New Paradigms for Thoracic Outlet Compression and Thoracic Outlet Syndrome, with or without Complications or Sequelae: A Trans-Continental and Trans-Disciplinary Opinion Paper

Abstract

The anatomy of the human shoulder predisposes the neurovascular bundle to compression at different levels of the thoracic outlet during abduction of the arm. There are four possible levels of compression at the thoracic outlet pathway: at the costo-clavicular angle, the inter-scalenic angle, under the pectoralis minor muscle or at the level of the humeral head. The positional thoracic outlet compression (TOC) often remains completely asymptomatic. When symptomatic, compressions are collectively referred to as thoracic outlet syndrome (TOS) and may require surgery if physical therapy fails to improve symptoms. The “thoracic outlet compression with complications or sequelae” (the acronym of which is “TOC-CS”, which can be simplified as “TOX”) will almost invariably lead to surgery to release the compression, and other possible treatment targeting the complications as required. There is a continuum between TOC, TOS and TOX, which are simply different clinical stages of the same mechanical issue, just like the Rutherford grades represent different stages of lower extremity arterial disease. We believe that discriminating between TOC, TOS and TOX clarifies clinical definitions and their respective treatment options. TOC is to be considered as a physiological positional phenomenon, TOS requires medical or surgical treatment and surgery should be considered as a primary option in TOX.

Role of Lifestyle in Thoracic Outlet Syndrome: A Narrative Review

“…To date, asymptomatic cases of neurovascular positional compression have led many authors to suggest that tests used to diagnose TOS either perform poorly or have little discriminative value [11,[14][15][16][17]. We recently proposed that these cases of positional compression without symptoms or complications should not be named TOS but "thoracic outlet compressions" (TOCs) in order to avoid confusion between the two conditions [18]. Ultimately, a small number of patients with TOC or TOS will develop complications or sequelae (CS) as a result of the chronic conflict between the neurovascular bundle and the adjacent structures, such as vascular thrombus or aneurysms [19][20][21], Gilliatt and Sumner hand, and peri-neural fibrosis [22][23][24][25][26].…”

“…Ultimately, a small number of patients with TOC or TOS will develop complications or sequelae (CS) as a result of the chronic conflict between the neurovascular bundle and the adjacent structures, such as vascular thrombus or aneurysms [19][20][21], Gilliatt and Sumner hand, and peri-neural fibrosis [22][23][24][25][26]. We also proposed that such cases of "thoracic outlet compression with complications or sequelae" should not be called TOS because the complication may be asymptomatic; instead, they should be referred to as "TOX" (which is a simplified version of TOC-CS) [18]. This TOC-TOS-TOX paradigm will be used throughout the present manuscript [18].…”

“…We also proposed that such cases of "thoracic outlet compression with complications or sequelae" should not be called TOS because the complication may be asymptomatic; instead, they should be referred to as "TOX" (which is a simplified version of TOC-CS) [18]. This TOC-TOS-TOX paradigm will be used throughout the present manuscript [18].…”

Editorial: Thoracic outlet compression, thoracic outlet syndrome, with or without complications or sequelae: mechanisms, investigations and treatments

“…Defining TOS is not the least of the problems. We recently proposed that contrary to most publications, asymptomatic compression should not be referred to as thoracic outlet syndrome (TOS) but rather as thoracic outlet compressions (TOC), while “thoracic outlet compression with complications or sequelae” would be called TOX ( Abraham et al, 2023 ). In this perspective, the original case reported by Mansouri and Lutz is fascinating: how should this case be called?…”