Arm, shoulder and neck pain has a myriad of causes and can be difficult to diagnose. However, there are a few tell-tale signs that might point to thoracic outlet syndrome (TOS). In this article, we look at the types of TOS, its symptoms, and what you can do about it.
Do you have pain, heaviness or tingling in your shoulder, neck or arm? Is it worse when you’re doing something with your arms over your head (think hair drying or reaching those upper shelves)? Perhaps you get sudden pain or tingling when you’re in the car and you reach behind to the back seat? Struggling to find out what the problem is?
Maybe it’s time to consider thoracic outlet syndrome.
Shoulder, neck and arm pain are very common, but figuring out the underlying cause can be tricky. There are many possible triggers that need investigation. This is because this area packs a lot of potentially pain-producing structures. These include the neurovascular structures – that is, the nerves, arteries and veins that serve the arm. Because these must pass through small spaces to reach the arm, they are vulnerable to compression. That’s essentially what’s happening in thoracic outlet syndrome.
Symptoms of thoracic outlet syndrome
TOS is due to compression of the nerves or blood vessels that feed the arm. Nerve compression is the most common. But in some cases, the main vein or arteries of the arm can become compressed. This means you can have nerve- and circulation-related symptoms.
You may feel pain in the shoulder, neck and/or arm. You may also have pain in your chest, armpit, face, head and upper back. Some evidence suggests TOS may even give headaches in the base of the skull.
The pain can be accompanied by tingling or numbness in your arm or hand. Your arm might also feel weak or heavy.
Less commonly, some people also experience swelling or discolouration of their arm, which can turn pale or a bluish colour.
In more advanced cases, there might be muscle wasting. You may see hollows around the shoulder blade or the hand. The affected areas will depend on which structures are being compressed.
Activities that tighten that neurovascular space at the top of the shoulder tend to make symptoms worse. Many people find having their arms above their heads can trigger symptoms – think using a hair dryer or reaching to the top shelves. In the car, reaching to the back seat can have a similar effect. In addition, situations where the arms are pulled down, such as when carrying heavy bags, can also aggravate symptoms.
Three types of thoracic outlet syndrome
TOS can be categorized according to the structures that are being compressed.
Arterial TOS
Arterial TOS is the least common type: of all cases of TOS, only 1% affect the arteries. In this syndrome, as the subclavian or axillary artery pass out of the chest and into the arm, they can become pinched between muscular or bony structures.
This is more likely when someone has bony abnormalities, such as an extra, ‘cervical’, rib. Or, if a previous fracture to the collar bone has left a bony lump.
It can also happen in people who do repetitive activity with their arms above their heads. Weightlifters, swimmers and cricketers are at greater risk, along with decorators and warehouse employees. Statistics show that young men are more likely than others to have arterial TOS.
Sufferers complain of heaviness and weakness in their arm, along with a generalised, deep ache. Symptoms tend to be worse when using the arm and ease with rest. The arm may also be pale, and the skin and nails of the hand can become dry and brittle.
Venous TOS
In a similar way, the subclavian vein is at risk of compression in the small spaces of the chest and shoulder. Venous TOS is slightly more common than the arterial type, accounting for 10–15% of all TOS cases.
It’s characterised by an intense pain of the arm that may spread to the armpit, shoulder, neck and chest. The arm may appear a bluish colour and may swell rapidly. You may see prominent veins in your hand, arm, shoulder or neck.
Arterial and venous TOS can be confirmed using specialist scans that examine blood vessels, such as magnetic resonance angiography.
Neurogenic TOS
This is by far the most common form of thoracic outlet syndrome, accounting for 85–90% of all cases.
It involves compression of a network of nerves called the brachial plexus. Nerve ‘roots’ leave the spine in the neck. They combine to form the brachial plexus in the shoulder, from which then emerge the peripheral nerves that travel into the arm and hand. These nerves provide both sensation and muscle control.
The brachial plexus is at risk of compression in several places. First, the nerves pass through a small, triangular gap between the ‘scalene’ muscles of the neck (A), near where they attach to the top rib. Second, they pass between the collar bone and the top rib (B). Third, they can become entrapped between the upper ribs and the tendon of one of the small chest muscles (the ‘pectoralis minor’) (C).
Neurogenic TOS can produce pain that’s sharp and shooting. You’re also likely to get tingling or even numb areas in your shoulder, arm or hand.
Some people feel a more intense pain and tingling at night. This is usually because there’s a release of the compression. It’s like the pins and needles you get in your feet after sitting on them.
If your doctor suspects neurogenic TOS, you may be sent for nerve conduction tests. However, these can sometimes show normal nerve function, even in cases of TOS. This is because the tests look at function of the large fibres in the nerves, whereas ongoing nerve compression causes degeneration in the small nerve fibres first.
Can osteopathy help TOS?
In many cases, yes. Manual therapy is recommended as the first line of treatment for thoracic outlet syndrome.
If you think you may have thoracic outlet syndrome, check in with your osteopath. They understand the condition and will be able to diagnose it or send you for further tests if necessary. They’ll include nerve tests (including pin-prick and thermal tests to look for small-fibre nerve changes) and orthopaedic tests that can help pick up TOS.
Should your osteopath feel you need an orthopaedic or surgical opinion, they will refer you appropriately.
TOS symptoms can be triggered by anything that impinges on those spaces where nerves and blood vessels pass. That includes muscle spasm or enlargement, trauma, inflammation, and postural issues – all things amenable to osteopathic treatment.
Posture can be a factor because it can change the alignment between the collar bone, upper ribs and shoulder, and the associated muscles and tendons. A successful treatment plan may include strengthening to improve posture, alongside manual therapy to ease muscle tension and improve joint mobility. Your osteopath can also advise on how to modify daily activities to avoid triggering symptoms.
Even in cases where there are bony abnormalities, osteopathy may be able to help. People with cervical ribs, for example, have them from birth. But it will often take another trigger to initiate the TOS. That might be an accident, a new sport, or a change in activity. Your osteopath can help identify these triggers and direct treatment at returning you to your healthy state.
Here at OCHK in Central Hong Kong, we are experienced in the treatment of thoracic outlet syndrome. Our team includes osteopaths, corrective exercise therapists and yoga therapists. Our combined approach offers successful and long-lasting relief from thoracic outlet syndrome. Book in today and get back to health!