Migration of Kirschner pin from clavicle into ascending aorta.

Kirschner pins are widely used for fixation of bone, with few and very rarely serious complications. A case is described in which a Kirschner pin migrated in 10 days from the sternal end of the left clavicle into the lumen of the ascending aorta. The exact location of the pin remained unknown until right thoracotomy, during which X-ray examination revealed the unexpected situation. The pin was simply extracted by pushing it through the vessel wall. The patient recovered uneventfully. The complication could have been prevented by bending the outer part of the pins. The possible route of migration is discussed.