The rare origin of the suprascapular artery arising off the internal thoracic artery in the presence of the thyrocervical trunk: clinical and surgical implications

During routine dissection of the subclavian artery and its branches, the suprascapular artery was found arising from the proximal end of the internal thoracic artery in only the left side of a 68-year-old Caucasian male, despite the presence of the thyrocervical trunk on the ipsilateral side. The suprascapular artery ran deep to the proximal one-third of the clavicle then continued its usual course, running parallel to the suprascapular nerve and passing over the superior transverse scapular ligament distally. Knowledge of this variant origin of the suprascapular artery is clinically important because the internal thoracic artery is utilized for a majority of the 800,000 coronary artery bypass surgeries performed worldwide each year. Its course deep to the clavicle is also significant due to clavicular fractures accounting for approximately 5-15% of adult bone fractures.