Jodi Gerdes, MD Assistant Professor of Clinical Surgery

1. Jodi Gerdes, MD Assistant Professor of Clinical Surgery Louisiana State University Health Science Center October 11, 2012 Thoracic Outlet Syndrome

2. LSU School of Medicine-New Orleans (LSUSOM-NO) is the provider of Continuing Medical Education for this activity. The planning and presentation of all LSUSOM-NO activities ensure balance, independence, objectivity and scientific rigor. The LSU School of Medicine-New Orleans designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit(s) ™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

3. Disclosure Dr. Jodi Gerdes I do not have any commercial interests. A commercial interest is any entity producing, marketing, re-selling, or distributing health care goods or services consumed by, or used on, patients.

4. Objectives • Historical perspectives • Types of thoracic outlet syndrome • Diagnosis and management

5. Historical Perspectives

6. History • Galen – 2nd century – first description of cervical ribs in medical literature • Vesalius – 1543 – Belgian anatomist described cervical ribs • Gruber – 1842 – 4 types of cervical ribs

7. Sir Astley Cooper (1768-1841) • “Prince of Surgery” • Guy’s Hospital in London • President of the Royal College of Surgeons • Suspensory ligaments of Cooper

8. Sir Astley Cooper (1768-1841) • Many contributions to vascular surgery • Pathophysiology of cerebral circulation • Proximal ligation of carotid and external iliac aneurysms • 1821 – woman with pulseless, cold arm and gangrenous changes to fingers • Compression and thrombosis of subclavian artery by a cervical rib

9. History • Coote - 1861 – first cervical rib resection • Paget – 1875 – subclavian vein thrombosis

10. History • William Halsted – 1916 - described how cervical ribs cause subclavian artery post-stenotic dilatation

11. History • Law – 1920 – described congenital bands and ligaments that compressed the lower brachial plexus • Murphy – 1910 – excised normal first rib • Adson and Coffey – 1927 – division of anterior scalene muscle without cervical rib resection • Ochsner, Gage, DeBakey – 1935 – scalene anticus syndrome (Naffziger’s syndrome) – scalenotomy in the absence of cervical rib

12. History • Peet – 1956 – “thoracic outlet syndrome” • Clagett – 1962 – posterior approach to first rib resection • Roos – 1966 – transaxillary first rib resection • Gol – 1968 – infraclavicular approach

13. History • Arteriography and venography introduced in the 1960s for diagnostic purposes • Jebsen – 1968 – nerve conduction studies • Urschel applied to TOS patients • Princeton football player with nTOS

14. Types of Thoracic Outlet Syndrome

15. TOS Combination of anatomic anomalies, physical activities, and life events Constellation of upper extremity symptoms Compression of neurovascular bundle at thoracic outlet Brachial plexus (C5-T1) Subclavian vein Subclavian artery

16. Anatomy • Scalene triangle • Costoclavicular space • Pectoralis minor space

17. Anatomic Variations • Scalene Muscles • Wide vs narrow triangle • Congenital bands/ligaments • Cervical ribs • Incidence 0.74% • Female:male ratio 7:3 • Complete vs incomplete • More common on left • Anomalous 1st ribs • Incidence 0.76% • Equal occurrence in men and women

18. Epidemiology 20-50yo <5% teenagers 10% over 50 Rarely >65 70% female 70% cervical ribs occur in females

19. Types of TOS • nTOS – 95% • Most difficult to diagnose and treat • vTOS – 2-3% • aTOS - <1%

20. Neurogenic TOS Etiology Hyperextension neck injury (whiplash) Repetitive stress injuries (typing, assembly lines) Falls on slippery floors/ice

21. Neurogenic TOS • Predisposing Factors • Scalene muscle anomalies • Narrow scalene triangles • Congenital ligaments/bands • High plexus roots • Cervical ribs

22. Neurogenic TOS • Classification of Congenital Bands and Ligaments within the Scalene Triangle • 1 - Extends from the anterior tip of an incomplete cervical rib to the middle of the first thoracic rib; inserts just posterior to the scalene tubercle on the upper rib surface • 2 - Arises from an elongated C7 transverse process in the absence of a cervical rib and attaches to the first rib just behind the scalene tubercle; associated with extension of the transverse process of C7 beyond the transverse process of T1 on anteroposterior spine radiographs • 3 - Both originates and inserts on the first rib; starts posteriorly near the neck of the rib and inserts anteriorly just behind the scalene tubercle • 4 - Originates from a transverse process along with the middle scalene muscle and runs on the anterior edge of the middle scalene muscle to insert on the first rib; the lower nerve roots of the brachial plexus lie against this band • 5 - Scalene minimus muscle arises with the lower fibers of the anterior scalene muscle, runs parallel to this muscle but passes deep to it to cross behind the subclavian artery and in front of or between the nerve roots, and inserts on the first rib; any fibers passing anterior to or between the plexus but posterior to the artery • 6 - Scalene minimus muscle inserting onto Sibson's fascia over the cupula of the pleura instead of onto the first rib; labeled separately to distinguish its point of insertion • 7 - Fibrous cord running on the anterior surface of the anterior scalene muscle down to the first rib and attaching to the costochondral junction or sternum; lies immediately behind the subclavian vein, where it may be a cause of partial venous obstruction • 8 - Arises from the middle scalene muscle and runs under the subclavian artery and vein to attach to the costochondral junction • 9 - Web of muscle and fascia filling the inside posterior curve of the first rib and compressing the origin of the T1 nerve root • Adapted from Roos, Am J Surg

23. Neurogenic TOS • Pathophysiology • Neck trauma stretches and tears scalene muscle fibers • Swelling of muscle belly  pain, parathesias, numbness, weakness • Scarring/fibrosis of muscle belly  occipital headaches, muscle spasms

24. Neurogenic TOS • Machleder et al 1986 (UCLA) • Type 1 slow twitch muscle fibers convert to Type II fast twitch fibers following stretch injury in scalene muscles • Convert back after severing the muscle • Sanders et al 1990 • >2x more connective tissue cells in anterior scalene after trauma

25. Neurogenic TOS • Symptoms • Pain, parathesias, numbness, weakness • Throughout affected hand/arm • Not necessarily localized to peripheral nerve distribution • Extension to shoulder, neck, upper back not infrequently • “Upper plexus” disorders – radial and musculocutaneous nerve distributions • “Lower plexus” disorders – median and ulnar nerve distributions

26. Neurogenic TOS • Symptoms • Occipital headaches • Perceived muscle weakness • Actual weakness and atrophy are rare • Vasomotor symptoms • Vasospasm, edema, hypersensitivity (CRPS)

27. Neurogenic TOS • Pectoralis minor syndrome • Compression of neurovascular bundle under the pec minor • Pain over anterior chest and axilla • Fewer head/neck symptoms • Consider pec minor tenotomy with thoracic outlet decompression

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

29. Venous TOS • Predisposing Factors • Relationship of vein to subclavius tendon and costoclavicular ligament • Dimensions of costoclavicular space • Repetitive trauma to vein causing fibrosis, stenosis, thrombosis

30. Paget-Schroetter syndrome • Effort thrombosis of axillary-subclavian vein • Associated with TOS in some cases

31. Acute occlusion • Pain • Tightness • Discomfort during exercise • Edema • Cyanosis • Increased venous pattern • Tenderness over the axillary vein • Gangrene (1/23 patients)

32. Physical activities • Lifting or pulling heavy objects, basketball, baseball, painting, tennis, raquetball, football, golf, wrestling, weightlifting, scrubbing, shoveling snow, swinging rifle • Up to 40% had residual symptoms after treatment

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

34. Arterial TOS • Pathophysiology • Arterial compression resulting in post-stenotic dilatation or aneurysm • Distal embolization of thrombus

35. Arterial TOS • Symptoms • Digital or hand ischemia • Cutaneous ulcerations • Forearm pain with use • Pulsatile supraclavicular mass/bruit

36. Diagnosis and Treatment

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

38. History • Neck trauma preceding onset of symptoms • Repetitive stress injury • Occipital headaches • Pain over trapezius, neck, shoulder, chest • Specific disabilities regarding work and daily activities • Exertional arm pain • Other specialists seen and tests/procedures performed

39. Differential Diagnosis nTOS • Carpal tunnel syndrome • Ulnar nerve compression • Rotator cuff tendinitis • Cervical spine strain/sprain • Fibromyositis • Cervical disk disease • Cervical arthritis • Brachial plexus injury

40. Differential Diagnosis aTOS • Other sources of emboli • Cardiac, aortic arch, hypothenar hammer syndrome, coagulopathies • Vasculitis • Radiation-induced arteritis • Connective tissue disorders • Arterial dissection • Atherosclerotic disease • Traumatic

41. Physical Exam • Pulse exam • Listen for bruits • Edema/cyanosis/collateral veins • Tenderness over scalene muscles (trigger points) or pectoralis minor • Reduced sensation to very light touch in fingers • Provocative maneuvers

42. Adson Test • With the patient seated, arms at the sides, the radial pulse is palpated and the examiner listens for bruits above the clavicle • Elevate arm and turn the chin both toward and away from the involved side • A positive test results in diminished radial pulse, bruit, and numbness and tingling • Up to 50% of healthy volunteers have a positive test – unreliable for diagnosis of TOS

43. EAST • Elevated arm stress test • Most accurate clinical test (Roos) • Hold “surrender” position for 3 minutes while opening/closing hands

44. EAST • nTOS • Heaviness, progressive weakness, numbness • Tingling in fingers, progressing up arm • vTOS • Cyanotic arm with distended forearm veins • aTOS • Ischemic, cramping pain

45. Upper Limb Tension Test • Positive response indicates compression of cervical roots or brachial plexus • Negative response is usually adequate to rule out nTOS

46. Imaging • Xrays • 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

47. Imaging • CT/MRI usually negative but can rule out other pathologies • MR neurography – newer technology to detect localized nerve function abnormality

48. Imaging • aTOS • Segmental arterial pressures • Angiography • vTOS • Duplex U/S • Venography • Use positional maneuvers during the studies • Consider bilateral studies

49. EMG/NCS • Reduction in NCV to <85m/s • Positive results • Aid in evaluation of other conditions • Poor prognostic factor if truly nTOS – indicate advanced neural damage • Negative results • Exclude other conditions • May still be nTOS

50. 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 than EMG/NCS