TOS surgery is a procedure to relieve compression of nerves or blood vessels in the thoracic outlet, the narrow space between your collarbone and first rib. The most common operation involves removing the first rib to widen that space, though surgeons may also release tight muscles in the area. The specific approach depends on whether the compression affects nerves (neurogenic TOS, the most common type), veins (venous TOS), or arteries (arterial TOS).
Why Surgery Is Recommended
TOS surgery is typically reserved for people who haven’t improved with physical therapy, postural corrections, and other non-surgical treatments. Diagnosing TOS in the first place can be challenging because it’s largely a diagnosis of exclusion, meaning doctors rule out other conditions first through physical exams, imaging, vascular studies, and provocative tests that reproduce your symptoms by having you move or lift your arms.
For neurogenic TOS, the most widely referenced diagnostic framework requires three of four criteria: symptoms consistent with thoracic outlet compression (pain or tenderness), signs of nerve compression that often worsen with arms overhead or hanging at your sides, no other condition that better explains the symptoms, and a positive response to a diagnostic injection into the scalene muscles of the neck. There’s no universally agreed-upon timeline for how long you need to try conservative treatment before surgery becomes an option, but most surgeons want to see a genuine course of physical therapy attempted first.
Venous TOS sometimes follows a more urgent path. When the subclavian vein is compressed at the junction between the collarbone and first rib, it can cause an acute blood clot in the arm, a condition called Paget-Schroetter syndrome. In these cases, clot-dissolving treatment is typically followed by first rib resection. A large meta-analysis found that this combination of clot dissolution followed by rib removal produced the best outcomes compared with either treatment alone.
Types of TOS Surgery
Almost all TOS operations center on one core goal: making the thoracic outlet wider so structures passing through it are no longer pinched. The two main procedures are first rib resection (removing part or all of the first rib) and scalenectomy (cutting the scalene muscles that attach to the rib and can tighten around nerves or vessels). These are sometimes performed together.
The data on which combination works best is mixed. One review found that scalenectomy combined with rib resection yielded 99% patient satisfaction compared with 57% for scalenectomy alone. However, another review reported the opposite pattern: isolated scalenectomy through a supraclavicular (above the collarbone) approach showed 85% success rates with a 13% complication rate, while adding rib resection dropped success to the mid-70s and pushed complications above 20%. This is why surgical planning is highly individualized.
Transaxillary Approach
In the transaxillary approach, the surgeon reaches the thoracic outlet through a small incision in your armpit. This provides a direct line of sight to the first rib. The surgeon divides the muscles attached to the rib, isolates the rib from the surrounding nerves and veins, and removes it. Once the rib is out, the entire outlet is freed from external compression. The incision is relatively hidden, and this approach is one of the most commonly used for first rib resection.
Supraclavicular Approach
This approach goes in through an incision just above the collarbone, giving the surgeon direct access to the scalene muscles and the brachial plexus (the nerve bundle running through the outlet). It’s particularly useful when the primary goal is scalenectomy or when the surgeon needs to address a cervical rib, an extra rib that some people are born with. Because the nerves are directly visible, some surgeons prefer this route for neurogenic TOS.
Risks and Complications
TOS surgery carries real but relatively uncommon risks. A 17-year review of surgical outcomes at one center found that the most frequent complication was pneumothorax (a small lung collapse caused by air leaking into the chest cavity during rib removal), occurring in about 6% of cases. This usually resolves on its own or with a temporary chest tube. Phrenic nerve complications, which can temporarily affect the diaphragm and breathing, occurred in about 5% of cases. Other potential complications include injury to surrounding nerves or blood vessels, wound infection, and incomplete symptom relief.
What Recovery Looks Like
Recovery from TOS surgery follows a gradual timeline over about six weeks, with activity building slowly. For the first two weeks, you’ll wear an arm sling when walking or riding in a car, but you’re encouraged to keep the arm out of the sling and elevated on pillows when sitting or resting. Gentle range-of-motion exercises, pendulum shoulder movements, and hand exercises start on the first day after surgery, done three to four times daily. Each movement is held for about five seconds, stopping just before the point of pain.
At the two-week mark, sutures come out and you continue nerve and joint gliding exercises. By week three, scar massage begins and light weights may be introduced. Week four brings brachial plexus massage and the start of real strengthening work, though the pace here depends heavily on how active you were before surgery. Strengthening progresses through week five, and by week six you may begin ergonomic training and work-simulated activities. Throughout this entire period, you should not lift more than five pounds.
Physical therapy is a central part of recovery, not an optional add-on. The progression is highly individualized, with therapists adjusting weekly based on your pain levels and function.
How Success Is Measured
Defining “success” after TOS surgery has been a challenge in the medical literature because symptoms like pain, numbness, and weakness are subjective. A Johns Hopkins team developed a practical benchmark by surveying patients and asking them to rate their percentage of symptom improvement compared with before surgery. The median response was 80% improvement, so the team used that as the dividing line: 80% or greater improvement was considered a good outcome, and anything below was suboptimal.
This means most patients experience significant relief but not complete elimination of symptoms. Setting realistic expectations matters. TOS surgery tends to work best for people with a clear anatomical cause of compression and a well-documented failure of conservative treatment. People with venous or arterial TOS, where the compression is easier to confirm with imaging, often have more predictable surgical outcomes than those with neurogenic TOS, where the diagnosis itself can be less certain.