Perioperative management - Thoracic outlet syndrome (TOS) - Left transaxillary first rib resection (TFRR) - Vascular surgery

• TOS = Compression syndromes of the neurovascular bundle at the upper thoracic aperture
• This includes: Shoulder girdle syndrome; costoclavicular syndrome; scalene syndrome; pectoralis minor syndrome; hyperabduction syndrome; Paget-Schroetter syndrome (thoracic inlet syndrome[TIS]); cervical rib syndrome; scalenus minimus syndrome

Type classification

Conservative

• No standard treatment; treatment is tailored to the habitus and symptoms of each patient
• In case of minor complaints, special physiotherapy for several months with building up the shoulder girdle muscles and posture
• Significant improvement not to be expected within 6 months!
• Chiropractic measures are contraindicated!

Surgical

Transaxillary resection/disarticulation of the first rib or first rib + cervical rib in:

• Delayed proximal ulnar and/or median nerve conduction velocity
• Extremely severe nocturnal pain and high analgesic consumption at normal nerve conduction velocities
• Morphological changes of subclavian artery or already clinically manifest peripheral embolization
• Postthrombotic syndrome with confirmed compression of the recanalized subclavian vein as well as the collateral tracts (McCleery syndrome), resulting in considerable complaints
• Conservative treatment that failed or caused deterioration

The indication for transaxillary resection is a topic of controversy among different specialties (vascular thoracic surgeons, neurosurgeons) in the international literature. This is partly due to the different anatomic locations of the compression syndromes and also because of the possible neurologic deficits following brachial plexus injuries. This is why different access routes are also described. The gold standard in Germany, however, is transaxillary resection of the first rib, with 80% of patients becoming asymptomatic postoperatively (conservative treatment 30-40%, depending on the degree of injury).

Surgery aims at complete decompression of the neurovascular bundle to prevent persistent compression and reoperations (the sole root treatment). Surgical access should permit both the treatment of vascular complications, e.g., repair of a subclavian aneurysm, venous thrombectomy, and thoracic sympathectomy in the same setting. With the exception of the pectoralis minor syndrome (= hyperabduction syndrome), all compression syndromes can be treated by resection of the first rib or the first rib + cervical rib.

Stenting should definitely be avoided in TOS/TIS; at most, it can be considered as a bail-out procedure followed by prompt decompression of the upper thoracic aperture.

• Prior radiotherapy

The mean time spent before TOS is finally diagnosed is 4 years!

Medical history

• Broad variety of complaints since compression of the plexus, artery and vein can be concurrent - but to different degrees
• Isolated compression of the plexus, artery, or vein is exceedingly rare (also hard to imagine pathophysiologically), though compression of an anatomic structure may be the leading clinical symptom

1. Complaints due to plexus compression/irritation

• Triggered/aggravated by abduction of and downward traction on the arm
• Pain along the posterior aspect of the shoulder and axilla, radiating to the medial aspect of the arm, elbow, and eventually the 4th and 5th fingers
• Nocturnal tingling, numbness of the arm and pain at rest, especially after more demanding physical activity than normal
• Increased perspiration (due to irritation of the sympathetic fibers)
• Weakness and feeling of heaviness in the affected arm
• Loss of dexterity due to declining coordination of finger movements (objects are dropped or cannot be held anymore)
• Loss of fine motor skills (impaired writing, working with computers, etc.)
• Atrophy of the small muscles of the hand (rather late) 

The mean time spent before TOS is finally diagnosed is 4 years!

Medical history

• Broad variety of complaints since compression of the plexus, artery and vein can be concurrent - but to different degrees
• Isolated compression of the plexus, artery, or vein exceedingly rare (pathophysiologically also hard to imagine), though compression of an anatomic structure may be the leading clinical symptom

1. Complaints due to plexus compression/irritation

• Triggered/aggravated by abduction of and downward traction on the arm
• Pain along the posterior aspect of the shoulder and axilla, radiating to the medial aspect of the arm, elbow, and eventually the 4th and 5th fingers
• Nocturnal tingling, numbness of the arm and pain at rest, especially after more demanding physical activity than normal
• Increased perspiration (due to irritation of the sympathetic fibers)
• Weakness and feeling of heaviness in the affected arm
• Loss of dexterity due to declining coordination of finger movements (objects are dropped or cannot be held anymore)
• Loss of fine motor skills (impaired writing, working with computers, etc.)
• Atrophy of the small muscles of the hand (rather late)

2. Complaints due to arterial compression

• Rapid fatigue, claudication-like complaints during work overhead
• Paleness and coldness of the hand
• Acrocyanosis, also necrosis due to embolic digital artery occlusion (e.g., because of thrombi in a dilated poststenotic subclavian artery or due to subclavian aneurysm)

3. Complaints due to venous compression

• Heaviness and feeling of tension in the affected arm, increasing in intensity during work overhead
• Bulging veins on the hand, upper arm and forearm
• Patients wake up in the morning with a swollen bluish arm

Inspection

• With the patient standing -> postural anomaly?
• Also: scapular winging after compression injury of the long thoracic nerve -> paralysis of the anterior serratus muscle
• Comparison of skin color, skin temperature and perspiration levels
• Increase in circumference and texture
• Increased venous marking
• Trophic disorders, muscle atrophy
• Look for signs of peripheral embolization suggestive of subclavian aneurysm (trash)

Clinical examination

• Gross motor skills when shaking hands and spreading the fingers
• Palpation:
  • Neurovascular bundle often painful on pressure in the axillary and supraclavicular regions
  • Tight trapezius muscle with superior margin painful on pressure
  • Cervical rib may be palpable as a spring-like resistance in the supraclavicular region
• Complete pulse status and vascular auscultation
• Doppler occlusion pressure comparison of the brachial arteries
• Bilateral blood pressure comparison
• (Finger) oscillography

Provocation tests

1. Pulse palpation during elevation and abduction, Apley scratch test

• Pulse loss during elevation and abduction of the arm is meaningful only in the presence of corresponding clinical symptoms
•  According to the literature, asymptomatic loss of pulse is observed in more than 30% of young adults!

2. AER test (Abduction, Elevation, Rotation)

• Suggestive of TOS
• Abduct both arms by 90°, with elbows flexed at right angles, forearm rotated outward (i.e. hands supinated)
• Strong fist clenching exercises in this position for 3 minutes
• Pain and tingling in the fingers, fatigue and feeling of heaviness
• In arterial compression, long lasting painful paleness
• Mostly venous compression manifesting as bulging carpal and brachial veins
• Test is negative in carpal tunnel syndrome, cubital tunnel syndrome and degenerative cervical spine changes

3. Elvey test (upper limb tension test, neurodynamic test)

• 90° abduction of arms and dorsal flexion of hands
• Sensitizing maneuver: Contralateral inclination of head / cervical spine

4. Wright hyperabduction test

• Pulse status of arm abducted up to 180° and rotated outward
• Test is positive in case of pulse loss

Imaging

• Provocation (elevation, retroversion) angiography (e.g. MRI) in TOS with vascular complications
• Provocation venography in TIS
• X-ray of upper thoracic aperture to rule out / confirm cervical ribs
• Chest X-ray in two views to rule out a Pancoast tumor in the differential diagnosis
• Differentiation from degenerative cervical spine syndromes ( X-ray of cervical spine, possibly CT/MRI)  
• Color flow Doppler ultrasonography
• Functional arteriography and venography(in pain-inducing and sitting position)
• Selective arm angiography in peripheral occlusion

Neurologic examination

• Mandatory!
• Measure proximal conduction velocities of ulnar and median nerve
• Absence of delay does not rule out TOS!
• High-grade delay and already evident atrophy of small hand muscles = structural plexus lesion -> poor prognosis

• Standard laboratory panels including blood group
• Mark the affected arm
• Depilation of axilla and, possibly, chest

Vascular complications

• Bleeding, possible need for blood transfusion with risk of infection
• Vascular lesion → repair
• Reocclusion in arterial repair
• Thrombosis of the shoulder girdle / brachial vein
• Systemic reperfusion syndrome with multiorgan failure (rare, depends on muscle mass)
• Local reperfusion syndrome (compartment syndrome)

General surgical complications

• Pleural lesions with hematoma/hydrothorax (temporary chest tube)
• Lymph fistulas, lymph edema
• Impaired wound healing
• Central and peripheral nerve injury: brachial plexus; stellate ganglion with Horner syndrome; phrenic nerve; intercostobrachial nerve; long thoracic nerve with scapular winging
• Chronic ischemia → (minor) amputation