top of page

Thoracic Outlet Syndrome: Not The End of The Road

My patients have a tendency to come in pairs-- I've said this for a long time. Recently there have been "pairs" of patients referred to me for treatment of Thoracic Outlet Syndrome (TOS), a rare condition that is characterized by compression of nerves or arteries leading into an upper extremity. As with many diagnoses (among my favorites: biceps tendinitis, hip bursitis, shoulder impingement, and low back pain), the label of "Thoracic Outlet Syndrome" identifies the symptoms, but doesn't immediately point to the reason behind them. In order to treat the condition, you have to know where it came from. And thus, the patient's referral to Physical Therapy.

Paths leading to Thoracic Outlet Syndrome (TOS)

In general, the only consensus we have in the medical community regarding TOS is the presence of "neural and/or vascular compression", which leaves a lot of room for interpretation (and thus is where the agreement stops). The incidence, pathoanatomical contributions, diagnosis and treatment are still widely debated. It is estimated that 90% of cases are neurological (nerve compression only), whereas 3-5% are venous and less than 1% are arterial. While the presence of a blood clot or more serious medical complication (i.e. a crush injury) certainly points to the need for surgical intervention, I believe many surgical cases can be avoided with the appropriate conservative intervention.

Most cases of Thoracic Outlet Syndrome can be successfully managed with the appropriate conservative treatment.

A common finding in my recent referrals is that the diagnosis of TOS was the last "domino to fall"; in other words, these conditions developed after a long history of gradual deconditioning, overuse, and abnormal movement patterns in the shoulder and thorax. For instance, after unrelenting fatigue from throwing, poor conditioning when returning to play, or progressively worsening posture. In most cases, TOS can be successfully managed with conservative care (exercise and/or rehab). A physician's therapy script for TOS typically includes suggested treatments such as pectoralis major/minor stretching, postural stabilization and activity modification. My argument here is that we need to understand how/why this condition developed in the first place because I've seen patients that undergo a TOS surgery with removal of the 1st rib that still have TOS symptoms. We can't reverse the domino effect if we don't know where the dominos started. Therefore, there are some important questions to ask when taking a patient's history:

"A good history is more important than the exam" -- James Andrews, MD, American Sports Medicine Institute

Treatment of TOS obviously needs to address lots of common clinical findings, including soft tissue mobility, available joint range of motion (at the spine, thorax and shoulder), and correcting abnormal breathing patterns. But one of the most common findings in my

history and exam is significant scapular dyskinesia or weakness on the side with TOS, particularly related to the serratus anterior. The serratus anterior is one of my favorite (and most commonly neglected) muscles. It has such an important job in many different ways- throwing, pushing up from the floor, reaching for that dish in an overhead cabinet, and decompressing the brachial plexus. Anatomically, the serratus anterior provides a downward force to the 1st rib, thus opening the space under the clavicle to allow the neural and vascular structures to exit the subclavicular space without being pinched. So while I am certainly addressing any possible pectoralis major/minor tension to decompress the anterior chest wall, in order to make my manual interventions 'stick', I have to emphasize training the muscle memory & capacity of the serratus anterior and other scapular stabilizers.

One misconception I see in treating high level patients (i.e. athletes or highly active individuals) is the assumption that they have enough baseline strength and recruitment in the serratus anterior and scapular muscles to 'skip' the most basic (aka easiest) recruitment exercises. By the time these patients make it to my clinic, they are "Master Compensators", and can blow through exercises like serratus punches and planks without feeling significantly challenged. This is because the pectoralis major/minor, latissimus dorsi and subscapularis serve as assistants to the serratus anterior in arm positions at or below 90 degrees. When these athletes are given exercises that should recruit the serratus, they compensate instead with these other stronger muscles. In this instance, we need to ensure proper form or take 1 step back in order to take 2 steps forward.

If you feel like you're treading water with a patient's progress, you probably need to reduce the intensity of the activity and start with the most basic, isolating movements.

One of my favorite research articles (that ALL my PT students are assigned) is an article

published in 2009 by Reinold et al examining the electromyographic (EMG) activity of the rotator cuff and scapular muscles during various exercises and movements. According to this research, the pectoralis major/minor and serratus anterior both protract the scapula. This is the #1 reason why I don't start strengthening the serratus anterior with supine scapular punches. BUT, the pectoralis major/minor does NOT assist with elevation of the arm or upward rotation of the scapula (particularly above 90 degrees). Ideally, we are looking for exercises that have a high serratus anterior to low pectoralis major EMG ratio.

The needs of each TOS case can be drastically different. Emphasizing mobility of the spine, thorax and shoulder through soft tissue restrictions and/or mobilization should always come first. Even the best recruitment exercises can't fight significant mobility restrictions. But in order to make this newfound mobility last after the patient leaves the clinic, we should utilize corrective or strengthening exercises. These conditions don't happen overnight, so the corrective/recruitment exercises used need to start with the very basics.

Gain the motion, then train the motion.

Once the basics are mastered, then we can move on to more complex/challenging exercise and then eventually addressing the very FIRST domino: correction of multi-segmental movement dysfunction (i.e. throwing, squat, or work mechanics) or teaching how to reduce strenuous repetition through rest and positioning. The diagnosis of TOS doesn't have to be the end of the road, nor does it have to become a chronic condition-- we just need to make sure we're actually starting at the beginning and addressing the reason why this condition developed in the first place.

673 views0 comments


bottom of page