Physical Therapy Corner: Thoracic Outlet Syndrome
Thoracic outlet syndrome is actually a collection of syndromes brought about by abnormal compression of the neurovascular bundle by bony, ligamentous or muscular obstacles between the cervical spine and the lower border of the axilla.
What does that mean?
First of all a syndrome is defined as a group of signs and symptoms that collectively characterize or indicate a particular disease or abnormal condition.
- The neurovascular bundle which can suffer compression consists of the brachial plexus plus the C8 and Tl nerve roots and the subclavian artery and vein.
- The brachial plexus is the network of motor and sensory nerves which innervate the arm, the hand, and the region of the shoulder girdle.
- The vascular component of the bundle, the subclavian artery and vein transport blood to and from the arm, the hand, the shoulder girdle and the regions of the neck and head.
The bony, ligamentous, and muscular obstacles all define the cervicoaxillary canal or the thoracic outlet and its course from the base of the neck to the axilla or arm pit. Look at the scheme of this region and it all becomes more easily understood.
What are the signs and symptoms of thoracic outlet syndrome?
It is important to understand that presenting with the symptoms listed below in no way indicates a definitive diagnosis for thoracic outlet syndrome. Professionals understand the importance of coupling diagnostic testing skills with the patients report of what hurts and what doesnt seem to be working properly. Dont self diagnose! Neurologic and vascular symptoms can be indicative of more serious conditions.| Vascular symptoms include: | Neurologic symptoms include: |
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What causes the neurovascular compression?
Compression occurs when the size and shape of the thoracic outlet is altered. The outlet can be altered by exercise, trauma, pregnancy, a congenital anomaly, an exostosis, postural weakness or changes.Below is a list of the component syndromes which comprise thoracic outlet syndrome along with a brief description of each. Refer to the scheme for questions about the gross anatomy of the region.
- Anterior scalene tightness
- Compression of the interscalene space between the anterior and middle scalene muscles-probably from nerve root irritation, spondylosis or facet joint inflammation leading to muscle spasm.
- Costoclavicular approximation
- Compression in the space between the clavicle, the first rib and the muscular and ligamentous structures in the area-probably from postural deficiencies or carrying heavy objects.
- Pectoralis minor tightness
- Compression beneath the tendon of the pectoralis minor under the coracoid process-may result from repetitive movements of the arms above the head (shoulder elevation and hyperabduction).
What sort of activities can cause these compression syndromes?
Thoracic outlet syndrome has been described as occurring in a diverse population. It is most often the result of poor or strenuous posture but can also result from trauma or constant muscle tension in the shoulder girdle.Static postures such as those sustained by assembly line workers, cash register operators, students of, for example, those who do needle work often result in a drooping shoulder and forward head posture. This position of the shoulders and head is also indicative of poor upper body posture. Middle aged and elderly women who suffer from osteoporosis often display this type of posture as a result of increased thoracic spinal kyphosis.
Carrying heavy loads, briefcases and shoulder bags can also lead to neurovascular compression. Humans are not well adapted as beasts of burden and heavy loads hung form the shoulders and arms can stress the supporting structures of the shoulder girdle which is basically suspended by the clavicle and all of the component ligaments and muscles.
Occupations which require repetitive over head arm movements can also produce symptoms of compression . Electricians, painters and plasterers may develop hyperabduction syndrome. Compression of the neurovascular structures also occurs in athletes who repetitively hyperabduct their arms. Swimmers, volleyball players, tennis players and baseball pitchers may suffer compression of the neurovascular structures as well. However, compression of these structures may be caused by stretching or microtrauma (small tears in muscle tissue) to the muscles which support the scapula.
Are there other causes of thoracic outlet syndrome?
Some people are born with an extra rib right above the first rib. Since this intersection of nerves, vessels, muscles, bones and ligaments is already quite involved one can imagine what the presence of an extra rib in the region might do. A fibrous band extends from this cervical rib to the first rib causing an extra bend in the lower part of the brachial plexus which may produce a compression in this region.
How is thoracic outlet syndrome treated?
The first step to beginning any treatment begins with a trip to the doctor. Make a list of all of the symptoms which seem to be present even if the sensations are vague. Make a note of what activities and positions produce or alleviate the symptoms and the time of day when symptoms are worst. Also, note when the symptoms first appeared. This list is important and should also include any questions one may have.Due to overlapping in terms of symptoms its difficult to make a definitive diagnosis; this is why a list is so important. Certain diagnostic tests have been designed which are very useful for examination. These tests involve maneuvers of the arms and head and can help the practitioner by providing information as to the cause of the symptoms and help in designing an approach to treatment. These tests, accompanied by a thorough history help in ruling out other causes which may produce similar symptoms. These include Pancoast tumor, neurofibromas, cervical spondylosis, cervical disk herniation, carpal tunnel syndrome and cubital tunnel syndrome. Dont forget to ask your practitioner about these conditions as well.
Here are a few more commonly applied provocation tests used in the diagnosis of thoracic outlet syndrome. These tests may or may not momentarily reproduce symptoms but as was mentioned earlier are important in ruling out other causes which may produce similar symptoms.
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Conservative treatment usually includes local heat and a program which address postural retraining, shoulder strengthening and stretching exercises. The practitioner will create a treatment program specific to the presenting symptoms. Below are a few self-stretching exercises. All of these exercises should be performed slowly and carefully. Each position is assumed smoothly to the point where a stretch is felt intensely but with no pain. There should be no bouncing in any of these positions. Hold the stretch for 30 seconds and then gently and slowly release it. Wait 10 seconds and repeat the stretch 3-5 times. If the stretches increase the symptoms do not continue.
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These stretches are not cures. They may help in alleviating some of the symptoms of thoracic outlet syndrome but as with any exercise program one should always consult a physician before beginning particularly when symptoms persist for any length of time.
![[Hands-Up Test Image 1]](handsup1.jpg)
![[Hands-Up Test Image 2]](handsup2.jpg)
![[Adson Maneuver Image]](adson.jpg)
![[Costoclavicular Maneuver Image]](costo_man.jpg)
![[Allen Test Image]](allen.jpg)
![[Provocative Elevation Image 1]](prov_elev1.jpg)
![[Provocative Elevation Image 2]](prov_elev2.jpg)
![[Neck (side) Stretch Image 1]](neck1.jpg)
![[Neck (side) Stretch Image 2]](neck2.jpg)
![[Chest Stretch Image 3]](chest3.jpg)
![[Neck Stretch (side) Image]](neck3.jpg)
![[Shoulder-Chest Stretch Image 1]](sh-chest1.jpg)
![[Shoulder-Chest Stretch Image 2]](sh-chest2.jpg)
![[Shoulder-Chest Stretch Image 3]](sh-chest3.jpg)
![[Rib Mobilization Image 1]](rib1.jpg)
![[Rib Mobilization Image 2]](rib2.jpg)