Thirteen patients with thoracic disc herniation have been operated on between 1960 and 1984. Nine presented with a progressive cord compression syndrome affecting sensory function more than motor. Four patients presented with acute cord compression. During this period, the authors have abandoned medullary angiography and myelography. The diagnosis is now based on computerised myelotomography. Three cases were treated by laminectomy with two postoperative deteriorations. Two cases were treated by a transthoracic approach which seemed to be too risky. Eight cases were treated through a postero-lateral approach, six being through a transverse arthropediculectomy using a microscope for better dissection of the vessels and Harrington rods to avoid secondary kyphosis. Seven of 9 cord syndromes were improved. Four cases with predominantly radicular syndromes were all improved.