Occlusion of the posterior humeral circumflex artery: detection with MR angiography in healthy volunteers and in a patient with quadrilateral space syndrome.

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of MR angiography in detecting occlusion of the posterior humeral circumflex artery and to determine if the finding is specific for the diagnosis of quadrilateral space syndrome. SUBJECTS AND METHODS: Two-dimensional fast low-angle shot MR angiography was used to image both shoulders of one symptomatic patient and six asymptomatic volunteers (10 posterior humeral circumflex arteries).
RESULTS: With the arm in a neutral position, the posterior humeral circumflex arteries appeared normal on MR angiograms of all subjects. However, when the arm was in abduction, occlusion of the posterior humeral circumflex artery was seen both in the symptomatic patient and in 80% of the asymptomatic volunteers.
CONCLUSION: Our data show that occlusion of the posterior humeral circumflex artery is common in asymptomatic volunteers. Thus, MR angiography has no value in the diagnosis of quadrilateral space syndrome.