Date post: | 23-Jan-2017 |
Category: |
Healthcare |
Upload: | vinita-sharma |
View: | 684 times |
Download: | 0 times |
THORACIC OUTLET SYNDROME
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.
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.
Subcoracoid tunnel
contents
Brachial plexus Subclavian artery Subclavian vein
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
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
Types :1) Completely bony2) Completely
fibrous3) Combined 4) Bony swelling
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.
Cervical rib
Cervical rib
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
Interscalene triangle
Costoclavicular space
Hyperabduction syndrome
Arterial compromise Fatigue Weakness Coldness Upper limb claudication Thrombosis Paraesthesia Gangrene Raynaud's phenomenon due to thrombosis with
distal embolisation
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.
Neural compromise
Paraesthesia Pain in shoulder, arm, forearm and fingers Occipital headache – referred from tight
scalene muscles Weakness of forearm, hand.
Clinical tests
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.
Elevated arms stress test
Adson's (Scalene) Test
Radial pulse diminishes and disappears on turning chin to same side.
Decreases space between scaleneus anterior and medius .
Adsons test
Halsted's costoclavicular compression test
45° abduction and extension of arm with downward pressure on shoulders –neck turned to opposite side- reproduce symptoms
Exaggerated military position
Patient shrugs shoulders with deep inhalation while drawing the shoulders backward in an exaggerated military position – radial pulse diminishes.
Military position
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.
Wright's hyperabdution test
Tinel sign – in supra and infraclavicular region Phalens sign – in carpel tunnel syndrome (CTS)
Differential diagnoses
Carpel tunnel syndrome Spinal canal tumors Shoulder myositis Angina pectoris Raynaud's disease Ulnar nerve compression - epicondylitis
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
Double crush syndrome – TOS with other peripheral sites of nerve compression(CTS)
Treatment
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 .
Surgical treatment
Indications: Symptoms persists with non operative
treatment. Associated vascular compression. Progression of neurological symptoms. Nerve conduction velocity < 60m/s
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.
Roos approach
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
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
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.
F. REC
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
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
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
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
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
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.
Thank you....