We present herein the cases of two patients with thoracic outlet syndrome (TOS) who required arterial reconstruction due to gangrene of the fingers and/or hand. In both patients, the cervical ribs had produced intimal injury of the subclavian arteries, and the successive distal arterial embolism brought about severe ischemia of the affected upper extremity. To treat the TOS, the cervical ribs were resected through a supraclavicular incision. In the first patient, arterial reconstruction was performed from the subclavian artery to the radial collateral artery, a branch of the deep brachial artery, which resulted in minimizing amputation of the gangrenous hand. In the second patient, resection and direct anastomosis of the injured subclavian artery were performed, and bypass surgery from a brachial artery to an interosseous artery was carried out, preserving finger function. Reversed saphenous vein grafts were utilized and Esmarch's bandage technique was applied as a substitute for a vascular clamp in both patients. Following these case reports, we discuss the technique of performing distal bypass in the upper extremities and comment on the usefulness of Esmarch's bandage technique for preserving upper extremity function.