Thoracic Outlet Syndrome: Therapy [Clinical Review Discussion]

As discussed in the thoracic outlet syndrome (TOS) prevention and diagnosis monographs, TOS is a very controversial topic in the medical literature.  Disagreements over methods to arrive at a diagnosis, whether it is under-diagnosed or over-diagnosed or even exists at all have resulted in a gross lack of evidence related to treatment.  A recent Cochrane Review (1) could only locate 1 randomized clinical trial (RCT) on treatment.  That study was small, highly suspect of bias and compared 2 surgical protocols (2).  For the practitioner who desires to practice in a non-evidence based environment, TOS is the perfect diagnosis.  Outside of a handful of case series and case reports, virtually all the evidence on treatment is based on expert opinion or is anecdotal.

Most studies combine a variety of approaches in treatment.  Most include strengthening, stretching, postural training, manipulation/mobilization and breathing exercises.  The reader should note although the different treatment protocols have been broken down into separate groups, almost all protocols include a mixture of interventions.  Success rates vary with the study but generally 62% to 88% of patients experience improvements or are satisfied with treatment (3;4).  Several authors have stated early intervention is important to success in the treatment of TOS as delayed treatment may lead to intraneural scarring and chronicity (5;6).

Most studies recommend 10 to 12 treatment sessions over a month’s time with most protocols recommending long term home exercise programs (7).  Improvement should become apparent within the first 6 to 8 treatments or it is unlikely improvement will occur according to Ingesson et al. (8).   

A very interesting study was published in 2001 in the Journal of Vascular Surgery by Landry et al.  They found there were no statistical differences in outcomes between 79 disputed TOS patients who were treated with either conservative care or surgical care at an average follow-up of 4.2 years.  The authors of this study concluded that “it is essential that proponents of surgical treatment of disputed TOS prove that surgical therapy is superior to conservative management” and until then “we will continue to favor conservative therapy” (9).

Up to 95% of TOS cases fall into the neurological TOS category (true and disputed) (10).  Although it is uncommon, venous TOS can result in a potentially life threatening upper extremity venous thrombosis.  The physician must have the knowledge and skill to recognize the different forms of TOS in order to minimize risk to his/her patient.  Most cases of TOS can be initially treated with conservative means.  Patients that do not respond or worsen may, due to the severity of symptoms, have no other option other than surgical intervention.