Objectives To describe the spectrum of axillary artery pathology seen in high-performance overhead athletes and the outcomes of current treatment. Methods A retrospective review of patients that had undergone management of axillary artery lesions in a specialized center for thoracic outlet syndrome (TOS). Treatment outcomes were assessed with respect to arterial pathology and operative management. Results Nine male athletes were referred for arterial insufficiency in the dominant arm between January 2000 and August 2010, representing 1.6% of 572 patients treated for TOS (19% of 47 patients treated for arterial TOS). Seven were elite baseball pitchers (six professional, one collegiate), and two were professional baseball coaches with practice pitching responsibilities, with a mean age of 30.9 ± 2.9 years. Presenting symptoms included arm fatigue (five), finger numbness (four), cold hypersensitivity/Raynaud's (two), rest pain (one), and cutaneous fingertip embolism (one). Three patients underwent transcatheter thrombolysis prior to referral, including one with angioplasty and stenting. At angiography and surgical exploration 2.5 ± 0.8 weeks after symptom presentation (range, 1-8 weeks), six patients had occlusion of the distal axillary artery opposite the humeral head either at rest (three) or with arm elevation (three), one had axillary artery dissection with positional occlusion, and two had thrombosis of circumflex humeral artery aneurysms. Five patients had embolic arterial occlusions distal to the elbow. Treatment included segmental axillary artery repair with saphenous vein (n = 7; five interposition bypass grafts and two patch angioplasties), ligation/excision of circumflex humeral artery aneurysms (n = 2), and distal artery thrombectomy/thrombolysis (n = 2). Mean postoperative hospital stay was 3.8 ± 0.5 days, and the time until resumption of unrestricted overhead throwing was 10.8 ± 2.7 weeks. At a median follow-up of 15 months (range, 3-123 months), primary-assisted patency was 89%, and secondary patency was 100%. All nine patients had continued careers in professional baseball, although one retired during long-term follow-up. Conclusions Repetitive positional compression of the axillary artery can cause a spectrum of pathology in the overhead athlete, including focal intimal hyperplasia, aneurysm formation, segmental dissection, and branch vessel aneurysms. Prompt recognition of these rare lesions is crucial given their propensity toward thrombosis and distal embolism, with positional arteriography necessary for diagnosis. Full functional recovery can usually be anticipated within several months of surgical treatment, consisting of mobilization and segmental reconstruction of the diseased axillary artery or ligation/excision of branch aneurysms, as well as concomitant management of distal thromboembolism.