A case of arterial thoracic outlet syndrome.

66 year-old patient who goes to the Emergency Department because of a sudden pain of recent onset, 3 hours ago, in upper left limb, associates coldness and progressive loss of strength and limb sensibility, without trauma history. The patient is conscious and oriented to space and time, afebrile, hemodynamically stable. Rhythmic cardiac auscultation, without friction rubs or murmurs. Normal pulmonary auscultation. Bilateral carotid pulse, no murmurs. Pulse on ULL present at all levels. Pulse on URL absent at all levels.

The findings suggest acute arterial ischaemia. Vascular surgeons decide to ask for some imaging studies to evaluate the patient. Simple chest x-rays is performed, where symmetrical absence of fusion of the ossification nuclei of both clavicles is proved. It causes an alteration of the rib cage that adopts a bell morphology with a marked verticalization of the ribs. It is completed with angioCT to demostraste that the signs and symptoms are secondary to a thoracic outlet syndrome, in wich it is observed an abrupt change in the caliber of the right subclavian artery in a segment 5’5 cm long, that is located between the anterior and middle scalene muscles and this decrease in caliber is greater than 50%, with a very irregular light. It also associates soft tissue mass probably due to fibrotic/inflammatory changes. Ecography and MRI is recommended in order to confirm radiological alterations.

Thoracic outlet syndrome is usually characterised by neurological symptoms, more rarely venous, and exceptionally arterial. Within the causes of acute arterial ischaemia, one of the less frequent is congenital pseudoarthrosis of clavicle, and therefore often bilateral. For its diagnosis it is necessary to perform imaging tests. However, the main suspected diagnosis is based on the plan X ray that is provided.

- Charon J-P.M, Milne W, Sheppard DG, Houston JG.Evaluation of thoracic outlet syndrome.Clinical Radiology, 59 (2004), pp. 588-95 - Remy-Jardin M, Doyen J, Remy J, Masson P, Bonnel F, Debatselier P, et al.Helical CT angiography of thoracic outlet syndrom