Local injections of corticosteroids can, in very rare cases, be complicated by Tachon syndrome-intense lumbar and/or dorsal and/or thoracic pain a few minutes after the injection, with rapid regression of the pain. Passing the drug into a vein through a nick made during the procedure could explain the pathophysiology of this disorder. We report two good cases illustrating the typical symptoms of this distressful syndrome. Diagnosis of Tachon syndrome is made by elimination of the usual medical and surgical causes, and physicians performing local injections should be aware of this phenomenon. The patient needs to be reassured of the temporal nature of the syndrome.