Neurogenic and Nonspecific-type thoracic outlet syndrome – Diagnosis and treatment

Ross Hauser, MD.

As we will see there is much controversy surrounding the diagnosis and treatment of Thoracic Outlet Syndrome including controversies surrounding what doctors consider a successful treatment and what patients consider a successful treatment.

If you are reading this article it is likely that you have been diagnosed with Thoracic outlet syndrome or you have been managing pain in the neck and shoulder area without getting a clear idea of what is wrong with you. Your physical therapist may have suggested to you that you “look up” Thoracic outlet syndrome.

In an October 2021 paper (1) on thoracic outlet syndrome, one that we will discuss below, researchers state:

“The diagnosis and management of arterial thoracic outlet syndrome remain challenging. Patients may present with acute or chronic symptoms of arterial compromise, however, in many patients the constellation of symptoms may reflect concurrent Neurogenic thoracic outlet syndrome and Vascular thoracic outlet syndrome in addition to Arterial thoracic outlet syndrome.”

More commonly diagnosed is the Neurological thoracic outlet syndrome. Here the brachial plexus nerve network of the lower vertebrae area of C5, C6, C7, C8, and upper thoracic T1 is thought to be compressed. The characteristic symptoms of problems with muscle movement and a numb sensation in the shoulder, arm, and hand lead many to this diagnosis. This is a controversial diagnosis as we will see below.

Finally, you may have read about “Disputed thoracic outlet syndrome.” This diagnosis may have caused you the most concern because after years of searching for an answer to your problem, the answer you thought you had, compression of the blood vessels, is something you may not have at all, or at least something that can be identified as truly causing your problems. Why is it disputed? As we will see in the research, some doctors do not believe that thoracic outlet syndrome is THE actual problem. Some doctors think that thoracic outlet syndrome, rather than being a rare disorder is a much more common disorder.

For you, the reader of this article, this confusion is not helpful, answers are. So let’s find some answers.

What are we seeing in this image? Shoulder instability and of importance in thoracic outlet syndrome is a graphic of the two joints that hold the clavicle in place the acromioclavicular joint and sternoclavicular joints.

Note: In our illustration below we show the bony structures of the shoulder and their four articulations, simply how they move. The circular inserts show three synovial joints – the sternoclavicular joint, the acromioclavicular joint, and the glenohumeral joint – and one bone-muscle-bone articulation – the scapulothoracic joint. Instability in some or all these joints should be examined in cases of thoracic outlet syndrome. As the compression on nerves and blood vessels has implicated the clavicle, instability, and hypermobility of the acromioclavicular joint and sternoclavicular joint.

A brief review of anatomy

What are we seeing in this image?

The caption reads Thoracic outlet syndrome (TOS) locations. TOS can occur at the level of the scalene muscles (1), ribs (2), or at the shoulder joint (3).

The thoracic outlet consists of the space between the inferior border of the clavicle and the upper border of the first rib.

The subclavian artery, subclavian vein, and brachial plexus nerves exit the neck region and go into the arm via this space.

In neurogenic or neurological thoracic outlet syndrome, the brachial plexus is compressed, affecting the shoulder, arm, and hand. As this is the most common form of Thoracic Outlet Syndrome, its symptoms can be easily mistaken for other problems.

However, in severe cases of compression of the subclavian vessels, Raynaud’s phenomenon (numbness in the body sometimes associated with Ehlers-Danlos Syndrome), claudication, thrombosis, and edema can occur in the involved extremity.

Thoracic Outlet Syndrome is a legitimate condition and does occur but its prevalence is extremely rare. Most people who come to Caring Medical with the diagnosis of TOS leave with other diagnoses such as glenohumeral ligament sprain, rotator cuff tendinopathy, cervical ligament sprain, or slipping rib syndrome. We discuss this below.

My symptoms are . . .

In your research, you started finding people like yourself suffering from similar symptoms for years. For many, you will see a deep connection between your desk-based computer work and the seemingly endless list of symptoms that a head forward computer posture can cause you. Some of you will identify with people who suffered a whiplash-type injury and suffer from the same problems.

Here is what people tell us about their challenges:

Years of numbness in the shoulder radiating down the arm specifically into the fingers.
Little or diminished grip strength, thumb muscles may be visibly smaller.
Frequent neck spasms or muscle tightness that were not helped by physical therapy, kinesio taping, and neuromuscular re-education exercise.
Pain and discomfort when sleeping. Side sleeping is painful, sleeping on one’s back helps.

My doctors were focus on my thoracic spine

Patients will tell us stories that have many common themes in regard to their severe thoracic pain. One theme would be the focus of their doctors on the thoracic spine. Many have MRIs that show varying degrees of bulging in T1-T2-T3. Many also have MRIs that show cervical spine issues and bulges in their neck from C3-7 with degrees of cervical spinal stenosis. Because conservative care treatment focused on their thoracic pain did not yield results and because of the appearance of cervical stenosis and the suspicion that the patient’s thoracic pain may be from nerve compression, many patients under go cervical stenosis decompression surgery. While many people find good results from this surgery, some do not. For others the surgery made their situation worse.

Is it thoracic outlet syndrome? Our observations in helping patients for over 28 years

In June 2018, in the medical journal Diagnostics, (2) Julie Ann Freischlag of Wake Forest Baptist Medical Center, recapped the challenges facing the doctor and the patient with or thought to have thoracic outlet syndrome:

“Those who diagnose and treat patients with thoracic outlet syndrome, especially those patients with neurogenic thoracic outlet syndrome, have a practice, which needs to include many modalities to diagnose, treat, and intervene to improve their quality of life for the present and for the future. Three key points constitute the mainstay of the art of caring for thoracic outlet patients. Initially, the most important thing is to make an accurate diagnosis. The second most important thing is not to offer interventions that will not help, perhaps harm, and to give false hope to those who have complex symptoms and have had interventions elsewhere without success. The third thing is to develop an algorithm of consistent evaluation and treatment for each patient to ensure an optimal outcome.”

They did not have thoracic outlet syndrome at all

Over the years we have seen many people with the diagnosis of thoracic outlet syndrome. In so many of these people, after we performed a detailed physical examination, we found that they did not have thoracic outlet syndrome at all. We have found thoracic outlet syndrome to be quite rare in this patient group.

When you have true thoracic outlet syndrome, a symptom that is often seen as critical in determining the diagnosis is when the patient raises his or her arm over their head, their pulse drops and numbness envelops the arm. The belief is that the thoracic outlet area, where the nerves and arteries come out of the spinal area near the armpit, is compromised and compressing these vessels and nerves. However, this still may be an indication of a neck related problem and for people who are frequently at the computer.

Another clue that indicates that this is not a thoracic outlet syndrome problem is that when the patient raises his or her arm over their head and numbness envelops the arm, they DO NOT have the numbness sensation in their ring or pinky fingers. They will describe a “numbiness” but when we squeeze their pinky or ring finger, they do feel a pressure sensation, in most cases of thoracic outlet syndrome, they should not. This provides us with a clue that this person does not have a nerve problem, they have a ligament problem. Somewhere along the line, (such as the C6 – C7 area) the ligaments that are holding the vertebrae or shoulder complex in place is weakened and causing hypermobility. This hypermobility can be corrected without surgery. We will discuss this further below.

Despite its low prevalence and incidence, considerable debate exists in the literature on Thoracic Outlet Syndrome

Italian researchers writing in the March 2017 issue of Neurological Science, (3) tried to explain the problems of identifying and diagnosing Thoracic Outlet Syndrome.

“Despite its low prevalence and incidence, considerable debate exists in the literature on Thoracic Outlet Syndrome (TOS). From literature analysis on nerve entrapments, we realized that TOS is the second most commonly published entrapment syndrome in the literature (after carpal tunnel syndrome) and that it is even more reported than ulnar neuropathy at elbow, which, instead, is very frequent.”

In essence, Thoracic Outlet Syndrome gets a lot of publicity in the medical community and these researchers are not sure why because it is somewhat rare.

“Despite the large amount of articles, there is still controversy regarding its classification, clinical picture, diagnostic objective findings, diagnostic modalities, therapeutical strategies and outcomes. While some experts believe that TOS is underrated, overlooked and very frequent, others even doubt its existence as a nosological entity.”

Nosological means to be medical classified, many doctors do not believe Thoracic Outlet Syndrome should be classified as a diagnosis.

Helping doctors identify whether or not a patient has thoracic outlet syndrome

In July 2021, researchers wrote in the World journal of clinical cases (4) covered a lot of ground in trying to help doctors identify whether or not a patient has thoracic outlet syndrome. The doctors suggested to their colleagues that these conditions share many characteristics of thoracic outlet syndrome and should be explored:

Raynaud’s syndrome – Cold fingers, color changes in the skin in response to cold or stress that are relieved by warmth
Vasculitis Severe sudden-onset pain involving more than one limb, elevated C-reactive protein level, skin lesion.
Rotator cuff tear
Cervical radiculopathy
Cubital tunnel syndrome
Guyon’s canal syndrome
Neuralgic amyotrophy: Extreme sudden-onset pain followed by rapid motor weakness and atrophy
Pancoast tumor
Complex regional pain syndrome

They do however suggest that the most frequent cause of thoracic outlet syndrome is brachial plexus compression. If there are objective findings of nerve compression, it is called a true neurogenic thoracic outlet syndrome. However, when there is no specific pathological evidence of thoracic outlet syndrome, it is classified as disputed thoracic outlet syndrome.

Arterial thoracic outlet syndrome

An October 2021 study published in the journal Cardiovascular diagnosis and therapy that I cited at the beginning of this article (1) comes to us from Harvard Medical School. Here the doctors discuss Arterial thoracic outlet syndrome. Here are the leaning points of this paper:

Arterial pathology as the cause of thoracic outlet syndrome is rare, though repetitive overhead arm motion, such as seen in athletes, is a risk factor for developing arterial thoracic outlet syndrome. Symptoms include chronic findings, such as pallor, arm claudication or cool arm.
Occasionally, acute thrombosis can result in limb threatening ischemia (loss of cirulation) requiring emergency medical care.
Outside of acute limb threatening ischemia, management of Arterial thoracic outlet syndrome is variable, however typically begins with conservative measures such as physical therapy. In patients who do not respond or progress on conservative management, surgical decompression may be performed.
Nearly half of patients presenting with Arterial thoracic outlet syndrome have cervical ribs (an extra rib) and around a third have soft tissue anomalies.
Blunt force trauma can result in direct vascular injury or mass effect from displacement of bony structures and resulting hematomas account for nearly 5% of the cases of aTOS.
Iatrogenic causes are possible, particularly in the setting of orthopedic interventions. (The surgery caused it).

Conservative therapy

The researchers point out that conservative therapy for Arterial thoracic outlet syndrome is not well studied due to scarcity of the disease coupled with the problems of making an accurate diagnosis, however, the available data suggest approximately half of patients with thoracic outlet syndrome benefit from at least 6 months of physical therapy with a small subset—around 5%—who actually worsen from physical therapy.

Paget-Schroetter’s Syndrome

Now lets look at a paper from doctors at University of Texas Southwestern Medical Center, published in October 2021 in the journal Cardiovascular diagnosis and therapy (5) offering a summary of Venous thoracic outlet syndrome. (Parenthesis are added to provide simple explanatory notes).

“Venous thoracic outlet syndrome is a spectrum of disease (an umbrella term) caused by external compression of the subclavian vein as it passes through the costoclavicular space. (You have two subclavian veins. One on each side of your body. The subclavian vein’s principle responsibility is to drain blood from the upper extremities and get it back to the lungs and heart so it can be re-oxygenated. The costoclavicular space is the space on the front of your body between the clavicle and the first rib).

Paget-Schroetter’s Syndrome (PSS) or effort thrombosis is a subtype of Venous thoracic outlet syndrome where compression and microtrauma to subclavian vein from repetitive arm movements results in venous thrombosis.

Paget-Schroetter’s Syndrome or effort thrombosis mostly affects young otherwise healthy active individuals, and this further highlights the importance of this condition.”

For Thoracic Outlet Syndrome surgery to work, you must use it on patients who actually have Thoracic Outlet Syndrome

For Thoracic Outlet Syndrome surgery to work, you must use it on patients who actually have Thoracic Outlet Syndrome. Here is a quote from John Hopkins research: “Excellent results were seen in this surgical series of neurogenic, venous, and arterial Thoracic Outlet Syndrome due to appropriate selection of neurogenic patients, use of a standard protocol for venous patients, and expedient intervention in arterial patients.”(6)

However, in new research, specialists offer warnings to their fellow surgeons: “Non-surgical treatment must be attempted as the first line of treatment for all patients with TOS. Many patients respond to this conservative therapy; however, others need surgical treatment.”(7)

Surgical intervention, that is the cutting of structures to give the nerve more room, will not eliminate the symptoms the person is having and could, quite possibly, cause more problems. In fact many surgeons, because of the high complication rate in select patients and limited reports of post-surgical success, as noted, only offer surgery as a last resort.

Back to the cited research:

In the failed operations, pseudo-recurrences (return of symptoms) such as technical errors in the initial surgery may have occurred. Technical errors include a resection of a cervical rib with an abnormal first rib or a resection of the first rib with a cervical rib left in place, associated muscle and tendon damage from the procedure.

Fusion operations supposedly stabilize unstable segments. So if a person gets a fusion operation at say T2-T4, the segments above and below this level are prone to getting advanced degenerative arthritis because all of the movement in this area of the spine have to come from there (because T2-T4 can’t move). For people who have been proposed a thoracic spine surgery option, Prolotherapy should be looked into, we will discuss this below.

More surgical concerns

Doctors at the University of South Florida are trying to solve the very bad problem of postoperative pain management following Thoracic Outlet Decompression.

Writing in the medical journal Annals of vascular surgery (8) the doctors note:

“Thoracic outlet decompression is associated with significant postoperative pain often leading to hospital length of stay out of proportion to the risk profile of the operation.”

In their study the doctors sought to make improvements in hospital length of stay and patient pain control with an improved multiagent pain management regimen.

They examined Thoracic outlet decompression patient records. They looked at hospital length of stay, medication regimen/usage, operative details, and operative indications for all patients undergoing Thoracic outlet decompression from January 2012 through June 2015.

“During early experience, single-agent narcotic therapy was the mainstay of post-operatively pain control. Since 2014, we (the researchers) have adopted a regimen consisting of narcotic patient controlled analgesia, oral narcotics, and scheduled ibuprofen and valium, which is transitioned to oral narcotics/valium upon discharge.
Seventy-four patients were treated with Thoracic outlet decompression over the study period: 36 (49.3%) for neurogenic thoracic outlet syndrome, 23 (31.5%) for venous thoracic outlet syndrome, and 15 (19.2%) for arteriovenous access dysfunction.
Prior to 2014, the mean length of stay was 4 days with a median pain score of 6. Since 2014, the mean length of stay was 2.6 days) with a median pain score of 4.
Since adoption of a multiagent pain management regimen to include scheduled NSAIDs and benzodiazepines, (the researchers) have reduced the mean pain score experienced by our patients as well as the hospital length of stay.

Thoracic Outlet Syndrome Non-Surgical Treatment

Many of the people that we see in our clinics have had a surgical recommendation and are exploring one last option to avoid it. These are people who usually have physically demanding jobs. They tried many years of physical therapy, medications, tapes and braces and anything that they could get their hands on that they thought would bring them relief and their condition worsened. The reason that they do not rush into surgery is the long, maybe six month recovery time. Another concern is that they will not have the strength following surgery to continue with their line of work. This is of course very troubling to someone who is self-employed and in a line of work that requires physical strength.

People end up coming to Caring Medical with a diagnosis of thoracic outlet syndrome looking for relief of their symptoms. After we examine them we found that it is not thoracic outlet syndrome that they have. Thoracic outlet syndrome is rare. It is often the diagnosis given when a patient goes to the doctor and they raise their arm and their pulse drops and/or they will develop numbness down his/her arm. They may also describe symptoms related to the neck, shoulder and elbow.

If you have Thoracic outlet syndrome normally you would get an x-ray or MRI or CT scan to confirm or eliminate an extra rib as the problem.

As you will see in the case history below, a diagnosis of thoracic outlet syndrome is given because there is a belief that nerves in the thoracic outlet that wind their way down to this side of the hand by the little finger and the ring finger are being pinched. But most of the time when people come to see me they don’t have that symptom, they have some odd kind of arm and hand pain with on and off numbness. This is usually a ligament issue that is referring a numbness and pain down the arm. It is the ligaments normally found in the inferior cervical neck area like C6 C7 T1 and shoulder.

So we are looking for shoulder instability causing referral pain down your arm that simulates thoracic outlet syndrome, we are looking for clicking in the neck and neck instability causing numbness down the arm, we are looking at elbow instability causing issues in the fingers and hand.

Recently we saw a patient who carried with her a large stack of medical records. The most common diagnosis she carried from all of the doctors she saw was Thoracic Outlet Syndrome. The patient exhibited some of the classic symptoms including:

Pain in the arm, neck, and shoulder.
She had a tired feeling in her arm, especially doing overhead work.
She experienced some numbness in the ring and little finger that would come and go.

On initial physical examination we demonstrated to her how ligaments in the neck refer pain to the head, hands, and fingers and could cause symptoms that mimic Thoracic Outlet Syndrome. Weakened ligaments allow subluxation of the thoracic spine or subluxation of a rib that attaches to the thoracic spine. The later condition is also known as slipping rib syndrome.

In my opinion, as discussed in the video, a patient can benefit from Prolotherapy to the pain-producing structure(s), Prolotherapy to the neck ligaments, shoulder ligaments and tendons, or to a rib that is slipping.

Typically about six sessions of Prolotherapy are warranted. The thoracic spine often heals slower than other areas of the body because it is never at rest. Even during sleep, the thoracic spine continues to move, so it heals slower even with Prolotherapy. Typically 3 to 6 sessions of Prolotherapy are needed, but for thoracic spine conditions it is more like 5-8 sessions.

Prolotherapy by getting at the root cause of the condition helps eliminate their pain. For those who have spinal cord injury or other signs of nerve irritation surgery may be the only option.

What are we seeing in this image?

The caption reads: Prolotherapy injection sites on anterior thoracic wall. The dots represent painful enthesopathies. The soft tissue attachments of ligament to bone and tendon to bone.

If this article has helped you understand the problems of Thoracic outlet syndrome and you would like to explore Prolotherapy as a possible remedy, ask for help and information from our specialists

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This article was updated November 26, 2021