Overview

Thoracic Outlet Syndrome (TOS) is characterized by the compression of the nerves, arteries, and veins in the thoracic outlet. The thoracic outlet includes the space between the anterior and middle scalene muscles and the dynamic space between the collarbone and the first rib.

Experienced doctors recognize a wide range of thoracic outlet syndrome symptoms, including pain, numbness, tingling, and weakness in the upper limbs. Thoracic outlet syndrome can also reduce blood flow to the arm and hand, precipitating coldness, discoloration, and swelling. To diagnose this condition, a thoracic outlet syndrome specialist may use information from your physical examination, advanced imaging tests, and specialized nerve conduction studies.

In this article, we will discuss five symptoms that should make you think of thoracic outlet syndrome. But before we do that, let us briefly cover the leading causes of this condition.

What are the causes of thoracic outlet syndrome?

Anatomic variations

Anatomic variations in the bones, muscles, and nerves in the thoracic outlet region can increase the risk of thoracic outlet syndrome. Examples include cervical ribs, elongated transverse processes, scoliosis, accessory and variant muscles, and brachial plexus variations.

Repetitive strain injuries

Repetitive overhead activities can cause injury to the soft tissues in the thoracic outlet. This type of injury can lead to chronic pain and discomfort.

Physical trauma

Injuries of the thoracic outlet may result from motor vehicle accidents, falls, or athletic activities.

Pregnancy

Pregnancy causes physiological modifications in the body that increase pressure on the thoracic outlet. The augmentation of fluid, weight gain, and posture adjustments all contribute to this issue.

Occupational causes

Certain occupations that require repetitive overhead movements, prolonged periods of sitting, and prolonged use of vibrating tools, or non-ergonomic computer use are well-documented risk factors for TOS. Construction, manufacturing, and office work all fit into this category.

Athletic activities

Athletes who utilize repetitive overhead motions are at increased risk for developing thoracic outlet syndrome. These motions are seen in swimmers, volleyball players, and baseball pitchers, among others.

What are the five symptoms that should make you think of thoracic outlet syndrome?

Considerable overlap exists between the symptoms of thoracic outlet syndrome and the symptoms of other musculoskeletal conditions that affect the neck and shoulders. Patients with neck and arm pain may find it quite challenging to tell these conditions apart.

However, the positional symptoms seen in thoracic outlet syndrome helps to differentiate it from other common bone and joint disorders. Therefore, if you experience any of these five thoracic outlet syndrome symptoms, especially if you can provoke the pain with your arms in front of you or with your arms over your head, you should speak with a thoracic outlet syndrome specialist.

1. Pain

One of the most common symptoms of TOS is pain in the neck, shoulder, and arm. The pain can be constant or intermittent. Its severity varies from mild to debilitating. You may also notice that the pain radiating down the arms or into the hands.

2. Numbness or tingling

Numbness or tingling in the affected arms, hands, or fingers is another cardinal symptom of TOS. This may occur along with pain or as a separate symptom.

3. Impaired circulation

Compression of the arteries can lead to coldness or paleness of the affected arm or hand. Poor arterial circulation can also cause the hand or arm to feel weak or heavy.

4. Weakness or muscle wasting

In neurogenic thoracic outlet syndrome, compression of the nerves of the brachial plexus can cause weakness or muscle atrophy. Over time, patients may notice that their grip strength is decreasing. Some patients also find it difficult to execute fine motor tasks (e.g., writing, typing on a keyboard, using scissors).

5. Swelling

Venous thoracic outlet syndrome can cause swelling in the hands, fingers, and arms. The veins in the anterior chest wall and shoulder may also become prominent.

You may have noticed that we mentioned separately the venous, arterial, and neurogenic thoracic outlet syndromes. We would like to clarify and emphasize that there are three types of TOS with different causes and distinguishing symptoms.

There are 3 types of thoracic outlet syndrome:

Neurogenic thoracic outlet syndrome

The neurogenic type of thoracic outlet syndrome stems from abnormalities of bony and soft tissues in the lower neck region, as well as dynamic changes on arm motion that compress and irritate the nerves of the brachial plexus.

Symptoms of neurogenic TOS include weakness or numbness of the hand, decreased size of hand muscles, pain, tingling, prickling, numbness, and weakness in the upper body.

Venous thoracic outlet syndrome

The venous type of thoracic outlet syndrome occurs when a person suffers significant compression of the major veins that drain the blood from each arm. As a result of vein compression, the person may experience swelling and blue coloration of the hands, fingers, and arms, as well as heaviness and weakness of the arms.

Arterial thoracic outlet syndrome

Arterial thoracic outlet syndrome is the least common but most serious type of TOS. It may be caused by congenital bony abnormalities in the lower neck and upper chest, such as a cervical rib. Symptoms of arterial thoracic outlet syndrome include coldness and pallor in the arms, hands, and fingers, along with numbness, pain, and poor blood circulation. In severe cases of arterial TOS, there is complete loss of blood flow to a part of the arm. Doctors recognize this as a surgical emergency.

Complications of thoracic outlet syndrome

Chronic pain

Thoracic outlet syndrome can lead to chronic pain in the neck, shoulders, arms, and hands. This will undoubtedly have a negative impact on the person’s quality of life.

Nerve damage

Nerve compression in the thoracic outlet region may cause permanent nerve damage and resultant muscle weakness.

Blood vessel damage

Compressing blood vessels is another consequence of TOS. This may increase the risk of blood clot in the veins or arteries, and arterial aneurysm, seen as a pulsatile mass in the lower neck.

Decreased range of motion

Untreated thoracic outlet syndrome often decreases the range of motion in the neck, shoulders, and arms due to pain, poor posture, and muscle weakness.

Physical and emotional stress

Chronic pain combined with decreased physical function can precipitate physical and emotional stress. Unfortunately, this can lead to personal and professional problems, including depression.

Diminished productivity

TOS can impact an individual’s ability to perform their job, leading to decreased productivity and financial issues.

What is the takeaway message?

Thoracic outlet syndrome is a serious condition that can negatively impact a person’s quality of life if undiagnosed or untreated. Educating yourself about the early signs and symptoms of TOS will allow you to benefit from early diagnosis and treatment by an experienced thoracic outlet syndrome specialist.

We hope that this article helps highlight the cardinal symptoms of thoracic outlet syndrome and informs when a person should suspect this condition.

We answer many people’s questions about thoracic outlet syndrome. Contact us to learn more!

If you have questions about the symptoms of thoracic outlet syndrome, or have been diagnosed with thoracic outlet syndrome, we welcome your thoughts in the comment section below.