Thoracic Outlet Syndrome (TOS)
The National Institutes of Health (NIH) describe “Thoracic Outlet Syndrome” (TOS) as 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. Most 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.
Making the diagnosis of TOS even more difficult is that several disorders feature symptoms similar to those of TOS, including rotator cuff injuries, cervical disc disorders, fibromyalgia, multiple sclerosis, complex regional pain syndrome, and tumors of the syrinx or spinal cord. The disorder can sometimes be diagnosed in a physical exam by tenderness in the supraclavicular area, weakness and/or a "pins and needles" feeling when elevating the hands, weakness in the fifth ("little") finger, and paleness in the palm of one or both hands when the individual raises them above the shoulders, with the fingers pointing to the ceiling. Symptoms of TOS vary depending on the type.
Neurogenic TOS has a characteristic sign, called the Gilliatt-Sumner hand, in which there is severe wasting in the fleshy base of the thumb. Other symptoms include paresthesias (pins and needles sensation or numbness) in the fingers and hand, change in hand color, hand coldness, or dull aching pain in the neck, shoulder, and armpit. The nerves that are commonly affected are at the lower part of the neck, the C8 and T1 nerves.
Vascular TOS (which may be arterial, venous, or both) features pallor, a weak or absent pulse in the affected arm, which also may be cool to the touch and appear paler than the unaffected arm. There may be swelling of the extremity. Symptoms may include numbness, tingling, aching, swelling of the extremity and fingers, and weakness of the neck or arm. There may be pain. Headaches may occur.
Common Symptoms of Thoracic Outlet Syndrome
The most common symptoms of TOS are paresthesia in the upper limb (98%), neck pain (88%), trapezius pain (92%), shoulder and/or arm pain (88%), supraclavicular pain (76%), chest pain (72%), occipital headache (76%), and parasthesias in all five fingers (58%), the fourth and fifth fingers only (26%) or the first–third fingers (14%). [Reference: Hooper TL. “Thoracic outlet syndrome: a controversial clinical condition. Part 1: anatomy, and clinical examination/diagnosis.” J Man Manip Ther. 2010 Jun; 18(2): 74–83.]
The symptoms of TOS are usually unilateral (on one side), but sometimes they may be bilateral (both sides).
Causes of Thoracic Outlet Syndrome
Thoracic Outlet Syndrome is essentially a nerve or vascular compression or tension disorder. The cause of TOS is not always known, although if there is an “extra” or cervical rib (as occurs in about 1-2% of the population), that may be a cause. Repeated trauma may also cause TOS. However, much of the time, there does not appear to be an easily identifiable cause for the condition.
Dr. Wladyslaw Ellis, a specialist in TOS, describes causes of TOS to include direct injury, fracture of the collar bone, repetitive work activities, abrupt stretching, occurring in auto accidents with attendant “whiplash,” and often accompanying sudden compression from seat belts. Dr. Ellis points out that repetitive trauma in the current work environment is making TOS “increasingly common.” [Reference: http://www.doctorellis.com/]
Treatment is often conservative rather than surgical. Physical therapy and exercises are often prescribed to help strengthen muscles and relieve pressure on the brachial plexus and on the arteries or veins in the “thoracic outlet,” which is the space between the collar bone and the 1st rib. Anti-inflammatory medications and/or anti-coagulants may be prescribed.
Decompression surgery is performed when required, but symptoms can come back after surgery in many patients within the first two years.
Disability Benefits for Thoracic Outlet Syndrome
Thoracic outlet syndrome is considered a relatively rare disorder that is estimated to occur in < 200,000 US cases per year.
In order to qualify for long-term disability (LTD) benefits under either the Social Security Act (SSA) or an employer-provided group plan (ERISA), you must have detailed medical documentation of your condition and how it affects your ability to work.
A thorough and focused clinical history detailing your symptoms should be accompanied by a detailed musculoskeletal, vascular, and neurological physical examination that includes “provocative” clinical tests, such as the supraclavicular pressure test, Adson's test, elevated arm stress test, Cyriax release test and the upper arm neural tension test.
These tests may help to “objectively” support the diagnosis of thoracic outlet syndrome, but the results of such tests must be interpreted carefully because they are prone to “false positive” results.
Other objective tests that may support a diagnosis include ultrasound scans, venography, plethysmography, angiography, and electromyographic testing of the involved areas. When they are positive (which is not always the case), they may provide important confirmatory evidence of TOS.
Your doctor must also document the functional limitations and restrictions that your condition imposes on you, such as the most that you can lift/carry (e.g., <10 pounds), push/pull, and whether you can reach above your head (e.g., frequently, intermittently, or not at all], and so forth. The more detailed the documentation, the better.
Your disablity lawyer must know how to work closely with your treating physician to get the proper documentation of your specific findings and impairments into the medical records. At Law Med that's what we do.