Thoracic outlet syndrome (TOS) represents a group of heterogeneous and potentially
disabling upper-extremity disorders that are caused by extrinsic compression
of neurovascular structures between the first rib and clavicle. There
are 3 distinct types of TOS, which are classified according to the principal anatomic
structures involved and the clinical syndromes that result: neurogenic TOS, venous
TOS, and arterial TOS. All 3 forms of TOS are rare, but they are clinically important
because, when unrecognized or inadequately treated, they can cause chronic pain
syndromes, long-term restrictions in use of the upper extremities, limb-threatening
complications, and substantial disability even in relatively young, active, and otherwise
healthy individuals. Accurate diagnosis of TOS can be a substantial challenge
in practice, because of a lack of physician awareness, clinical features that overlap or
mimic more common conditions, and an absence of clearly defined (objective) diagnostic
criteria. There is also persistent controversy regarding the efficacy of the various
treatment approaches for TOS—approaches that vary in accordance with the experience,
expertise, and specialty of the physician. The purpose of this presentation is to
briefly review current protocols for the diagnosis and treatment of TOS and to highlight
the clinical-management challenges that remain.