Persistent and Recurrent Thoracic Outlet Syndrome

What is persistent and recurrent thoracic outlet syndrome?

Persistent thoracic outlet syndrome (TOS) is a condition when the disease continues or even worsens after surgery. Recurrent thoracic outlet syndrome is slightly different from persistence. Recurrence means that symptoms of TOS return after a brief period of improvement. This short time frame is often called “honeymoon”. Symptoms can remain or return for several reasons, and finding which applies matters more than the label. Pain during the first weeks and months of recovery is expected and is not, by itself, a sign of recurrence.

Causes of Recurrent Thoracic Outlet Syndrome

Wrong diagnosis

There are many conditions that may mimic thoracic outlet syndrome. Cervical disc herniation, shoulder joint problems, fibromyalgia, and Raynaud’s disease may be misdiagnosed as TOS.

1. Cervical disc herniation. There are many common features between TOS and disc herniation. Both diseases are associated with nerve compression. Consequently, cardinal symptoms like pain, numbness, and weakness are present in both diseases. Therefore, differential diagnosis can be challenging. To make things worse, some patients may simultaneously have cervical disc herniation and TOS.
2. Fibromyalgia can be very easily mistaken for TOS and vice versa. The main symptom in fibromyalgia patients is pain. The painful area may be very similar to TOS, but numbness and weakness are uncommon in fibromyalgia.
3. Raynaud’s disease is a chronic condition affecting arteries and leading to progressive narrowing. As a result, patients develop cold intolerance and ischemia in their arms and hands. Fingertips are particularly affected. The main difference between TOS and Raynaud’s phenomenon is the absence of other thoracic outlet-related symptoms like nerve injury and venous obstruction. Also, from a diagnostic standpoint, angiography in Raynaud’s disease shows progressive narrowing of all arm, hand, and finger arteries, while in arterial TOS, only the subclavian artery is compressed from outside above the first rib.
4. Parsonage-Turner Syndrome is an extremely rare disorder affecting the brachial plexus. It has an acute onset, and the pain is excruciating. The pain is followed by severe weakness in the arm. Upon recovery, patients usually develop permanent paresis of the arm and hand muscles. The main differences between PTS and TOS are acute onset, severity, lack of pain after recovery, and absence of vascular involvement.
5. Complex regional pain syndromes. There are two types of CRPS. Type 1 is previously known as reflex sympathetic dystrophy and is more frequent. Type 2 used to be called causalgia. These are highly debilitating syndromes significantly affecting patients’ quality of life. CRPS develop after relatively minor injury like trauma, fracture or surgery. With time the intensity of pain surpasses the initial injury and spreads to other areas. Usually hands, arms, feet and legs are affected. The degree of pain is disproportionate to original injury and there are additional symptoms. Autonomic nervous system is frequently involved (old name used to be reflex sympathetic dystrophy). There might be episodes of swelling, redness, coldness, sweating. Chronic inflammation is typical and there is also evidence of immune system involvement. The difference between CRPS types is the presence of peripheral nerve injury in type 2.

The diagnosis of thoracic outlet syndrome is made clinically, and radiographic confirmation is not always reliable. Misdiagnoses are very frequent and can produce poor outcomes. A crucial step towards success is a thorough evaluation conducted by an experienced specialist.

Compression that remains after surgery

Surgery aims to decompress the nerves and vessels and is called thoracic outlet decompression (TOD). After an operation, symptoms can come from compression that is still present, from scar tissue around the nerves, from another condition, or from nerve damage that recovers slowly or incompletely. Remaining compression can involve a first rib that was left in place or only partly removed, as well as residual muscle or fibrous bands. Studies of patients referred for repeat surgery describe what was found in that selected group; they do not show how often each kind of first operation fails.¹

Scalenectomy and neurolysis without rib resection

Historically, the first rib resection was the initial treatment for thoracic outlet syndrome. However, complications and technical difficulties associated with first and additional rib removal led to the proposal of an alternative first rib-sparing approach in the 1920s.² The technique is mostly unchanged, and it is still used today. The anterior and middle scalene muscles are partially removed, and the neuro-vascular bundle is relieved from compressive soft tissue bands. The approach became popular for its simplicity and lower risk.

In the 1940s to 1960s, many surgeons reported disappointing results and returned to rib removal.^{3, 4}

A small randomized trial in 2005 found better results with transaxillary first-rib resection than with the particular rib-sparing nerve release it tested.⁵ More recent series report good results from selected rib-sparing operations, so the approach remains in use.⁶ When symptoms persist after a rib-sparing operation, a first rib left in place is one of the possibilities to assess, alongside the others above.

Incomplete first rib removal

When the first rib contributes to compression, removing it is a central part of the operation, and how much of the rib is removed varies between surgeons and approaches.

Typically, TOD surgery is performed either from the front of the neck (supraclavicular approach) or from the armpit (transaxillary approach). Yet, it is technically difficult and risky to totally remove the first and accessory ribs via these approaches. The reason is the anatomical relation of the first rib. The first rib has joint connections with the spine posteriorly and with the sternum anteriorly. The posterior and anterior regions of the first rib are very deep and hard to access.

Anatomically the brachial plexus, subclavian vein and subclavian artery pass over the first rib. These are the delicate structures which should be protected at all cost. Yet in order to access the first rib these nerves and vessels should be moved to expose the bone. Like the first rib, the accessory cervical rib posteriorly has either a joint or bony connection with the spine. The proximity to the brachial plexus is even more for the accessory rib than for the first rib, making safe exposure and total removal difficult. Therefore, surgeons prefer not to risk these frail, vital structures and deep section parts remain untouched.

The middle section of the first rib and the tip of a cervical rib are easier and safer to reach, so with these approaches the front or back ends of the rib may be left in place.

A remaining rib can contribute to ongoing compression in some patients: in one study, patients with a remaining or remnant first rib and recurrent symptoms improved after further surgery that included removing it.⁷ Its presence or size alone does not establish the cause of symptoms, though; in a long-term follow-up, the length of the remaining rib was not related to how patients were doing a decade later.⁸

Some patients get worse after surgery. Dr Robert Leffert described one possible reason, which he called the “missing third”.⁹

In this proposed mechanism, when only the middle section of the first rib is removed, the brachial plexus can adhere to the back rib stump and the subclavian vein to the front one. Normally, nerves and vessels do not adhere to the bone. However, after surgery, scar tissue develops in the surgical field and sticks everything indiscriminately. This scar tissue anchors nerves and vessels to the bone. The subclavian artery is usually spared because there is no bone left underneath, and it usually sinks down with surrounding soft tissue. This soft tissue “sinking” pulls the nearby brachial plexus and subclavian vein down. With rib stumps underneath and scar limiting movement, the brachial plexus and subclavian vein may be strained. This is one possible explanation, not something that happens after every partial rib removal.

When symptoms persist or return after TOS surgery, reassessment should establish what the first operation included and whether the present symptoms come from remaining compression, scar tissue, another diagnosis or incomplete nerve recovery; bring the operative report and earlier scans. Further treatment may involve rehabilitation, symptom management or, in selected patients with a clear surgical target, revision decompression. Revision is more complex because of scarring and altered anatomy, so it belongs with surgeons experienced in it, and its likely benefit and risks need a specific discussion. Even after an anatomically complete operation, some patients develop recurrent symptoms; selected patients with scar around the nerves have improved after a further nerve release.¹⁰ Our guide to first-rib removal and the full decompression plan explains what an operation can and cannot address.

Next: PURED Procedure for Thoracic Outlet Syndrome

References

1. Jammeh ML, Ohman JW, Vemuri C, et al. Anatomically Complete Supraclavicular Reoperation for Recurrent Neurogenic Thoracic Outlet Syndrome: Clinical Characteristics, Operative Findings, and Long-term Outcomes. Hand (N Y). 2022;17(6): 1055-1064. https://doi.org/10.1177/1558944720988079[↩]
2. Adson AW, Coffey JR. Cervical Rib: A Method of Anterior Approach for Relief of Symptoms by Division of the Scalenus Anticus. Ann Surg. 1927;85(6): 839-857. https://doi.org/10.1097/00000658-192785060-00005[↩]
3. Clagett OT. Research and prosearch. J Thorac Cardiovasc Surg. 1962;44: 153-66. https://pubmed.ncbi.nlm.nih.gov/13879636/[↩]
4. Raaf J. Surgery for cervical rib and scalenus anticus syndrome. J Am Med Assoc. 1955;157(3): 219-223. https://doi.org/10.1001/jama.1955.02950200017005[↩]
5. Sheth RN, Campbell JN. Surgical treatment of thoracic outlet syndrome: a randomized trial comparing two operations. J Neurosurg Spine. 2005;3(5): 355-363. https://doi.org/10.3171/spi.2005.3.5.0355[↩]
6. Johansen K. Rib-sparing scalenectomy for neurogenic thoracic outlet syndrome: Early results. J Vasc Surg. 2021;73(6): 2059-2063. https://doi.org/10.1016/j.jvs.2020.12.052[↩]
7. Likes K, Dapash T, Rochlin DH, Freischlag JA. Remaining or residual first ribs are the cause of recurrent thoracic outlet syndrome. Ann Vasc Surg. 2014;28(4): 939-945. https://doi.org/10.1016/j.avsg.2013.12.010[↩]
8. Nuutinen H, Kärkkäinen JM, Mäkinen K, et al. Long-term outcome over a decade after first rib resection for neurogenic thoracic outlet syndrome. Interact Cardiovasc Thorac Surg. 2021;33(5): 734-740. https://doi.org/10.1093/icvts/ivab172[↩]
9. Leffert RD. Complications of surgery for thoracic outlet syndrome. Hand Clin. 2004;20(1): 91-98. https://doi.org/10.1016/s0749-0712(03)00084-2[↩]
10. Jammeh ML, Yang A, Abuirqeba AA, et al. Reoperative Brachial Plexus Neurolysis After Previous Anatomically Complete Supraclavicular Decompression for Neurogenic Thoracic Outlet Syndrome: A 10-Year Single-Center Case Series. Oper Neurosurg (Hagerstown). 2022;23(2): 125-132. https://doi.org/10.1227/ons.0000000000000252[↩]