الفهرس 
Anatomy of thoracic outletOnly 14 pages are availabe for public view
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Abstract
Thoracic outlet is a tight anatomical space containing the
neurovascular bundle supplying the upper limb involving the subclavian
artery, vein and the brachial plexus.
There are three narrow anatomical parts of the outlet which are
scalene triangle, costoclavicular triangle, and the subcoracoid space.
Though the subclavian vein is passing anterior to the scalenus anterior
(outside the scalene triangle) it could be entrapped in the remaining other
two narrow spaces which are the costoclavicular and subcoracoid triangles.
The actual pathogenesis of the thoracic outlet syndrome is the result
of the repetitive or continuous compression inflected upon the
neurovascular structures, resulting from the narrow one or more narrow
spaces mentioned before to give the picture of one or more of the following
types of thoracic outlet syndrome:
1) Neurologic thoracic outlet syndrome.
2) Arterial thoracic outlet syndrome.
3) Venous thoracic outlet syndrome.
4) Disputed (non specific) thoracic outlet syndrome.
The diagnosis of the thoracic outlet syndrome is based on:
1) Careful history taking: (trauma, similar diseases ...etc)
2) Complete Neurological and vascular examination.
A number of provocative maneuvers have been proposed for the
clinical diagnosis of thoracic outlet syndrome. All tests make use of
movements that restrict the space through which the neurovascular
bundle pass, these involve:
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Summary and Conclusion
*Morley test.
*wrist-fit test.
*Adson test.
*Roos test.
*Halsted tests.
3) Proper investigations involving:
A – Lab studies. To exclude systemic diseases.
B – Radiological studies: (plain X-rays., U/S, CT exam., MRI.)
C – Neurophysiologic studies. (EMG, NCV, ..etc)
D – Angiographic studies.
The thoracic outlet syndrome is considered as highly controversial
presenting disease which is misdiagnosed with various other differential
conditions :( Cervical radiculopathy, Peripheral nerve compression …etc).
The treatment of the thoracic outlet syndrome is mainly a
conservative one, where it is considered as the mainstay of the management,
these involving: (weight reduction, pain and edema control, education
program, postural correction, physiotherapy ...etc).
The scalene muscle block is used as a diagnostic maneuver as well as
therapeutic one, where the scalenus anterior is paralyzed through intra
muscular Botox injection.
The surgery for the thoracic outlet syndrome is indicated where
Failure of a carefully supervised exercise and postural program, Intractable
resistant pain, Significant neurological deficit, Impending vascular
catastrophe, could occur.
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Summary and Conclusion
The surgical maneuvers are applied to decompress the entrapped
neurovascular bundle through:
Scalenectomy, 1st rib resection, removal of a fibrous band, brachial
plexus neurolysis, and vascular reconstruction.
The surgical approaches are:
*Transaxillary approach,
*supraclavicular approach,
*infraclavicular approach,
*Paraclavicular approach,
* Posterior subscapular approach,
The transaxillary approach is favored by most surgeons, where it
gives good exposure to the first rib through a hidden plastic incision.
The supraclavicular approach is applied to give sufficient view of
the brachial plexus, the two scalene muscles, and even the first rib with
satisfactory access to the vascular elements.
The infraclavicular approach allows adequate exposure of the
subclavian vein and the costoclavicular space.
The Paraclavicular Approach is a combination of supra and
infraclavicular approaches.
The posterior subscapular approach gives good view of brachial
plexus and first rib.
160
Summary and Conclusion
The endoscopic surgery is a new era of thoracic outlet syndrome
treatment; there are two main applicable maneuvers:
1. Port access first rib resection,
2. Endoscopic assessed transaxillary first rib resection.
The surgery for thoracic outlet syndrome may result in some
complications which may be intra, or post operative complications
involving:
1. Pneumothorax.
2. Vascular complications.
3. Nervous complications.
4. Decompression failure.
The urgent interventional procedures are applied to deal with the
urgent vascular problems.
These maneuvers include:
1. Arterial procedures;
It consists of decompression and repair of the arterial lesion,
and management of the associated ischemic problems of the
extremity.
2. Venous procedures:
With the ordinary operative decompression, surgeon could do
transcatheter thrombolytic therapy; Balloon angioplasty and
stenting are added in cases of residual stricture.