Thoracic outlet syndrome is caused by compression of the neurovascular structures in the thoracic outlet. It has three main types - neurogenic, venous, and arterial. Neurogenic TOS is the most common, caused by scalene muscle anomalies compressing the brachial plexus. Symptoms include pain, numbness, and weakness in the arm. Conservative treatments focus on postural changes, stretching, and strengthening to relieve compression. Precise diagnosis relies on clinical examination, and surgery may be considered if conservative measures fail.

1. THORACIC OUTLET SYNDROME
 Anything that narrows Costoclavicular space

2. DEFINITION
Thoracic outlet syndrome (TOS)- a collection of
symptoms brought about by abnormal
compression of the neurovascular bundle by bony,
ligamentous or muscular structures in the narrow
space between clavicle and 1st rib – the thoracic
outlet.

3.  Thoracic outlet is bounded
Anteriorly: Manubrium Sterni
Posteriorly: Spine
Laterally: First Rib

6. ANATOMY
• The thoracic outlet is composed of five successive spaces the
vascular and nervous elements go through :
o The inter costo scalenic defile
o The prescalenic defile
o The costoclavicular space
o The sub-pectoral tunnel
o The humeral space

7. The intercosto-scalenic defile

8. Prescalenic defile

10.  Cervico axillary canal divided into
PROXIMAL COSTOCLAVICULAR SPACE
DISTAL AXILLA.

11.  Costoclavicular space is bounded by
Superiorly: Clavicle
Inferiorly: First Rib
Antero medially: Costo clavicular Ligament
Postero laterally: Scalenus medius muscle

13.  Scalenus Anticus muscle divides costoclavicular space into 2
compartments
Anteriorly: Subclavian vein
Posteriorly: Subclavian Artery and Brachial Plexus
 Posterior compartment is called Scalene triangle bounded
Anteriorly: Scalenus Anticus
Posteriorly: Scalenus Medius
Inferiorly: 1st Rib

15. Interscalene triangle

17. Subcoracoid area

18. Pectoralis minor muscle and coracoid process

19. First clinical description given by
A.Cooper 1821
W H Willshire described about
cervical rib
H Coote first resection of cervical rib.
In 1956 Peet introduced the term
thoracic outlet syndrome.

20. contents
• viscera
– thymus
– trachea
– oesophagus
– lung apices
• vessels, nerves and
lymphatics
– common carotid arteries
– confluences of internal
jugular and subclavian
veins
– phrenic nerves
– vagus nerves
– recurrent laryngeal nerves
– thoracic duct
• prevertebral fascia
• muscles
– sternocleidomastoid
muscle
– anterior and middle
scalene muscles
– sternohyoid muscle
– sternothyroid muscle

21. Principal Causes of TOS

22. • Race
No racial predilection exists.
• Sex
Thoracic outlet syndrome is traditionally more common in women
than in men, with a female-to-male ratio as high as 3:1.
• Age
Thoracic outlet syndrome is most common in people aged 10-50
years

23. Classification

24. Subgroup 1 - (neurologic)
 –95% of cases
 This type is secondary to compression of the brachial plexus
caused by various soft tissue and bony abnormalities at the
point where the nerves pass between the anterior and middle
scalene muscles

25. Subgroup 2 - (venous type)
 3-4% of cases.
 Venous thrombosis may be categorized into primary and secondary
thrombosis based on the etiology.
 Primary venous thoracic outlet syndrome, or primary venous thrombosis,
is also called Paget-Schrötter syndrome named after the 2 individuals
who first described this entity: Paget, who described it in 1875, and von
Schrötter, in 1884.

26. Subgroup 3 (arterial type):
 1-2% of cases.
 This type is associated with the most serious complications,
including limb ischemia (which may result in the loss of the
affected upper extremity).

27. Neurogenic TOS
Etiology
 Hyperextension neck injury (whiplash)
 Repetitive stress injuries

28. Predisposing Factors
 Scalene muscle anomalies
 Narrow scalene triangles
 Congenital ligaments/bands
 Cervical ribs

29. Pathophysiology
 Neck trauma stretches and tears scalene muscle fibers
 Swelling of muscle belly
 pain, parathesias, numbness, weakness
 Scarring/fibrosis of muscle belly
 occipital headaches.

30. Symptoms
 Pain, parathesias, numbness, weakness throughout affected hand/arm
 Not necessarily localized to peripheral nerve distribution
 Extension to shoulder, neck, upper back
 Upper plexus” disorders
 “Lower plexus” disorders
 Occipital headaches
 Perceived muscle weakness
 Actual weakness and atrophy are rare
 Vasomotor symptoms
 Vasospasm, edema, hypersensitivity (CRPS)

31.  Neurologic compression
 Pain and/or parasthesia of the neck, shoulder region, arm or hand,
depending on the root involved
 Often bilateral
 Difficulty with fine motor tasks of the hand
 Examination reveals :sensitive disorders
muscle weakness
muscle atrophy (long fingers flexors)
 Palpation of subclavicular area may cause pain

32. Pectoralis minor syndrome
 Compression of neurovascular bundle under the pectoralis
minor
 Pain over anterior chest and axilla
 Fewer head/neck symptoms

33. Venous TOS
Etiology
 Developmental anomalies of costoclavicular space
 Repetitive arm activities – throwing, swimming, overhead activities.

34. Predisposing Factors
 Relationship of vein to subclavius tendon and costoclavicular ligament
 Decrease in dimensions of costoclavicular space
 Repetitive trauma to vein
 causing stenosis, thrombosis

35. 1. Acute occlusion
 Pain
 Tightness
 Discomfort during exercise
 Edema
 Cyanosis
2. Increased venous pattern
 Swelling
 Feeling of heaviness
 Easily fatigued arm and hand
 Superficial vein distension
 Thrombophlebitis of the upper limb
 Tenderness over the axillary vein ,Gangrene rarely
 Venous compression

36. Interscalene triangle Artery , Nerves
VeinCostoclavicular space
Subcoracoid area Artery, Vein , Nerves

37. Arterial TOS
Etiology
 Cervical or anomalous first rib
 Anomalous anterior scalene insertion

38. Symptoms
 Digital or hand ischemia
 Cutaneous ulcerations
 Forearm pain with use
 Pulsatile supraclavicular mass/bruit
 Arterial compression :
 Easily fatigued arms and hands
 Rest pain of hand and fingers
 Paleness – coldness of the hand
 Raynaud’s phenomenon
 Ischemic signs, distal gangrene due to repeated embolization, or to
subclavian artery thrombosis

39. DIAGNOSIS
Clinical maneuvers
Radiography
Ultrasonography
Magnetic resonance (MR) angiography
Computed tomographic (CT) angiography
Angiography and venography

40. Adson maneuver
 Patient is instructed to take and hold a deep breath and extend his neck
fully and then asked to turn his head towards the side being examined.
Obliteration or diminuation in the radial pulse suggest compression.

41. The Roos test
 The patient repeatedly clenches and unclenches the fists while keeping
the arms abducted and externally rotated (palms forward and upward).
The elbows are braced slightly behind the frontal plane for 3mins
 The test is positive when symptoms are reproduced with this maneuver
 A positive test is very suggestive of the thoracic outlet syndrome.

43. Hyperabduction maneuver
 Evaluates compression of the neurovascular bundle between the
coracoid process and the pectoralis minor muscle.
 The patient externally rotates the shoulders and extends the
arms out from the chest and then above the head.

44. Wright's hyperabdution test

45. Halsted's Costoclavicular maneuver
• Evaluates compression of the neurovascular
bundle between the clavicle and the first rib.
• The patient assumes an exaggerated
military position with shoulders pushed
backward and pressed downward.

47. Diagnosis and
Treatment

48. Diagnosis
• “the most accurate diagnosis of TOS…must
rely on a careful history and thorough,
appropriate physical examination”
• No single diagnostic test has sufficient
specificity to prove or exclude the diagnosis

49. DD nTOS
 Carpal tunnel syndrome
 Ulnar nerve compression or neuritis
 Rotator cuff tendinitis
 Cervical spine strain/sprain
 Fibromyositis
 Cervical disk disease
 Cervical arthritis
 Brachial plexus injury

50. DD aTOS
 Other sources of emboli: Cardiac and aortic arch arch causes
 Coagulopathies
 Vasculitis
 Radiation induced arteritis
 Connective tissue Disorders
 Arterial dissection
 Atherosclerotic disease
 Traumatic

51. IMAGING
 X-rays
 Cervical rib
 Elongated C7 transverse process
 Hypoplastic 1st rib
 Callous formation from clavicle or 1st rib fracture
 Pseudoarthrosis of 1st rib
 Unable to image soft tissue anomalies and fibromuscular bands – seen
only at time of surgery

52.  CT/MRI can rule out other pathologies
 Magnetic resonance (MR) angiography
 computed tomographic (CT) angiography of the thoracic inlet,
especially with recently devised techniques and protocols, are
noninvasive modalities that provide image quality comparable
to that of angiography and venography

53. • Angiography and venography remain the criterion
standards for the radiologic diagnosis of these conditions, and
they have the added benefit of enabling potential
endovascular treatment.
• MR neurography – newer technology to detect localized nerve
function abnormality

54. • aTOS
– Segmental arterial pressures
– Angiography
• vTOS
– Duplex U/S
– Venography
– Consider bilateral studies
•

55. EMG
 Reduction in NCV and low amplitude motor responses
 Positive results
Confirms the clinical diagnosis
Poor prognosis if true neural damage present
 Negative results
Does not exclude TOS
 Both EMG/NCV have lo sensistivity for TOS

56. Electrophysiology Testing
 Medial antebrachial cutaneous nerve (MAC)
 Lowest branch of inferior trunk of brachial plexus
 More sensitive to compression than other branches
 Higher sensitivity and specificity with EMG/NCS

57. Scalene muscle block
 Most useful when diagnosis is unclear
 Patient in supine position with neck
 hyperextended and turned to opposite side. Lateral border of
sternocledomastoid is palpated andabout 1.5 inches above the clavicle
anterior scalene muscle is palpated
 5- 7ml of plane bupivacaine and 1ml of betamethasone is injected.
 Relief of symptoms ranging from few days to weeks.
 Good relief of symptoms confirms the diagnosis.
 2-3 injections can be given.

58. Treatment
 Conservative management aims to increase the space in the
thoracic outlet area and to relieve compression on the
neurovascular structures.
 Step 1 proper postural changes and correct faulty postures.
 Step 2 manipulate and mobilize and relax 1st rib and clavicular,
scapular, pectoral muscles.
 Step 3 strengthen the shoulder girdle muscles and stretch
scalene muscles

59. Pain control
• Muscle relaxants
• NSAIDS
• Ultrasonography with ionatophorosis
• Transcutaneous electric nerve stimulation.
(TENS)
• Local anesthetic injections.

60. Edema control
• gloves
• Compressive garments
• Elevation of limb
• Active range of motion exercises
• Retrograde massages
• Phonophoresis controls pain and edema

61. Ergonomics
 Work posture related changes
 Relative adjustment of chair height so that forearm restscomfortably and
without shoulders being elevated or depressed.
 Avoid carrying heavy weights on effected side
 Avoid hyperextension of neck and hyperabducting postures

62. PHYSICAL THERAPY
Is the key of T.O.S. treatment
Its purpose :
 open the costo-clavicular space
 fight against physiological shoulders falling attitude
 Has to be progressive, painless, bilateral
 Average duration : 3 to 6 months
 If properly executed : 70 to 90% of good results

63. Exercises
 Involves relaxing shoulder girdle and stretching the scalene and pectoral
muscles.
 Neck : neck side bending exercises neck rotation
 neck flexion exercises
 Shoulder : shrugging of shoulders
 pendulum exercises

64. TREATMENT OF T.O.S.
• PHYSICAL THERAPY (2)
• Muscular relaxation

65. TREATMENT OF T.O.S.
• PHYSICAL THERAPY (3)
• Correct shoulder falling attitude

66. TREATMENT OF T.O.S.
• PHYSICAL THERAPY (4)
• Reinforce muscles that ‘‘open’’ the costo-
clavicular space

67. TREATMENT OF T.O.S.
• PHYSICAL THERAPY (5)
• Respiratory reeducation

68. Treatment nTOS
• Neck stretching
• Posture correction
• Avoid neck traction,
weights, resistance
exercises,
strengthening
exercises

69. •SURGICAL TREATMENT OF T.O.S.
Surgical treatment is indicated:
• after failure of physiotherapy
• in T.O.S. with venous or arterial complications
(thrombosis, aneurysms…)
• in case of nervous compression
• in case of symptomatic cervical rib

70. Surgical decompression

Symptoms persists beyond 2 months of
conservative management.

Associated vascular compression with
poststenotic dialatation.
 Complete occlusion of a large vessel.
 P rogression of neurological
symptoms.
 Nerve conduction velocity < 60m/s

71. • 1strib resection and scalenectomy are
standard procedures for TOS
• 1strib resection is recommended for lower
type TOS
• Scalenectomy is recommended for upper
type TOS
• Best results and less chance of
recurrence with combined 1strib resection
and scalenectomy.

72. Scalenectomy
• Incision :8cms incision, 1.5cm above middle
third of clavicle.
• 80-90% of scalenus anterior muscle and
40-50% of scalenus medius muscle removed.
Protect long thoracic nerve and phrenic nerve.
Complications : neck hematoma, chylus drainge,
dyspnea due to phrenic nerve irritation.

73. 1st rib resection
1. Transaxillary approach
2. Supraclavicular approach
3. Infraclavicular approach
4. Posterior approach.

74. Transaxillary approach ( Roos approach)
• Transverse Incision at the level of third rib just below
the axillary hair line.
– Advantages
• Limited field of operative dissection
• Cosmetically placed incision
• Achieve 1strib resection and anterior scalenectomy
• Removal of anomalous ligaments and fibrous
bands.
• Less blood loss, no muscles are divided.

75. • Incomplete exposure of entire scalene triangle
• Difficulty achieving brachial plexus neurolysis
• Limited if vascular reconstruction is needed
Disadvantages

76. • Supraclavicular approach
– Advantages
• Wide exposure of all anatomic structures
• Permits complete resection of anterior
and middle scalenes as well as brachial
plexus neurolysis.
• Allows resection of cervical ribs and
anomalous 1st ribs
• Vascular reconstruction is possible

77. Infraclavicular approach
• ADVANTAGES
• Ideal for venous and arterial obstruction.
• Venous embolectomy.
• Arterial reconstruction.
• DISADVANTAGES
• Poor view of thoracic outlet.
• Poor excision of posterior part of the rib.

78. Posterior approach
• Advantages
• cervical rib can be easily resected.
• Sympathetectomy can be done
• Disadvantages
• Vascular reconstruction can not be
performed.

79. Thoracoscopic First Rib Resesction
• Three 10mm portal are made
-1st
anterior 3rdICS
-2ndlateral 5th ICS
- 3rdlateral wall of 6thICS
Endoscopic drill is used to dissesct the rib

80. Adjunctive procedures
– Pectoralis minor tenotomy.
– Sympathectomy :

81. Treatment vTOS
• Anticoagulation therapy with heparin and oral
anticoagulants.
• Fibrinolytics
• Catheter-directed thrombolysis.
• Thrombosis is < 3days old : Thrombectomy
• Chronic thrombosis : Venous Bypass

82. Complications
• Nerve injury
bracial plexus injury
Long thoracic nerve of bell
Phrenic nerve
Intercostobrachial nerve.
Vagus and Reccurent laryngeal nerve
Vascular injury
Subclavian vein and artery

83. Thoracic duct injury
• Lymphatic fistula
• Lymphocele
• Chylothorax
Pleural complication
pleural damage
Pneumotharax
Pleural effusion

84. Recurrent nTOS
• Postoperative scarring most common cause.
• Recurrence usually is seen within 3months.
• To minimize scar tissue formation patient is
instructed to perform active range of motion
exercises beginning the day after surgery.
Performed every 3-4 hrs for atleast 6 months.