Nerve Surgery for Thoracic Outlet Syndrome
What is Thoracic Outlet Syndrome?
Thoracic outlet syndrome (TOS) is a term used to describe compression (pressure) on the nerve (brachial plexus) or vascular structures near the base of the neck and collar bone. It can be further subdivided depending on whether or not the compression primarily affects nerves (neurogenic TOS,) veins (venous TOS), or arteries (arterial TOS). Neurogenic TOS is by far the most common type, accounting for approximately 95% of all cases of thoracic out syndrome. Venous TOS (3-4%) and arterial TOS (1%) occur much less frequently and are usually due to some type of anatomic variation such as a congenital cervical rib, a deformed first rib, or fibrous bands.
Meet Tina – a patient of Dr. Tollestrup’s with Thoracic Outlet Syndrome
What kinds of symptoms does Thoracic Outlet Syndrome produce?
The symptoms associated with TOS depend on which structures are being compressed.
Neurogenic TOS can produce an astonishing variety of different clinical symptoms and signs potentially affecting many different areas including the head, neck, upper back, shoulder girdle, chest, arm and hand. Common symptoms are pain, numbness, tingling, and pins/needles sensation. There if usually some degree of weakness in the affected extremity and patient’s often report that their arm feels “heavy” or that it will fatigue very quickly with repetitive use. Patients with neurogenic TOS tend to avoid carrying anything heavy, either held in the hand or requiring a strap over the affected shoulder, like a purse or backpack. Parascapular pain is another common feature of neurogenic TOS. This is pain that usually starts in the posterior neck area and then radiates down between the spine and the border of the shoulder blade. Neurogenic TOS can produce “headache” pain on the affected side, facial pain, jaw pain, and ear pain. Patients can experience pain over the upper back or shoulder blade posteriorly, as well as chest or breast pain anteriorly. All these symptoms of neurogenic TOS tend to be made worse with any type of repetitive or prolonged use of the affected arm, especially activities requiring the arm to be extended above the patient’s head.
Venous TOS typically presents with abrupt, spontaneous swelling of the entire arm along with pain, heaviness, and a bluish discoloration of the arm.
Arterial TOS usually presents with a sudden onset of pain and weakness in the affected arm, along with numbness or tingling of the hand and fingers. The arm and hand may appear pale and be cold to the touch. Use of the arm can result in rapid fatigue of the muscles or claudication which is pain similar to a muscle cramp.
What causes Thoracic Outlet Syndrome?
Neurogenic TOS is most commonly arises following some type of trauma. Any type of injury mechanism which causes rapid widening of the angle between the neck and shoulder, whiplash-type injuries to the neck, blunt trauma to the base of the neck/collar bone area, or traction to the arm can lead to neurogenic TOS. These types of injuries commonly occur during automobile or motorcycle accidents, falling onto an outstretched arm, or anything that forcefully pulls on or causes the arm to be stretched. Sometimes repetitive stress (performing the same motion over and over again) in a workplace setting can also lead to neurogenic TOS.
These types of injury mechanisms can cause trauma to the scalene muscles or the brachial plexus (nerves) itself. Damage to these structures can produce bleeding, swelling, and subsequent scarring and contracture or shrinking of the tissue around the nerves leading to compression and tethering. Ultimately this leaves the brachial plexus in a condition where it is under pressure and unable to glide or move through the surrounding tissue like it’s supposed to.
The presence of a cervical rib, congenital or acquired deformity of the first rib, or unusual fibrous bands or configurations of the anterior and middle scalene anatomy can also significantly increase the risk of developing neurogenic TOS.
Venous or arterial TOS are almost always due to some type of underlying congenital deformity of the first rib, the presence of a cervical rib, or anomalous fibrous bands which result in an unusually tight space around the vein or artery leading to compression.
How do you diagnose Thoracic Outlet Syndrome?
Diagnosing venous or arterial thoracic outlet syndrome is much easier than neurogenic TOS as there are obvious physical exam findings such as swelling or lack of arterial pulses. Imaging studies such as ultrasound, CT scans or MRI along with venography or arteriography are all reliable methods for diagnosing these rare forms of TOS.
Neurogenic TOS is much more difficult to diagnose, even though it occurs much more frequently, for a number of reasons. First, many of the symptoms produced by neurogenic TOS mimic nerve compression at the level of the cervical spine. Most doctors are conditioned to think that widespread pain, numbness or weakness involving the entire upper extremity is always due to a problem with the cervical spine (neck). Neurogenic TOS also frequently produces significant pain in the shoulder area. The diagnosis of an orthopedic shoulder problem is another common “red herring” that distracts from the real problem of compression of the brachial plexus.
Second, because so many different nerves are impacted by compression of the brachial plexus, the patient often presents with several different complaints such as “shoulder pain,” “headache,” “jaw pain,” “upper back pain,” and other vague or non-specific symptoms of numbness, pain or sensory changes in the arm and/or hand. Patients presenting with such a constellation of seemingly disparate symptoms as in the example above often overwhelm the doctor trying to diagnose them. This typically results in the treating physician developing “tunnel vision” where they latch onto one symptom that makes sense to them and ignore or discount everything else. Focusing on “shoulder pain” or “neck pain” above everything else can lead to unnecessary spine or shoulder surgery which invariably does not solve the problem.
Third, the only really accurate way to diagnose neurogenic TOS is to be evaluated by someone who understands the peripheral nerve anatomy well, knows what the presenting symptoms and signs look like, and can perform a detailed upper extremity peripheral nerve evaluation, including a detailed history. As the technology of medicine has become better and better, physicians have started to rely less and less on their history and physical examination skills. EMG/NCV studies, and the usual imaging studies like CT scans and MRIs are very poor at identifying compression of the brachial plexus. More recent advances in using MRI to look at nerves (MR neurography) is still in its infancy and not readily available in most areas around the country.
What kind of treatment options are available for Thoracic Outlet Syndrome?
The treatment options for TOS depends on the particular type you have. Venous and arterial TOS are typically treated by a vascular surgeon. In the case of venous TOS, blood clots are usually dissolved first and then the underlying pathology that led to the compression (cervical rib, abnormal first rib, etc.) must be addressed surgically. In arterial TOS, the narrowed or damaged section of the artery must be repaired or replaced, as well as the underlying pathology addressed.
For neurogenic TOS, treatment depends on the severity of the symptoms and length of time that the symptoms have been present. For milder cases or patients who have not had the problem for very long, the symptoms will often resolve on their own with time. Physical therapy, medication, and lifestyle modification (where possible) can shorten the healing time significantly if the brachial plexus compression is recognized in the early stages. Unfortunately, due to the difficulties involved with correctly diagnosing neurogenic TOS, very few patients end up being diagnosed accurately early on. In severe cases of brachial plexus compression, or in instances where the problem has been present for a significant amount of time (often years), the most effective course of action is surgical decompression.
Surgery for brachial plexus compression typically involves the entire removal of the anterior scalene muscle, as well as partial or complete removal of the middle scalene muscle. While this may sound drastic, these small muscles are located deep in the neck and removing them leaves the patient with no visual (aesthetic) or functional deficit. It is also usually necessary to remove any external scar tissue (fibrosis) from around the nerves to restore the ability of the nerves to glide through the surrounding tissue with movement of the arm and shoulder which is very important. In severe cases, an internal neurolysis of part or all of the brachial plexus may be needed. This involves opening or stripping off the external layer of the nerves, called the external epineurium, which can become scarred and thickened, acting like the tight skin on a sausage and independently compress the internal nerve structures.
It is important to emphasize that most surgeons who perform brachial plexus decompression surgery include removal of the first rib. This is due to the historically incorrect assumption that the actual pressure point on the brachial plexus occurs between the clavicle (collar bone) above and the first rib underneath. Excision of the first rib is a very dangerous, morbid procedure which is not necessary in greater than 99% of patients with neurogenic thoracic outlet syndrome. Only in cases of a congenital or acquired deformity of the first rib does removal become important for a good outcome. The actual compression point in the vast majority of patients with neurogenic thoracic outlet syndrome is between the anterior and middle scalene muscles. Removal of these muscles and the scar tissue around the nerves is the key to a good outcome, not removal of the first rib. Avoiding resection of the first rib also significantly decreases the recovery time from surgery.
The Tollestrup Team Can Help
Dr. Tim Tollestrup and his team can help. Call us at 702-666-0463 or fill out the form on this page to set up a consultation to determine your options.