Thoracic outlet syndrome describes the symptoms related to compression of any of the thoracic outlet structures. It is a diagnosis of exclusion, meaning that all other possibilities have been exhausted before the diagnosis of “Thoracic outlet syndrome” is made because there is no definitive diagnostic test but rather a collection of symptoms. Why would that be? Any or all structures of the thoracic outlet can be involved, which leads to a wide variety of symptoms associated with thoracic outlet syndrome. Thoracic outlet syndrome is fairly rare, with an incidence of 8% of the entire population. It is more commonly diagnosed in women than men, mostly between the ages of 20 – 50 years old. Women are more susceptible to thoracic outlet syndrome because of the weight and position of breast tissue and the accompanying necessity of supportive underwear. 95 % of cases present with neurogenic thoracic outlet syndrome (NTOS), causing symptoms of nerve compression, like tingling, pins and needles, weakness, and pain. Arterial (ATOS) or venous thoracic outlet syndrome (VTOS) is caused by subclavian artery or vein compression, which causes ischemic arm pain, discoloring, temperature changes, or pain. We are the first line of treatment for thoracic outlet syndrome.

Anatomy of your Thoracic Outlet

The thoracic outlet is the passage of the brachial plexus, subclavian artery, and vein from the neck under the collar bone, over the first rib, and down into the arm. These structures’ journey is not for the claustrophobic, as normal healthy pathways are already fairly cramped.

  • The first passage of the brachial plexus and subclavian artery is through a triangle created by the anterior and middle scalene muscles (front and back) and the first rib at the bottom.
  • The costoclavicular triangle is the second narrow passage, bordered by the first rib, clavicle, and scapula. Here, the subclavian vein joins the subclavian artery and brachial plexus.
  • The third and final narrow passage beneath the coracoid process of the scapula and the pectorals minor muscle insertion.

Safe passage on this epic quest gives you nerve supply and circulation to your entire arm and hand.

Is there a difference between the right and left sides?

Yes, the left and right thoracic outlet differs slightly. The left subclavian artery arises directly from the aortic arch and the right subclavian artery branches off the right common carotid artery. The left subclavian vein travels further and is longer than the right because it runs over and across from the brachiocephalic vein. The left side has a “separate” thoracic duct draining lymph from the left half of your upper body and both lower limbs to the left subclavian vein. The right side lymphatic duct directly connects with the subclavian vein that drains lymph from the right upper quarter of your body only. Thoracic outlet syndrome can happen on one or both sides.

All thoracic vertebral joints have six articulations with neighboring joints, two symphysis with the disc above and below, and four synovial articulations with the articular processes (facet joints), two at the top and two at the bottom of each vertebra. When one team member is stuck or injured, it automatically influences the movement of the rest of the team. The facet joints are angled at 60 degrees in the frontal plane. This encourages rotation and side bending but limits forward and back bending.

Apart from the six articulations mentioned above, your thoracic vertebrae also articulate with the adjoining ribs on the right and left sides. Each rib has two joints with the vertebra it joins, one at the vertebral body (costovertebral joint) and one at the transverse process (costotransverse joint).

Thoracic nerve roots emerge from under the same vertebrae and innervate the skin and muscles of the dermatome, respiratory, and viscera of the thoracic cavity. T1 and T2 supply innervation to the arm and grip strength, too. The thoracic nerve roots form part of the sympathetic chain of the autonomic nervous system, which governs the fight-or-flight response, elevating the heart rate and increasing your breathing rate. So, it’s understandable that thoracic outlet syndrome causes such odd fallout.

What does it do?

The thoracic outlet is a protective gateway for the essential structures that supply your arm and hands with circulation and nerves. It forms a tunnel for the safe passage of these critical structures. Unlike a tunnel through a mountain, which is best rigid, we need movement and flexibility to adapt to different positions. The tunnel must remain open when you hang or rock climb, do overhead lifts or handstands. Many other bones, joints, ligaments, and muscles work harmoniously to keep the tunnel stable but moveable.

What happens to cause Thoracic Outlet Syndrome?

Neurogenic Thoracic Outlet Syndrome is most commonly diagnosed in people between the ages of 20 and 50. The working class, hunched over computers, caring for patients, completing detailed art projects, and cyclists are victims of this position, which drastically increases the risk of developing thoracic outlet syndrome. Symptoms initially come and go and are linked to spending much time in one position.

The longer you spend in any position, the more your body takes shortcuts to get you there. As time goes on, you lose what you don’t use. The muscles at the front of your chest shorten and weaken, like your anterior deltoids, pectoralis group, and latissimus dorsi. Nothing in your body ever happens in isolation; when the muscles no longer have the length to go into an upright position or bend backward, the joints get stuck and stiff, too. Circulation decreases when a joint doesn’t move, influencing synovial fluid production. This fluid inside your joints lubricates and feeds the joint surfaces. Like oil can get sticky in appliances, your synovial membrane becomes granulated and fibrotic, too.

The thoracic outlet diameter changes when your joints and muscles no longer allow free movement. Any of the three passages can encroach on the sensitive structures that pass through the narrow space. The compression of an artery or vein is similar to stepping on a hosepipe. The garden that isn’t watered starts to wither. This causes ischemic arm pain and changes in temperature sensation. Compression of the brachial plexus causes neurogenic thoracic outlet syndrome that changes the nerve’s ability to function and causes changes in sensation, pain, weakness, and numbness.

Causes of Thoracic Outlet Syndrome

  • Change in movement habits, new job or hobby
  • Overhead activities like shoulder press exercises, washing/hanging curtains, painting the ceiling, blow drying your hair
  • A previous clavicle or first rib fracture, even if it was long ago
  • Acromioclavicular joint dislocation with damage to costocoracoid ligament, cyclist and rugby players are at greater risk of dislocating the ACJ
  • Repetitive throwing action with hyper abduction and external rotation
  • Hunched over posture with shortening of pectoralis minor muscle
  • Big-breasted or unsupportive underwear
  • Whiplash
  • Overused and thickening of the scalene neck muscles because of lung conditions
  • Poor breathing patterns or breath-holding while doing overhead exercise

Symptoms of Thoracic Outlet Syndrome

Tests that you can do to see if you have thoracic outlet syndrome

Try the following self-test and see if your thoracic outlet is compromised with prolonged overhead activities. This just shows that the nerve, artery, or vein is compressed with that specific movement only.

  • Sit comfortably without back support.
  • Hands resting on your thighs.
  • This is your baseline.
  • Notice what your arm and hands feel regarding tingling, numbness, temperature, and pain.
  • Any change from this baseline may indicate thoracic outlet syndrome.
  • Raise your arms so your hands are shoulder height, palms facing down.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Raise your arms overhead so that your arms form a “Y”.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Raise your arms sideways in line with your shoulder, palms facing down.
  • Hold this position for 1 min
  • Notice any change in tingling, numbness, temperature, and pain
  • Bend your elbows to 90 degrees and lift your arms so that elbows align with shoulders, palms facing forward.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Place your hands on opposite shoulders, like you are hugging yourself.
  • Lift your shoulder upwards, shrug your shoulder, bringing your shoulder towards your ears.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Take your hands behind your back, lower than your shoulders, palms facing down.
  • Mimic the pose of a siren on the front of a pirate ship by leaning forward slightly.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Take one arm to the “hands up” position.
  • Turn your head to look away from that hand.
  • Bend your neck away from the raised arm.
  • Hold this position for 1 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Put your arms in the ‘hands up’ position, and then
  • Open and close your fists rapidly
  • Continue doing this for 3 min.
  • Notice any change in tingling, numbness, temperature, and pain.
  • Unable to finish due to pain is an indicator of neurogenic thoracic outlet syndrome.
  • Tingling or numbness during this movement may indicate thoracic outlet syndrome.

How severe is neurogenic thoracic outlet syndrome?

Nerve pain is similar to a toothache. Because your nerves protect you, signals from injury or compression are serious. To avoid the risk of long-term nerve damage or neuropathy, it is best to get treatment immediately. Not only will this ease your symptoms, but it will also give you peace of mind.

Any information from your nerves is better than no information, even if the messages you receive are painful. We want to treat and relieve symptoms to avoid the nervous system triggering the alarm of chronic pain. The safer your nerves feel, the more movement they will allow. Pain and tingling indicate a better prognosis than weakness and numbness. Symptoms that occur only after specific positions or movements or that get better with rest are easier to treat. Constant high-intensity pain not relieved by position change is more severe.

Venous symptoms from subclavian vein compression cause a white-blueish appearance of fingers and hands, a cold feeling over your hands, and swelling of the entire upper limb.

Ischaemic arm pain from subclavian artery compression causes pain, tingling, and cramping in the whole arm.

Diagnosis of Thoracic Outlet Syndrome

Physiotherapy diagnosis

The diagnosis of thoracic outlet is a diagnosis of exclusion, which means there are no validated clinical criteria to confirm the diagnosis. Someone with thoracic outlet has mostly seen, tried, and tested numerous other treatments without success because the cause of the symptoms has not been addressed. Our physiotherapist has years of clinical experience, is trained in anatomy, understands biomechanics, and can test the integrity of your brachial plexus nerves and circulation in different positions, the strength and endurance of your muscles, and the mobility of your first rib, clavicle, shoulder, neck, and thoracic spine. We can determine what is causing the symptoms and what is contributing to the symptoms.

That’s why our physiotherapists are the best at diagnosing thoracic outlet, whether it’s true, neurogenic, or ischaemic. 


The first imaging investigation is X-rays of the cervical spine and chest. Skeletal abnormalities, including cervical rib, exostosis, callus formation, bony spur, or calcified fibrous ligament, can be seen on a plain radiograph. This lets us see if something is wrong with the bones’ structure.

Your physiotherapist can refer you to get x-rays taken if necessary.

Diagnostic ultrasound

A Doppler ultrasound determines blood flow through vessels and may be useful in excluding another cause of claudication. It also confirms the diagnosis of compression of the brachial plexus. Ultrasonography is very useful in diagnosing axillary or subclavian vein thrombosis.

If you need an ultrasound, your physio will refer you.


CT allows specialists to see the multi-directional areas of the thoracic inlet and outlet to assess compression of both the artery and the vein. CT images can be manipulated to show the required length of the vessel on a single image, or combined with three-dimensional reconstructions to assist with surgical planning.


MRI and MRA allow dynamic assessment of the thoracic outlet. Contrast MRI images where the before and after are compared when the arms are raised versus when the arms are lowered.  This imaging technique gives us excellent soft tissue resolution to be able to clearly see the changes occurring.

Why is my ischaemic arm pain not going away?

Thoracic outlet syndrome is diagnosed when all other structures have been cleared, which may take months or even years. That already qualifies as chronic pain. You can get stuck in a cycle of pain and worry, not knowing if and how it is safe to move. This creates compensatory patterns and weakness, avoiding social events and stealing from your life.

The underlying structural problem will not blow over and get better by itself; it needs vigorous testing in various positions, even from different medical specialties, because it involves vascular, nerve, muscles, and many other structures each professional is trained to screen. Only after trial and error, from despair, there is hope to ultimately recover from thoracic outlet pain. Every failed treatment is one step closer for us to conclude this rare and complex problem.

Get the proper diagnosis to get the right care and avoid the risk of permanent damage to your nerves and circulation. If you don’t use it, you lose it. We can help you identify contributing factors and change your movement patterns to decrease your symptoms and get you back to what you love doing.

What NOT to do

  • Continuous use of medication that may mask the symptoms.

  • Manage the pain by only taking pain medication.

  • Stretch or train through the pain

  • Leave it untreated, if you are uncertain of the diagnosis, rather call us and be safe

  • Follow online advice from an unqualified individual.

  • Believe everything you read.

What you SHOULD do

  • Give yourself peace of mind by talking to a professional.

  • Avoid activities that are flaring up your pain, like overhead and heavy lifting.

  • Make an appointment to confirm the diagnosis and determine how severe the damage is.

  • Finish your treatment and rehabilitation programme for better long-term results.

Making it worse

  • Overhead activities

  • Reaching behind you in the car

  • Lifting heavy loads

  • Driving

  • Working hunched over at your computer

  • Resting/reading with too many pillows

  • Hanging or leaning on a table or trellis.

Problems we see when patients come to us with Thoracic Outlet Syndrome

Unrealistic expectation of the treatment: If you have had neurogenic or vascular symptoms for months, you’ll need a few weeks of treatment to decrease them. Be patient and consistent with your sessions, and tell your physiotherapist about your frustrations. Treatment is a process that takes time for adaptation to be sustained.

Medication only masks the pain but doesn’t address the root of the problem. One medication might help with one component while exacerbating another. This can make the diagnostic process so frustrating for many patients. Their main concern is the numbness, while treatment over the nerve might make the pain even worse without changing the numbness.

The longer you wait and hope it goes away, the higher your risk of developing chronic pain and avoiding more dangerous vascular complications like subclavian thrombosis or subclavian arterial aneurysm.

Abondoing treatment—Trying out but not completing different forms of treatment is like experimenting with different shampoos every week; you won’t know if or what works. The medical process of elimination is lengthy and sometimes painfully frustrating. Stay the course, and your practitioner is bound to turn the page to rare conditions like thoracic outlet syndrome.

Wearing a brace to ‘support’ your neck or shoulder should not be done for more than a week; it causes stiffness and weakness in the long run, which is very difficult to regain once lost. Swollen arm? Then let it drain, but don’t put it in a brace for days; this may make it even worse, causing pitted edema and poor circulation to your hands and fingers.

Physiotherapy treatment for thoracic outlet syndrome

As a sommelier accurately identifies the grape variety and the conditions in which it was grown to make the glass of wine, our physiotherapists have studied and worked intensively. They know anatomy, physiology, and how biomechanics influences the function and integrity of the tissue they treat. You can count on us to diagnose the root cause of your problem, treat your symptoms and their origin, and get you back to what you love doing.

Even with a complex diagnosis like thoracic outlet syndrome, we may not have the surgical precision to release the pressure on the nerves, arteries, and veins. Still, we can screen and clear all the muscles and nerves in the area to confirm your suspicion or refer you to our network of neuro- and orthopedic or vascular surgeons who specialize in thoracic outlet syndrome.

Our treatment for thoracic outlet syndrome is goal-oriented to ensure we’re achieving the small incremental improvements that a pathology like this requires. Physiotherapists provide guidance and answers with strict guidelines that help with recovery while we implement an effective and structured plan of action. You will discuss the treatment expectations and explain as conditions change.

First, we focus on nerve motion and sensitivity and then progress to motor nerve function, assessing the brachial plexus’s various cutaneous nerves and motor branches. Later, our focus shifts to fine motor coordination, muscle firing patterns, breaking down compensation, and neuromuscular control. Stability and joint range of motion are obvious improvements that are noticeable from day one. Our aim with treatment for thoracic outlet syndrome is to give you symptom relief and gradual strengthening of your neck and shoulder girdle while optimizing movement control.

Phases of rehabilitation for thoracic outlet syndrome treatment

Initial Phase: Symptom management (weeks 1-8)

The duration of this phase of your treatment depends on how long you have had your symptoms. We aim to give you strategies to decrease your symptoms by identifying which positions contribute to your problem. Treatment includes neural mobilizations to get the nerve to slide over or around the obstacle and combined with soft tissue release of scalene, pectoralis minor, and subclavius muscles to allow free motion of the nerve and vascular structures around them.

Deep cervical and cervicopectoral fascia techniques release the restrictions in the fascia layers to allow room for the expansion of the soft tissue. Joint mobilizations of the cervical and thoracic spine can alter the forces spanning the neck and thoracic junction. These are usually combined with active deep breathing exercises. Range-of-motion exercises of the shoulder, ribs, neck, and upper back are crucial to regain normal neutral spinal loading.

Isolated stretching and postural strapping are needed in the initial phases of recovery. Our practitioners use a process of elimination to control the healing environment while still keeping you active by checking your desk setup and exercise routine.

You may need to rest from aggravating activities and adjust your exercise load. To move to the next phase of treatment, we want you to be aware of triggering positions, improve desk/work ergonomics, and increase your pectoralis muscle range. There must be some range of motion to “open” some space for the thoracic outlet. Your upper limb neural mobilizations give you pain relief rather than a flare-up.

Middle Phase: Addressing the contributing factors (weeks 8 – 12)

Now, the fun begins! With your newfound body awareness, a better understanding of what influences your symptoms, and an improved range of motion, we can strengthen your stabilizer muscles for better posture and mobilizers for better endurance. Your thoracic outlet syndrome treatments are spaced further apart so your muscles can adapt to the loading program. You can expect a lot of reps, sets, and therabands during this phase of your rehabilitation. We aim to teach you better movement patterns to prevent your symptoms from returning in the future. If that isn’t part of your training routine, you don’t need to be a gym member or start lifting weights. We can work with what you can access.

Before moving on to the final phase of your treatment, you should be able to keep your hands in the hands-up position for 30 seconds before the symptoms start. By now you should be able to successfully complete the Roos’ test for 1 minute.

Final Phase: Return to overhead load (weeks 12 – 16)

Our aim during the final phase of your treatment is to reintroduce previous symptom-provoking activities with new and improved movement patterns. This includes overhead activities and lifting. During this phase of your thoracic outlet syndrome treatment, we want you to return to your training and activities without needing strapping to encourage good posture. Your strength and endurance should allow you to get back to your life. The nerve and vascular structures can move independently from the surrounding bone and soft tissue interfaces without causing a flare-up.

Healing time for Thoracic Outlet syndrome

Neurogenic pain is infamous for its intensity, attack latency (it makes you pay later), and overall healing duration. Be patient, celebrate the small wins, and stay consistent with your treatment. It may take up to six months to improve your symptoms.

It would be best if you had physiotherapy treatment twice a week for the first two weeks. After this, your treatment sessions are spaced to allow the muscles to strengthen between sessions. This ranges from once a week to once in two-week sessions. How fast you recover will be up to you.

Other forms of neurogenic thoracic outlet syndrome treatment

  • Your doctor (GP) will probably prescribe oral analgesics, gabapentin or pregabalin, and anti-inflammatories to decrease pain intensity.
  • Getting your neck manipulated or ‘clicked’ will not change the space of your thoracic outlet. It could even worsen or trigger a muscle spasm.
  • A biokineticist can help you in the final stages of your rehabilitation and get you back to training for your sport.
  • Wearing a neck brace or arm sling won’t solve your problem. Because it doesn’t change the space of your thoracic outlet, it can lead to muscle weakness and overall stiffness in the long run.
  • Collagen supplements won’t make a difference to your symptoms.
  • Injections, like cortisone or analgesics, may offer short-term pain relief but influence tissue integrity in the long run.

Is surgery a treatment option for Thoracic Outlet Syndrome?

Surgical intervention will only be considered after the failure of conservative treatment, and in some cases, it may be the only option. The right surgical approach must be chosen to treat the structures causing your symptoms. Surgical options for thoracic outlet syndrome include:

  • A rib resection can be performed by a cardiothoracic surgeon to increase the space for the trio of nerve plexus, artery, and vein.
  • A balloon angioplasty and venoplasty are performed by a vasculature surgeon. In these procedures, a balloon is placed in the artery or vein to ensure that circulation is preserved.
  • Splenectomy is performed where the scalene muscles are removed.

All three surgical options carry risks because of the delicate nature of the structures. Risks include permanent nerve damage and lung collapse. After surgical intervention, you need to make specific adaptations to your exercise and everyday routine to protect the area if rib resection or splenectomy is done. Remember, it is not a quick fix and requires rehabilitation as part of your aftercare.

What else could it be?

Arm pain in a specific pattern with weakness or sensory loss on myotome testing and a history of neck pain or injury.

Specific weakness, pain, and paresthesia of the thumb, index, and middle finger that worsens with wrist movements.

Pain is felt with specific movements of the shoulder joint, like lifting bedding or pulling up pants, and it rarely radiates below the elbow.

Pain is more concentrated on the chest wall and ribs and worsens with deep breathing and coughing.

  • Sinister pathology

Cardiac disease or a Pancoast tumor may compress on the thoracic outlet. Rapid, unplanned weight loss, night pain, sweating, and heart fluttering will accompany your arm pain and weakness.

Also known as

  • T4 syndrome
  • Neurogenic Thoracic Outlet Syndrome (NTOS)
  • Arterial Thoracic Outlet Syndrome (ATOS)
  • Venous Thoracic Outlet Syndrome (VTOS)
  • arm nerve pain
  • ischaemic arm pain