Thoracic outlet syndrome is caused by compression of the neurovascular structures in the thoracic outlet. It can be caused by abnormalities such as cervical ribs or anomalies of the scalene muscles. Symptoms include pain, numbness, and weakness in the arm. Diagnosis involves clinical exams like Adson's test and imaging tests. Treatment begins with non-operative measures like posture improvement and physical therapy. Surgery to remove compressive structures may be needed if symptoms persist. Recurrence after surgery can occur if all abnormal structures were not removed and may require re-operation using the posterior thoracoplasty approach along with neurolysis and sympathectomy.

1. THORACIC OUTLET SYNDROME

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

3. ANATOMY

Interscalene triangle
− Med : 1st
rib
− Ant : clavicle,
scaleneus anterior
− Post : scaleneus
medius
Costoclavicular
space
− Med : 1st
rib
− Ant : clavicle
− Post : scaleneus
anterior
− Lat : costoclavicular
ligament, subclavius
muscle
 Subcoracoid tunnel
compressed by pectoralis minor tendon, head of
humerus or coracoid process.

6. Subcoracoid tunnel

7. contents

Brachial plexus

Subclavian artery

Subclavian vein

8. Causes

Cervical rib

Long C7 transverse process

Anomalous insertion of scalene muscles

Scalene muscle hypertrophy

Scaleneus minimus

Abnormal bands, ligaments

Fracture clavicle/ 1st
rib

Exostosis

Tumours

Brachial plexus trauma / diseases

9. Cervical rib

A cervical rib is a supernumerary (or extra) rib
which arises from the seventh cervical vertebra.

Sometimes known as "neck ribs"

Congenital abnormality located above the
normal first rib.

A cervical rib is present in only about (0.2%) of
people.

Half unilateral, common in right side.

Usually asymptomatic

10. Types :
1) Completely bony
2) Completely
fibrous
3) Combined
4) Bony swelling

11. 
Type 3 is most common.

Type 3 – a band stretching from C7 vertebra to
Scalene tubercle on 1st
rib. It elevates the
neurovascular bundle compressing it in the
interscalene triangle.

13. Cervical rib

14. Cervical rib

15. Clinical features

Most commonly seen in middle aged women

Usually due to neural compromise.
Interscalene
triangle
Artery , Nerves Scaleneus anticus
syndrome
Costoclavicular
space
Vein Edens syndrome
Subcoracoid area Artery, Vein ,
Nerves
Hyperabduction
syndrome

16. Interscalene triangle

17. Costoclavicular space

18. Hyperabduction syndrome

19. Arterial compromise

Fatigue

Weakness

Coldness

Upper limb claudication

Thrombosis

Paraesthesia

Gangrene

Raynaud's phenomenon due to thrombosis with
distal embolisation

21. Venous compromise

Edema

Venous distension

Collateral formation

Cyanosis

Paget-Schroetter syndrome – effort thrombosis
− "Effort" axillary-subclavian vein thrombosis (Paget-
Schroetter syndrome) is an uncommon deep
venous thrombosis due to repetitive activity of the
upper limbs.

22. Neural compromise

Paraesthesia

Pain in shoulder, arm, forearm and fingers

Occipital headache – referred from tight
scalene muscles

Weakness of forearm, hand.

23. Clinical tests

24. Roos Test

Hold both arms in surrendering position
(90°overhead with shoulders in external
rotation) – reproduction of symptoms within 1
minute . Arm collapses if continued.

modified Roos test / Elevated Arm Stress
Test(EAST)– same as above. Symptoms
precipitated by opening and closing fists
continuously.

25. Elevated arms stress test

26. Adson's (Scalene) Test

Radial pulse diminishes and disappears on
turning chin to same side.

Decreases space between scaleneus anterior
and medius .

27. Adsons test

28. Halsted's costoclavicular
compression test

45° abduction and extension of arm with
downward pressure on shoulders –neck turned
to opposite side- reproduce symptoms

29. Exaggerated military position

Patient shrugs shoulders with deep inhalation
while drawing the shoulders backward in an
exaggerated military position – radial pulse
diminishes.

30. Military position

31. Wright's hyperabduction test

Arm hyperabducted
to 180°-diminishing
radial pulse.

Neurovascular
structures
compressed in
subcoracoid region by
pectoralis minor
tendon, head of
humerus or coracoid
process.

32. Wright's hyperabdution test

33. 
Tinel sign – in supra and infraclavicular region

Phalens sign – in carpel tunnel syndrome
(CTS)

34. Differential diagnoses

Carpel tunnel syndrome

Spinal canal tumors

Shoulder myositis

Angina pectoris

Raynaud's disease

Ulnar nerve compression - epicondylitis

35. Investigations

Chest x ray, cervical spine x ray

MRI, cervical myelography
− r/o narrowing of intrevertebral foramen, disc
compression.

Doppler , vascular
imaging(angiogram/venogram)
− r/o aneurism, thrombosis

Nerve conduction study, electromyography
− confirm neurogenic TOS, localise the area of
compression- r/o CTS

36. 
Double crush syndrome – TOS with other
peripheral sites of nerve compression(CTS)

37. Treatment

38. Non operative treatment

Posture improving exercises.

Breathing exercises.

Avoid aggravating activities.

Avoid repetitive upper extremity mechanical
work and muscular trauma.

Analgesics,muscle relaxants, antidepressants.

Physiotherapy .

39. Surgical treatment
Indications:

Symptoms persists with non operative
treatment.

Associated vascular compression.

Progression of neurological symptoms.

Nerve conduction velocity < 60m/s

40. 
Trans cervical or trans axillary(Roos) resection
of 1st
rib often with release of scalene muscles.

Extraperiosteal excision of Cervical rib(to
prevent its regeneration) .Often a cervical
sympathectomy is also needed.

41. Roos approach

42. 42
F. RECURRENT THORACIC
OUTLET SYNDROME
1. 10% of surgically treated patients have
shoulder, arm or hands pain and pareathesia.
Most patients can be relieved with
physiotherapy and muscle relaxant.
2. In 1.6% of patients, symptoms exacerbate and
persist.
3. Most recurrences occur in 3 months
postoperatively.

43. 43
F. RECURRENT THORACIC
OUTLET SYNDROME
4. Pseudorecurrence
(1) A 2nd
rib was mistakenly resected for
a 1st
rib
(2) A 1st
rib was resected but a cerical
rib was left.
(3) A cervical rib was resected but
an abnormal 1st
rib was left.
(4) A 2nd
rib was resected but a rudimentary 1st
rib was left.

44. 44
F. RECURRENT THORACIC
OUTLET SYNDROME
5. True recurrence
The 1st
rib was not resected completely.
6. All patients with recurrence after 1st
rib
resection should undergo physiotherapy. If
symptoms persist and UNCV is still low
then re-operation is indicated.
7. Re-operation is always done through the
posterior thoracoplasty approach.

45. 45
F. RECURRENT THORACIC
OUTLET SYNDROME
8. The anterior or supraclavicular approach is
not adequate for re-operation.
9. The basic elements for re-operation are
(1) resection of recurrent or persistent bony
remnants
(2) neurolysis of the brachial plexus or
nerve roots
(3) dorsal sympathectomy of T1, T2, T3
ganglia

46. 46
F. RECURRENT THORACIC
OUTLET SYNDROME
10. The technique includes a high thora-
coplasty incision, extending 3 cm
above the angle of the scapula, halfway
between the angle of the scapula and
spinous processes, and caudate 5 cm from
the angle of scapula.
11. The trapezius and rhomboid muscles are
divided..

47. 47
F. RECURRENT THORACIC
OUTLET SYNDROME
12. The scapula is retracted by incision of the
LD muscle over the 4th
rib.
13. The posterior superior serratus muscle
was divided and sacrospinalis muscle is
retracted medially.
14. The 1st
and cervical rib must be resected, if
present subperiosteally.
15. The regenerated periosteum is extirpated.

48. 48
F. RECURRENT THORACIC
OUTLET SYNDROME
16. If excessive scar is present the it is
necessary to perform sympathectomy
initially. This involves resection of a 1-
inch segment of 2nd
rib posteriorly to
locate the sympathetic ganglia.
17. Neurolysis is performed using a nerve
stimulator but not into the sheath.

49. 49
F. RECURRENT THORACIC
OUTLET SYNDROME
18. A J-P drain is left in the area of brachial
plexus. Depo-Medral, 80 mg, is left in the
area of brachial plexus.
19. The arm is kept in sling to be used
gently for 3 months.
20. When the problem is vascular, involving
false or mycotic aneurysms, bypass graft is
interposed. The saphenous vein is usually used.

50. 50
F. RECURRENT THORACIC
OUTLET SYNDROME
21. 7% of patients underwent 2nd re-operation
for rescarring. No death occurred. Only
one patient had infection and needed
drainage.

51. Thank you....