• neurological & vascular symptoms & signs in the upper limbs
  • produced by compression of the lower trunk of the brachial plexus & subclavian vessels between the clavicle & the most proximal rib


  • both the subclavian artery and the brachial plexus traverse between the anterior & middle scaleni muscles
  • base of the triangle is the 1st rib
  • even under N circumstances these NV structures bend acutely when the arm rest at the side
  • an extra rib (cervical rib) or fibrous equivalent, anomalous scalene muscle sharpens the angle
  • in some cases, thoracic outlet syndrome will be accentuated by recurrent anterior shoulder instability, and this may be the cause of the “dead arm syndrome”




  • anomalies are all congenital
  • yet symptoms are rare before the age of 3O
  • with declining youth, the shoulders sag, increasing the bend of the NV bundle
  • indeed drooping shoulders alone may cause the syndrome

Clinical features

  • no general symptoms or neck symptoms
  • usually a female in her 30, may complain of


  • pain and/or paraesthesia in the ulnar forearm & hand
  • worse after household chores or after carrying shopping
  • weakness or clumsiness
  • excessive sweating, or blueness & coldness of the fingers
  • a female, the patient is often long-necked with sloping shoulders (like a Modigliani painting)
  • if a male, he is more likely to be thick-necked and muscular


  • lump (the abnormally elevated subclavian artery) may be palpable above the clavicle
    • pulsates, tender and pressure on it may increase symptoms
  • neurological signs predominate (lower trunk C8, T1 - mostly ulnar N )
    • mild clawing of hands
    • wasting of the interosseous and hypothenar muscles
    • weakness of the intrinsics
    • reflexes are usually normal
    • sensation may be diminished in the C8 and T1 distribution
  • vascular signs are uncommon
    • may be cyanosis and increased sweating

Special tests

  • used for pulse obliteration or provoke symptoms
  • Roos test
  • pulse fades when the arm is elevated to 90 degrees and externally rotated while the neck is turned to the opposite side
  • in another the same effect is produced by pulling the arm downwards and backwards while pushing the neck away

Neck and shoulder

  • movements are normal
  • excluding a diagnosis of cervical disc disease or musculo-tendinous cuff disorder


  • may show a 'long' neck - i.e. the first thoracic vertebra stands clear in views of the cervical spine
  • occasionally a well-formed cervical rib, but more often just an enlargement of the transverse process of C7
  • CXR to rule out pancoast tumor

Differential diagnosis

Cervical spine lesions

  • In disc prolapse or spondylosis, pain is more vaguely distributed
  • neck movements are limited
  • in tuberculosis and secondary deposits the x-ray appearance is characteristic

Carpal tunnel syndrome

  • spina bifida occulta 30-70% with isthmic, 40% with dysplastic ~
  • many cases were wrongly called cervical rib syndrome
  • even when x-rays show a rib, the symptoms may still be due to median nerve compression in the carpal tunnel
  • nocturnal pain and its distribution are characteristic

Ulnar tunnel syndrome

  • symptoms and signs are sharply confined to the distribution of the ulnar nerve
  • the neck is unaffected

Pancoast syndrome

  • apical carcinoma of the bronchus may infiltrate the structures at the root of the neck, causing pain, numbness and weakness of the hand
  • hard mass may be palpable in the neck
  • x-ray of the chest shows a characteristic opacity

Spinal cord lesions

  • syringomyelia or other spinal cord lesions may cause wasting of the hand
  • other neurological features establish the diagnosis

Cuff lesions

  • with supraspinatus tendon lesions pain sometimes radiates to the arm and hand
  • shoulder movement is abnormal and painful



  • most patients managed
  • exercises to strengthen the shrugging muscles, postural training and instruction in ways of preventing shoulder droop or muscle fatigue
  • analgesics when necessary

Operative treatment


  • pain severe
  • muscle wasting is obvious
  • vascular disturbances
  • thoracic outlet is decompressed by removing the first rib (or the cervical rib)
  • best accomplished by the transaxillary approach, but care must be taken to prevent injury to the brachial plexus and subclavian vessels, or perforation of the pleura (Roos, 1966)

Natural history of lumbar disc disease

  • natural history of the disc sy. is towards resolution
    • Holmes & Rothman - 90% resolve spontaneously within 3 months</li
    • Singer - similar findings
    • Weber (Spine 1983) - results of disc dx treated operatively at 1 year was far better than those treated non-operatively BUT, at 4 & 10 year follow-up, the results were the same
  • neurological results improved just as well in the conservatively treated group as the operative group
  • natural course of herniated discs - decrease in size (serial CT scans) - Thelander & others

Theory of spinal degeneration

  • all spines degenerate
  • present methods of treatment are for symptomatic relief, not for a cure
  • degenerative process divided into three separate stages

1st stage - dysfunction

  • age group - 15-45 years
  • tears in the disc anulus & localized synovitis of the facet joints
  • familial predisposition to lumbar disc herniation in patients who had herniation before age 21 years

2nd stage - instability

  • 35-70-year-old patients
  • internal disruption of the disc progressive disc resorption, degeneration of the facet joints with capsular laxity, subluxation & joint erosion

Final stage - stabilization

  • patients older than 60 years
  • development of hypertrophic bone about the disc and facet joints
  • leads to segmental stiffening or frank ankylosis
  • each spinal segment degenerates at a different rate
  • one level is in dysfunction, another may be entering stabilization stage
  • disc herniation a complication of disc degeneration in dysfunction & instability stages
  • spinal stenosis from degenerative arthritis is a complication of bony overgrowth compromising neural tissue in the late instability & early stabilization stages
  • males were found to have more degeneration than females
  • L4-5 & L3-4 disc levels showed the greatest degree of disc degeneration

Pain transmitting structures

  • at the level of the intervertebral foramen is the dorsal root ganglion
  • distal to the ganglion three distinct branches arise from the dorsal root

Ventral ramus

  • supplies all structures ventral to the neural canal

Sinu-vertebral nerve

  • originates from the ventral ramus
  • innervating posterior aspect of disc, vertebral bodies & posterior longitudinal ligament

Dorsal ramus

  • three branches
  • innervate the structures dorsal to the neural canal
  • posterior musculature and skin
  • facet joint

Results of surgery

  • failure rate of surgery for pain relief d/t disc herniation is high (reported by several authors)
  • significant morbidity also present post-op

Why surgery often fails

  • main cause of surgical failure = poor patient selection
  • inaccurate diagnosis
  • back pain & sciatica can originate from a number of sites
  • X rays, CT scans & MRI’s are only of relevance if the findings are supported by clinical findings
  • to operate on the basis of special investigations only is unacceptable
  • must also remember:
    • diabetes can mimic a herniated disc
    • ischaemia of the cauda equina & nerve roots are a cause of intermittent claudication
    • psychogenic factors


  • straight x-ray
  • blood tests
  • myelogram
  • CT scan
  • MRI scan
  • bone scan

Special investigations

  • CT & MRI
    • low specificity: 30% of the N population have positive scans which are of no importance
  • EMG
    • has a very high accuracy: helpful test when surgery is considered
  • fibrinolytic activity test
    • a low fibrinolytic response favours a bad surgical result
    • the plasminogen activator inhibitor 1 test is sufficient to assess this
  • discogram
    • valuable pre-operative examination

Treatment modalities

  • manipulation
    • if it has a role
  • traction
    • no proof that it has a beneficial role
  • chemonucleolysis
    • unpopular because of severe complications:
    • transverse myelitis
    • allergic reactions
    • persisting attacks of muscle spasm
  • facet joint infiltration
    • useful, may exclude a facet joint arthropathy as a cause of pain
  • epidural injections (cortisone)
    • recommended
  • spinal corsets
    • have a place in the treatment of low backache

Indications for surgery in discogenic disease

  • all compatible
    • symptom complex
    • clinical signs
    • investigations
  • advanced neuro deficit
  • progressive neuro deficit
  • sphincter involvement
  • incapacitating pain
  • failed conservative management

Lumbar Spinal Stenosis

  • elderly patients
  • smaller than normal spinal canal + spondylosis
  • local pain in back
  • relief by flexion
  • claudication of the cauda equina
  • random neurological signs in legs
  • good surgical outcome

Ankylosing spondylitis

  • young males
  • non-specific “lumbago” symptoms
  • morning stiffness
  • typical radiological signs
  • later signs
    • poker spine
    • respiratory difficulty
    • cardiac and other systems

Non-specific (mechanical) low back pain

  • site
    • discomfort across lower back
    • central pain, usually over L5
    • leg pain or paraesthesia within “sciatic” distribution
    • unilateral or bilateral buttock or lateral back pain
  • character
    • episodic or cyclical pain in the middle years of life
    • arises from L3-S 1
    • early morning stiffness or pain eases when patient is up and about
  • relation to posture
    • often aggravated by sitting or standing still
    • eased by walking normally
  • pain that is greatly aggravated by walking raises the possibility of vascular claudication or spinal or lateral canal stenosis