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What is TOS? What is Thoracic Outlet Syndrome? by Dr James Stoxen DC., FSSEMM (hon) FWSSEM

Have you been experiencing headaches, stiff neck, neck pain, chest pain under the collarbone, upper back or shoulder pain, tingling arm or fingers?

Have you been confused about what is wrong and not getting the results you are looking for?

Like many of you, I didn’t know I had thoracic outlet syndrome. Unfortunately, I was misdiagnosed, and mistreated for seven painful years. I later found out I had a severe thoracic outlet syndrome.

If you believe you are getting nowhere being treated for thoracic outlet syndrome, I know how you feel. I suffered from chronic neck pain, chronic upper back pain, constant shoulder pain, arm numbness, and tingling arms and hands, which were misdiagnosed for seven years.

What I was suffering from was a severe bilateral thoracic outlet syndrome.

During that seven-year period, he was a chiropractic student in a top chiropractic college surrounded by teachers who were doctors of chiropractic and experts in chiropractic medicine. He asked for help from everyone, yet, I graduated in chronic pain.

This post is written to ensure you don’t end up suffering as I did.

The thoracic outlet (inlet or compartment) is a tunnel under the shoulder and over the rib cage that allows the safe passage of the artery, vein, and nerves that pass from the chest and neck area into the arm and hand.

First to be able to understand thoracic outlet syndrome you must understand the thoracic outlet syndrome anatomy.

Thoracic Outlet Syndrome Anatomy

What is the thoracic outlet?

The thoracic outlet, inlet, or compartment is a tunnel located under the shoulder and over the rib cage, where the artery, vein, and nerves pass from the chest and neck area into the arm and hand.

So the roof of the tunnel or outlet is the shoulder girdle including the collar bone and the floor of the tunnel is the rib cage,

I call the thoracic tunnel the passageway where the artery, vein, and nerves pass from the outlet over the first rib, over the rib cage, under the collarbone, and under the pectoralis minor into the arm.

Compression of the outlet by the pectoralis minor is sometimes referred to as pectoralis syndrome or neurogenic pectoralis minor syndrome. In reality its really just thoracic outlet syndrome caused by compression of the pectoralis minor and other shoulder muscles.

Where is the thoracic outlet located?

The three Passageways through the tunnel where structures can get compressed

The thoracic outlet allows passage of blood vessels and nerves through three passageways

  1. The Scalene Triangle
  2. The Costoclavicular Space
  3. The Subcoracoid Space

These passageways are what makes up the thoracic outlet or what I call the thoracic tunnel.

The Interscalene Triangle

The muscles which effect the opening or closure of the thoracic outlet or tunnel in the Scalene triangle are the anterior scalene muscle, the middle scalene muscle, the posterior scalene muscle, the subclavius muscle and the first rib. This compression comes from an elevated first rib due to a scalene muscle tension and too much stretching of the scalenes or neck from the side.

Compression of this area is sometimes called a superior thoracic outlet syndrome.  When this area is compressed it can cause scalene muscle symptoms, first rib symptoms such as elevated first rib pain and pain between the neck and collarbone.

The Costoclavicular Space

Costo means ribs and clavicular meaning collarbone so this is the space between the ribs and the collar bone.

The Costoclavicular space is formed by the first, second, and third ribs, the anterior scalene muscle, the middle scalene muscle, the posterior scalene muscle, the subclavius muscle and the first rib. Compression in this area is between the clavicle and first.rib and is sometimes referred to as costoclavicular syndrome.

The symptoms of compression of this area are the typical symptoms of thoracic outlet syndrome plus pain in the lower neck by the collarbone, pain under the collarbone, pain above the collarbone and even tingling in the collarbone area. This is the pain in the upper chest you get when this area is twisted and compressed.

The Subcoracoid Space

The Subcoracoid space includes the muscles that attach at the coracoid process which are the pectoralis minor muscle, the coracobrachialis muscle, the biceps short head muscle, the shoulder girdle and the ribs.

That makes a total of nine thoracic outlet syndrome muscles1 that directly contribute to the compression of the outlet, and one muscle that indirectly contributes to the compression of the outlet and a total of 10 muscles involved in thoracic outlet syndrome that either directly or indirectly contribute to the compression of the thoracic outlet.

What if your thoracic outlet syndrome specialist only focused on three muscles (the anterior scalene muscle, the middle scalene muscle, and the pectoralis minor muscle), thinking this was all that’s needed to decompress your thoracic outlet? Why do surgeons only surgically remove three muscles, when according to every anatomy book there are nine muscles that directly compress the outlet?

Surgeons only remove these three muscles because if they cut out any more, you wouldn’t be able to do the simple activities of everyday life.

They know removing only these three muscles cannot completely decompress your thoracic outlet. Therefore, they know they cannot bring you 100 percent relief, and they aren’t expecting you to be pain free after surgery either.

The Vessels and the Nerves

There are a three important nerves and two important blood vessels that pass through the thoracic tunnel, the subclavian artery which brings oxygenated and nutrient rich blood from the heart pumped into the arm and the subclavian vein which drains the deoxygenated blood out of the arm to the heart.

These are the main areas where the compression takes place.

What are the signs and symptoms of thoracic outlet syndrome?

Compression in different areas leads to different symptoms of thoracic outlet syndrome.

What is vascular thoracic outlet syndrome?

The subclavian artery is what supplies blood to the arm and, if compressed, will not allow oxygen and nutrients to reach your arm. This will cause weakness and the pale color of the arm.  Your hands may feel cold because you don’t have enough oxygen getting to the arm and oxygen allows the cells to breath releasing heat and producing energy.  So your arm could be cold and weaker.

The subclavian vein removes the blood. Subclavian vein compression commonly causes swelling of the arm and hand. Sometimes you have to take photos of both hands and look really close at them in the photo to see the difference in the puffiness.

The nerves that pass through the tunnel start at the spine, combine together to form a bundle called branchial plexus as it passes through the tunnel then they separate out again forming the ulnar nerve, median and radial nerve.   These nerves supply feeling to the arm.

If any area of the brachial plexus or nerves are pinched or compressed or when you have brachial plexus compression you will get inflammation of the brachial plexus where you may feel numbness, tingling, shooting pain or a very sensitive area of skin where that nerve goes.  Most people feel either numbness in the arm or get a feeling of pins and needles. Some doctors specializing in thoracic outlet syndrome even misdiagnose a thoracic outlet syndrome calling it a brachial plexus compression syndrome.

You may feel a sensitivity or deep boring pain in the arm that might be described as shooting, or a different type of deep and achy pain in your arm. With thoracic outlet syndrome the first nerve symptoms start at the ring and pinky finger.  Later it can evolve into numbness and tingling or pain in the other fingers.

These three together form the neurovascular bundle that travels through the thoracic tunnel. If you feel weakness and are frequently dropping things, this means the compression of the much deeper or your artery is compressed not allowing enough oxygen to be supplied to the muscles to allow them to contract. Being unable to open lids and numbness in the arm are also signs of compression deep in the nerve.

Types of Thoracic Outlet Syndrome are not important

There are four types of thoracic outlet syndrome.

  1. Neurogenic thoracic outlet syndrome (Neurogenic TOS), is the compression of nerves.
  2. Venous thoracic outlet syndrome (Venous TOS) is the compression of the vein.
  3. Arterial thoracic outlet syndrome (Arterial TOS) is the compression of the artery.
  4. Disputed TOS is when the symptoms are there, but the cause is unclear.

These are very important to surgeons, but for us, the cause is the same for all four, compression.  This has never been an important way to categorize thoracic outlet syndrome.

I have a better way to categorized TOS types according to your bad habit

We can predict the focus area of the thoracic compression syndrome according to your daily bad habits. If you spend a lot of time leaning back on the couch, in the car with the seatback, leaning at your desk, then your scalenes are straining to hold up your 9-12 pound head. With this bad habit, you are likely to have compression in the interscalene triangle.

If you spend your time working with your hands above your shoulders like a hair dresser, barber, electrician, typing at the computer with your arm exteneded or texting on your phone, then you are likely to have compression of the costoclavicular or subcoracoid space.

If you usually lean your head to the side, lean back on the couch or in bed while talking, texting, typing, browsing, watching youtube, facebook or tik tok videos, had a work or sports accident, you might be having compression in all three areas.

Having the all the muscles of your thoracic outlet anatomy contracting causing your entire upper body to be compressed will make your thoracic outlet syndrome take a lot longer to reverse.

Other Symptoms of Thoracic Outlet Syndrome

Thoracic outlet syndrome has other symptoms from the surrounding area. Because the muscle spasm twists your skull, neck, shoulders, back, and rib cage.  Basically  this is going to lead to headaches or cerebellar thoracic outlet syndrome, a stiff neck, or neck pain. There might also be thoracic back pain symptoms and shoulder pain, sometimes even shortness of breath.

As the compression of the upper body parts may lead to narrowing of the thoracic outlet, this will make you feel numbness in the arms or neck and arm pain syndrome and tingling in the fingertips. This might progress into weakness in the hands; you might be unable to open jars and might drop items frequently.

These symptoms can be in one or both arms. If you feel this in both arms, it is more likely to be thoracic outlet syndrome. In a more extreme case, you might see wasting or arm and hand muscles, hand discoloration, cold fingers and hands, which some refer to as cold arm syndrome and pain and swelling of the arm and hand.

Neck Compression Symptoms

The symptoms of neck compression are a stiff neck, as well as neck pain and headaches. Also, radiating numbness in the cheek, earlobe, shoulder, and outer arm. Some people even experience vertigo and dizziness.

Shoulder Compression Symptoms

Shoulder compression symptoms include stiff and painful shoulder, weakness in the shoulder, pain below the collarbone, and a sharp burning pain between the shoulder blades.

Can thoracic outlet syndrome cause chest pain? Of course!

Upper back and chest compression symptoms

Upper back and chest pain are related to the misalignment of the muscles that attach to the thoracic ribs and cause compression of the rib cage. Some of the other symptoms include tightness in the chest (thoracic tightness), inability to get a full breath, and general difficulty breathing. Crushing chest pain may make you feel like you are having a heart attack.

Nerve Compression Symptoms

The pain can start with pain in the shoulder and tingling in the arm and hand.  In advanced cases of nerve compression, symptoms include weakness in the hand and fingers, which cause a loss of hand dexterity and numbness in the hand or the arm. The progression will lead to muscle weakness and an inability to use the arm.

Vein Compression Symptoms

If the shoulder compresses the outlet, this will compress the subclavian vein. When the vein is compressed, you will notice arm and hand swelling. If rings do not fit due to finger swelling, this might be because of vein compression.

Artery Compression Symptoms (arterial tos symptoms)

If the shoulder or collarbone are compressing the artery, you will feel vascular compression syndrome symptoms which is coldness, white skin, and weakness in the arm and hand with exercise. Those suffering from artery or vein compression will have pain, a tingling arm or numbness in the arms, hands, and shoulders, and the distribution will not match the typical pinched nerve pattern.

Arterial Thoracic Outlet Syndrome Complications

Your hand might feel one arm colder than the other or both arms and hands cold if the compression is on both sides.  The arm can be cool, pale or even bright red. If the pain in your arms feels worse when it’s cold outside, this might mean your artery is compressed.

Other Symptoms of Thoracic Outlet Syndrome in the Surrounding Area

More rare symptoms of complicated thoracic outlet syndrome can be thoracic outlet syndrome vertigo, thoracic outlet syndrome headache, thoracic outlet syndrome and dizziness, thoracic outlet syndrome symptoms dizziness, and thoracic outlet syndrome and breathing problems.

What Is the Cause of Thoracic Outlet Syndrome?

The Mayo Clinic, the Cleveland Clinic, and the National Institute of Neurological Disorders and Stroke, plus the top-10 ranked hospitals for neurology and neurosurgery tell us that compression is what leads to thoracic outlet syndrome

Mayo Clinic

Thoracic outlet syndrome is a group of disorders that occur when blood vessels or nerves in the space between your collarbone and your first rib (thoracic outlet) are compressed (15).

Cleveland Clinic

Thoracic outlet syndrome (TOS) is a term used to describe a group of disorders that occur when there is compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the lower neck and upper chest area (16).

National Institute of Neurological Disorders and Stroke (NINDS)

TOS is an umbrella term that encompasses three related syndromes that involve compression of the nerves, arteries, and veins in the lower neck and upper chest area and cause pain in the arm, shoulder, and neck pain syndrome.

Most thoracic outlet syndrome doctors agree that TOS is caused by compression of the brachial plexus or subclavian vessels as they pass through narrow passageways leading from the base of the neck to the armpit and arm, but there is considerable disagreement about its diagnosis and treatment.

In Chapter 5, I agree that thoracic outlet syndrome is caused by a compression of the blood vessels and nerves as they pass from the chest and neck shoulder arm syndrome.

If your artery is compressed long enough . . . you could end up losing your limb to amputation.

If you have compression of the vein too long or too deep, a clot could form, releasing as an embolus, causing a stroke in your lung. If you think you have a compressed vein or artery, you have to quickly get treatment for your thoracic outlet syndrome.

If the cause of TOS is compression, why can’t we reverse the compression in the head, neck, and shoulder area without surgery? Because the thoracic outlet syndrome protocol most thoracic outlet apecialists use is ineffective at reducing the cause of the compression. In fact, most of them don’t even know what causes it.

Why Thoracic Outlet Syndrome is so hard to manage and diagnose?

Thoracic outlet syndrome is difficult for thoracic outlet syndrome physicians

to manage due to a number of reasons. TOS has nonspecific symptoms as you can have pain in a multitude of areas.

The cause of thoracic outlet syndrome is poorly understood.  Thoracic outlet syndrome physicians know compression is the cause, and you can only have compression where muscles contract. This leads to the belief that muscle tension is the cause, and the treatment is to cut the muscles out. This is the wrong approach as you cannot cut all the muscles out and will leave you still feeling pain in the end.

There is limited applicability of “objective” testing procedures for thoracic tunnel syndrome. Doctors who teats thoracic outlet syndrome should be able to diagnose thoracic outlet syndrome with a simple examination, without the help of scans and pictures, but that is not the case right now.

There could be potential overlap with other clinical disorders of compression such as carpal tunnel syndrome or shoulder rotator cuff strain.

There is a lack of consistently applied criteria for diagnosis and thoracic outlet syndrome treatment for thoracic outlet syndrome. There are 10 tests that can help diagnose it, but none of these can determine the cause of thoracic outlet syndrome.

There are 16 different treatments in practice, but none of these alone, will reverse the compression. These treatments need to be done in a specific combination to address the cause of thoracic outlet syndrome fully.

Lack of treatment due to flawed biomechanics

The success rate for nonsurgical thoracic outlet syndrome treatment physical therapy of thoracic outlet syndrome is not very high, due to thoracic outlet syndrome therapy being based on an outdated medical model of the human anatomy and biomechanics.

Now that you have understood the basic locations and causes of thoracic outlet syndrome, you continue reading to find out exactly how the human body works and how it breaks down and compresses into a chronic state of suffering.

Once you fully understand all the causes and biomechanics of thoracic outlet syndrome, then you will know how to treat thoracic outlet syndrome.

I will also show you the best treatment for thoracic outlet syndrome you can do at home to get the optimum thoracic outlet decompression reverse these compressions and get back into a healthy and pain-free life.

The Human Spring Approach to Thoracic Outlet Syndrome

Thoracic Outlet Syndrome Icd-10 Code Is G54.0

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