Thoracic outlet syndrome

Thoracic outlet syndrome

1. Thoracic Outlet Syndrome

2. ANATOMY OF TOS Boundaries Anteriorly-Manubrium sterni Posteriorly-T1 vertebrae Laterally-1 st rib

3. Contents 1) Subclavian artery 2)Subclavian vein 3)Brachial plexus

4. 3 potential spaces for compression of neurovascular structures 1)Interscalene space-Anteriorly by scalaneus anterior,Posteriorly by scalaneus medius and inferiorly 1 st rib. 2)Costoclavicular space-Anteriorly by clavice and posteriorly by 1 st rib 3)Subpectoralis minor space-Pectoralis minor and costocoracoid membrane.

5. Thoracic Outlet Syndrome Definition:A collection of symptoms that occur due to compression of neurovascular structures between clavice and 1 st rib.(Thoracic outlet Peet introduced this term in 1956. It is usually common in the female sex between 10-50 years of age.

6. Causes 1)Cervical rib
2)Elongated C7 transverse process 3) Exostosis of 1 st rib
4)Fibrous band 5)Post traumatic-Clavicle fracture ,brachial plexus injury
6)Poor posture-Holding head in forward position 7)Muscle abnormalities-Scalaneus muscle hypertrophy, scalaneus minimus

7. Clinical features 1)Neurological 2)Venous 3)Arterial

8. Neurological Neck pain/shoulder pain Tingling, numbness Muscle atrophy

9. Arterial Coldness
Cyanosis Ulcers Gangrene

10. Venous Edema Venous distension Paget Schroetter syndrome-Effort thrombosis of axillary subclavian vein.

11. Clinical tests to diagnose TOS 1)ROOS/EAST test 2)Adsons test 3)Wright’s hyperabduction test 4) Costoclavicular manaeuver 5)Allens test

12. Roos test/East test 90 degree abduction and external rotation of arm. Hold elevation for 3mins and open and close fists. Test is positive if there is pain,parasthesia

13. Adsons test Sitting/Standing position Take deep breath and turn head to affected side Check radial pulse and see for obliteration of radial pulse or presence of bruit infraclavicular.

14. Wright’s hyperabduction test First abduct till 90 and then hyperabduction till 180 degree Diminished radial pulse due to Costoclavicular space compression.

15. Allen’s test Occlude radial artery Clench fist Unclench and continue compression of radial artery If ulnar artery patent, colour returns to normal ,if occlusion pallor present

16. Costoclavicular manaeuver Sitting position Titanic position Shoulders shrugged downwards and backwards and elbow extended palpate radial pulse.If pulse reduces test is positive.

17. Investigations 1)Routine x-rays-Xrays of cervical spine to see for cervical rib, Exostosis, calcifications 2)Chest x-ray 3)Arteriography-Post stenotic dilation 4) Venography-Venous obstruction 5)Nerve conduction studies-To rule out CTS 6)MRI-To see for SOL,disc compression

18. Treatment Non operative 1) Physiotherapy-Breathing and posture strength excercises 2)Pain-Analgesics and muscle relaxants 3)BOTOX A -Binds presynaptically to sites causing neuromuscular Blockade due to decreased release of acetylcholine 4)Avoid repetitive upper extremity work

19. Operative Indications Persistent symptoms progressive neurodeficit Vascular compromise

20. First rib resection and anterior scalenectomy using -Transaxillary approach -Anterior approach -Posterior approach

21. Complications 1)Post stenotic dilatation 2) Reccurent ulcers 3)Gangrene 4) Venous thrombosis