nerve structures and their resultant irritations/entrap- clinical presentation and makes a differential diag- ments (including ulnar nerve at the cubital tunnel and nostic process challenging for the clinician. Once the tunnel of Guyon, dorsal interosseus nerve in the previously described testing (TOS provocation test- tunnels of the dorsal forearm, median nerve at both ing, Thoracic outlet container testing, and peripheral the pronator teres and carpal tunnel) is offered nerve irritation/entrapment testing) is completed,

Table 3 Double crush considerations for disputed neurogenic TOS

Peripheral TOS Thoracic outlet nerve provocation container provocation tests* testing{ tests{ Interpretation Management decisions

(2)(2)(2) Low suspicion for TOS and or Further testing merited peripheral nerve irritation/ before management is initiated entrapment condition. Symptoms are likely due to other condition, such as cervical spine or central nervous system. (z)(2)(2) High suspicion for TOS without Treat TOS for associated thoracic outlet symptom management container dysfunction; low suspicion for peripheral nerve irritation/entrapment (z)(z)(2) High suspicion for TOS with Treat TOS for symptom associated thoracic outlet management and container dysfunction; improvement of thoracic low suspicion for peripheral outlet container mobility nerve irritation/entrapment (z)(2)(z) High suspicion for TOS without Treat TOS for symptom associated thoracic management; treat peripheral outlet container dysfunction; nerve irritation/entrapment high suspicion for peripheral nerve irritation/entrapment; high suspicion for double crush (z)(z)(z) High suspicion for TOS with Treat TOS for symptom associated thoracic outlet management and improvement container dysfunction; of thoracic outlet container high suspicion for peripheral mobility; treat peripheral nerve irritation/entrapment; nerve irritation/entrapment high suspicion for double crush (2)(z)(z) Low suspicion for TOS; high Treat for improvement of thoracic suspicion for thoracic outlet outlet container mobility; container dysfunction; high Treat peripheral suspicion for peripheral nerve nerve irritation/entrapment irritation/entrapment; high suspicion for double crush. (2)(2)(z) Low suspicion for TOS; low Treat peripheral nerve suspicion for thoracic outlet irritation/entrapment container dysfunction; high suspicion for isolated peripheral nerve irritation/entrapment; low suspicion of double crush.

*For any UE symptoms; A (z) cluster of tests increases the suspicion. {For mobility loss/dysfunction in any joint system in the container, such as first rib, ACJ, or SCJ. {For specific peripheral nerve symptoms provoked through peripheral nerve clinical provocation testing.

Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 81 Hooper et al. Thoracic outlet syndrome: Part 1

then the clinician is left to interpret the clinical testing 5 Cherington M, Cherington C. Thoracic outlet syndrome: Reimbursement patterns and patient profiles. Neurology. results. Table 3 presents a suggested approach to 1992;42:943–5. interpreting test results and clinical decision making 6 Cuetter AC, Bartoszek DM. The thoracic outlet syndrome: controversies, overdiagnosis, overtreatment, and recommenda- for patients with potential complex presentations. tions for management. Muscle Nerve. 1989;12:410–9. The interpretation of said tests raises or lowers the 7 Sanders RJ, Hammond SL, Rao NM. Diagnosis of thoracic outlet syndrome. J Vasc Surg. 2007;46:601–4. clinician’s suspicion for any combination of the 8 Campbell WW, Landau ME. Controversial entrapment neuro- following: TOS, thoracic outlet container dysfunc- pathies. Neurosurg Clin N Am. 2008;19:597–608, vi–vii. tion, peripheral nerve irritation/entrapment, and 9 Lindgren KA, Leino E, Manninen H. Cervical rotation lateral flexion test in brachialgia. Arch Phys Med Rehabil. underlying double crush. Without consideration for 1992;73:735–7. related peripheral nerve irritations/entrapments and 10 Lindgren KA, Oksala I. Long-term outcome of surgery for thoracic outlet syndrome. Am J Surg. 1995;169:358–60. potential double crush, the management of complex 11 Cherington M. Thoracic outlet syndrome: rise of the con- patients may be incomplete. servative viewpoint. Am Fam Physician. 1991;43:1998. 12 Urschel HC, Kourlis H. Thoracic outlet syndrome: a 50-year experience at baylor university medical center. Proc (Bayl Univ Summary Med Cent). 2007;20:125–35. The diagnosis and management of TOS has remained 13 Demondion X, Herbinet P, van Sint Jan S, Boutry N, Chantelot C, Cotten A. Imaging assessment of thoracic outlet syndrome. controversial, based on a potential lack of corre- Radiographics. 2006;26:1735–50. spondence between neurophysiological testing and 14 Richardson AB. Thoracic outlet syndrome in aquatic athletes. Clin Sports Med. 1999;18:361–78. clinical examination outcomes. An appreciation for 15 Remy-Jardin M, Doyen J, Remy J, Artaud D, Fribourg M, the complexity of the anatomical and mechanical Duhamel A. Functional anatomy of the thoracic outlet: evaluation with spiral CT. Radiology. 1997;205:843–51. features associated with the thoracic outlet container 16 Wood VE, Twito R, Verska JM. Thoracic outlet syndrome. The can serve as a foundation for understanding a results of first rib resection in 100 patients. Orthop Clin North patient’s clinical presentation. A thorough historical Am. 1988;19:131–46. 17 Fujita K, Matsuda K, Sakai Y, Sakai H, Mizuno K. Late account and clinical examination can guide the thoracic outlet syndrome secondary to malunion of the clinician towards a selection of specific tests that will fractured clavicle: case report and review of the literature. J Trauma. 2001;50:332–5. support the diagnostic process. The accuracy of 18 Chen DJ, Chuang DC, Wei FC. Unusual thoracic outlet numerous tests has been established, and a clinician syndrome secondary to fractured clavicle. J Trauma. 2002;52:393–8; discussion 398–9. can implement these tests to strengthen a diagnostic 19 Jain S, Monbaliu D, Thompson JF. Thoracic outlet syndrome suspicion. This is especially important when neuro- caused by chronic retrosternal dislocation of the clavicle. Successful treatment by transaxillary resection of the first rib. physiological testing contradicts the clinical presenta- J Bone Joint Surg Br. 2002;84:116–8. tion. Rather than trying to differentiate TOS from a 20 Roos DB. Historical perspectives and anatomic considerations. peripheral nerve entrapment as the cause of the thoracic outlet syndrome. Semin Thorac Cardiovasc Surg. 1996;8:183–9. patient’s symptoms, the clinician is encouraged to 21 Sheth RN, Belzberg AJ. Diagnosis and treatment of thoracic consider the possibility of both conditions that result outlet syndrome. Neurosurg Clin N Am. 2001;12:295–309. 22 Fung M, Kato S, Barrance PJ, Elias JJ, McFarland EG, from a double crush irritation of the neural tissues Nobuhara K, et al. Scapular and clavicular kinematics during along their course. In response, a clinician’s suspicion humeral elevation: a study with cadavers. J Shoulder Elbow Surg. 2001;10:278–85. for the relative contribution of TOS versus a 23 Fisher MA, Gorelick PB. Entrapment neuropathies. peripheral nerve entrapment is influenced through Differential diagnosis and management. Postgrad Med. the analysis of outcomes from the clinical testing 1985;77:160–74. 24 Culham E, Peat M. Functional anatomy of the shoulder ensemble. complex. J Orthop Sports Phys Ther. 1993;18:342–50. Once a thorough history and clinical examination 25 Sizer PS, Phelps V, Gilbert K. Diagnosis and management of the painful shoulder. Part 1: clinical anatomy and pathome- is completed, the clinician can decide upon a chanics. Pain Practice. 2003;3:39–57. management strategy appropriate for the individual 26 Renfree KJ, Wright TW. Anatomy and biomechanics of the acromioclavicular and sternoclavicular joints. Clin Sports Med. patient. Part 2 will discuss non-surgical, as well as 2003;22:219–37. surgical, treatment options. Non-surgical treatment 27 Wirth MA, Rockwood CA Jr. Acute and chronic traumatic injuries of the sternoclavicular joint. J Am Acad Orthop Surg. focuses on symptom reduction and addressing the 1996;4:268–78. specific dysfunctions responsible for the patient’s 28 Rigberg DA, Gelabert H. The management of thoracic outlet symptoms. Surgery is generally reserved for cases of syndrome in teenaged patients. Ann Vasc Surg. 2009;23:335– 340. vascular TOS or neurogenic TOS that does not 29 Arthur LG, Teich S, Hogan M, Caniano DA, Smead W. respond to conservative measures. Pediatric thoracic outlet syndrome: a disorder with serious vascular complications. J Pediatr Surg. 2008;43:1089–94. 30 Machanic BI, Sanders RJ. Medial antebrachial cutaneous nerve References measurements to diagnose neurogenic thoracic outlet syn- 1 Atasoy E. Thoracic outlet compression syndrome. Orthop Clin drome. Ann Vasc Surg. 2008;22:248–54. North Am. 1996;27:265–303. 31 Urschel HC,Jr, Patel AN. Surgery remains the most effective 2 Peet RM, Hendricksen JD, Anderson TP, Martin GM. treatment for paget-schroetter syndrome: 50 years’ experience. Thoracic outlet syndrome: evaluation of a therapeutic exercise Ann Thorac Surg. 2008;86:254–60; discussion 260. program. Prc Mayo Clin. 1956;31:281–7. 32 Melby SJ, Vedantham S, Narra VR, Paletta GA Jr, Khoo- 3 Samarasam I, Sadhu D, Agarwal S, Nayak S. Surgical Summers L, Driskill M, et al. Comprehensive surgical manage- management of thoracic outlet syndrome: a 10-year experience. ment of the competitive athlete with effort thrombosis of the ANZ J Surg. 2004;74:450–4. subclavian vein (Paget-Schroetter syndrome). J Vasc Surg. 4 Koknel Talu G. Thoracic outlet syndrome. Agri. 2005;17:5–9. 2008;47:809–20; discussion 821.

82 Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 Hooper et al. Thoracic outlet syndrome: Part 1

33 Smith TM, Sawyer SF, Sizer PS, Brismee JM. The double crush lesions. A report of 16 cases. Clin Neurophysiol. syndrome: a common occurrence in cyclists with ulnar nerve 2004;115:2316–22. neuropathy – a case-control study. Clin J Sport Med. 57 Roos DB. Thoracic outlet syndrome is underdiagnosed. Muscle 2008;18:55–61. Nerve. 1999;22:126–9; discussion 137–8. 34 Abe M, Ichinohe K, Nishida J. Diagnosis, treatment, and 58 Wilbourn AJ. Thoracic outlet syndrome is overdiagnosed. complications of thoracic outlet syndrome. J Orthop Sci. Muscle Nerve. 1999;22:130–6; discussion 136–7. 1999;4:66–9. 59 Cook C, Hegedus EJ. Orthopedic physical examination tests: 35 Sanders RJ, Hammond SL, Rao NM. Thoracic outlet an evidence-based approach. Upper Saddle River (NJ): syndrome: a review. Neurologist. 2008;14:365–73. PearsonPrentice Hall; 2008. 36 Rayan GM. Thoracic outlet syndrome. J Shoulder Elbow Surg. 60 Plewa MC, Delinger M. The false-positive rate of thoracic 1998;7:440–51. outlet syndrome shoulder maneuvers in healthy subjects. Acad 37 Seror P. Symptoms of thoracic outlet syndrome in women with Emerg Med. 1998;5:337–42. carpal tunnel syndrome. Clin Neurophysiol. 2005;116:2324–9. 61 Gillard J, Perez-Cousin M, Hachulla E, Remy J, Hurtevent JF, 38 Wood VE, Biondi J. Double-crush nerve compression in Vinckier L, et al. Diagnosing thoracic outlet syndrome: thoracic-outlet syndrome. J Bone Joint Surg Am. 1990;72:85–7. contribution of provocative tests, ultrasonography, electrophy- 39 Elman EE, Kahn SR. The post-thrombotic syndrome after siology, and helical computed tomography in 48 patients. Joint upper extremity deep venous thrombosis in adults: a systematic Bone Spine. 2001;68:416–24. review. Thromb Res. 2006;117:609–14. 62 Brisme´e JM, Gilbert K, Isom K, Hall R, Leathers B, Sheppard 40 Tilki HE, Stalberg E, Incesu L, Basoglu A. Bilateral neurogenic N et al. Rate of false positive using the cyriax release test for thoracic outlet syndrome. Muscle Nerve. 2004;29:147–50. thoracic outlet syndrome in an asymptomatic population. J 41 Pollack EW. Surgical anatomy of the thoracic outlet syndrome. Man Manip Ther. 2004;12:73–81. Surg Gynecol Obstet. 1980;150:97–103. 63 Wainner RS, Fritz JM, Irrgang JJ, Boninger ML, Delitto A, 42 Urschel HC Jr, Razzuk MA. Improved management of the Allison S. Reliability and diagnostic accuracy of the clinical Paget-Schroetter syndrome secondary to thoracic outlet com- examination and patient self-report measures for cervical pression. Ann Thorac Surg. 1991;52:1217–21. radiculopathy. Spine (Phila Pa 1976). 2003;28:52–62. 43 Rempel D, Dahlin L, Lundborg G. Pathophysiology of nerve 64 Mahmud MA, Merlo AR, Gomes I, Becker J, Nora DB. compression syndromes: response of peripheral nerves to Relationship between adverse neural tension and nerve loading. J Bone Joint Surg Am. 1999;81:1600–10. conduction studies in patients with symptoms of the carpal 44 Jordan SE, Ahn SS, Gelabert HA. Differentiation of thoracic tunnel syndrome. Arq Neuropsiquiatr. 2006;64:277–82. outlet syndrome from treatment-resistant cervical brachial pain 65 Quintner JL. A study of upper limb pain and paraesthesiae syndromes: development and utilization of a questionnaire, following neck injury in motor vehicle accidents: assessment of clinical examination and ultrasound evaluation. Pain Physician. the brachial plexus tension test of elvey. Br J Rheumatol. 2007;10:441–52. 1989;28:528–33. 45 Rusnak-Smith S, Moffat M, Rosen E. Anatomical variations of 66 Orset G. Evaluation of the cervicothoracobrachial outlet and the scalene triangle: dissection of 10 cadavers. J Orthop Sports results of conservative treatment. Chir Main. 2000;19:212–7. Phys Ther. 2001;31:70–80. 46 Natsis K, Totlis T, Tsikaras P, Anastasopoulos N, Skandalakis 67 Berthe A. Considerations on rehabilitation of cervicothoraco- P, Koebke J. Variations of the course of the upper trunk of the brachial outlet syndrome. Chir Main. 2000;19:218–2. brachial plexus and their clinical significance for the thoracic 68 Sobel JS, Kremer I, Winters JC, Arendzen JH, de Jong BM. outlet syndrome: a study on 93 cadavers. Am Surg. The influence of the mobility in the cervicothoracic spine and 2006;72:188–92. the upper ribs (shoulder girdle) on the mobility of the 47 Harry WG, Bennett JD, Guha SC. Scalene muscles and the scapulohumeral joint. J Manipulative Physiol Ther. brachial plexus: anatomical variations and their clinical 1996;19:469–74. significance. Clin Anat. 1997;10:250–2. 69 Kai Y, Oyama M, Kurose S, Inadome T, Oketani Y, Masuda 48 Murtagh J. The painful arm. Aust Fam Physician. Y. Neurogenic thoracic outlet syndrome in whiplash injury. J 1990;19:1423–6. Spinal Disord. 2001;14:487–93. 49 Cyriax J. Textbook of orthopedic medicine: diagnosis of soft 70 Rayan GM, Jensen C. Thoracic outlet syndrome: provocative tissue lesions. 7th ed. Vol 1. London: Baliere Tindally; 1978. examination maneuvers in a typical population. J Shoulder 50 Swift TR, Nichols FT. The droopy shoulder syndrome. Elbow Surg. 1995;4:113–7. Neurology. 1984;34:212–5. 71 Howard M, Lee C, Dellon AL. Documentation of brachial 51 Okereke CD, Mavor A, Naim M. Arterial thoracic outlet plexus compression (in the thoracic inlet) utilizing provocative compression syndrome: a differential diagnosis of painful right neurosensory and muscular testing. J Reconstr Microsurg. supraclavicular swelling? Hosp Med. 2000;61:672–3. 2003;19:303–12. 52 Liu JE, Tahmoush AJ, Roos DB, Schwartzman RJ. Shoulder- 72 Nord KM, Kapoor P, Fisher J, Thomas G, Sundaram A, Scott arm pain from cervical bands and scalene muscle anomalies. J K, et al. False positive rate of thoracic outlet syndrome Neurol Sci. 1995;128:175–80. diagnostic maneuvers. Electromyogr Clin Neurophysiol. 53 Sizer PS, Phelps V, Brisme´e JM. Differential diagnosis of local 2008;48:67–74. cervical syndrome as compared to cervico-brachial syndrome. 73 Greening J, Dilley A, Lynn B. In vivo study of nerve movement Pain Practice. 2001;1:21–35. and mechanosensitivity of the median nerve in whiplash and 54 Winkel D, Matthijs O, Phelps V. Diagnosis and treatment of non-specific arm pain patients. Pain. 2005;115:248–53. the upper extremities: nonoperative orthopaedic medicine and 74 Bertilson BC, Grunnesjo M, Strender LE. Reliability of clinical manual therapy. Gaithersburg (MD): Aspen Publishers; 1997. tests in the assessment of patients with neck/shoulder problems- 55 Cornelis F, Zuazo I, Bonnefoy O, et al. Diagnosis of thoracic impact of history. Spine (Phila Pa 1976). 2003;28:2222–31. outlet syndrome. Value of angiography in the sitting position. J 75 Gilbert KK, Brisme´e JM, Dedrick G, Delgado B, Harle J, Radiol. 2008;89:47–52. Miller J, et al. The interrater reliability of the cervical rotation 56 Seror P. Medial antebrachial cutaneous nerve conduction lateral flexion test and correlation to first rib mobility testing. J study, a new tool to demonstrate mild lower brachial plexus Man Manip Ther. 2004;12:163–4.

Journal of Manual and Manipulative Therapy 2010 VOL.18 NO.2 83