INVESTIGATION OF NONSPECIFIC NEUROGENIC THORACIC OUTLET SYNDROME

Objective. To determine the value of investigations for nonspecific ne urogenic thoracic outlet syndrome (NNTOS) and formulate a rational dia gnostic approach. Design. Retrospective review. Setting. Thoracic surg ery clinic. Patients. Fifty-six patients referred with a presumptive d iagnosis of NNTOS. Patients with arterial, venous, or true (classic) n eurogenic TOS were excluded. interventions, All patients underwent car eful history and examination. Fifty-three had cervical spine radiograp hs, 45 had electrophysiologic testing, and 30 patients had arterial do ppler studies. Main outcome measures. The value of investigations that documented a diagnosis other than NNTOS could be assessed but objecti ve evaluation of investigations that appeared to support a diagnosis o f NNTOS was not possible. No standard diagnostic criteria exist for NN TOS. Results. Forty (71%) patients were female. Thirty-four (61%) pati ents had a pulse deficit with provocative maneuvers. Cervical spine ra diographs showed cervical ribs in 10 patients and degenerative disease in 11 patients. Electrophysiologic testing demonstrated carpal tunnel syndrome in II patients. Arterial Doppler studies were strongly posit ive for TOS in 10 patients. Thirty-six (64%) patients were diagnosed w ith conditions other than NNTOS. The diagnosis of NNTOS was accepted i n 20 (36%) patients. All 20 patients were initially treated conservati vely but 3 (5%) eventually underwent surgery. Conclusions. NNTOS is a diagnosis of exclusion. Two thirds of patients referred to a thoracic surgery clinic were eventually diagnosed with conditions other than NN TOS. Objective evaluation of investigations that may support a diagnos is of NNTOS is not currently possible.