Lincoln sign


Lincoln sign refers to forceful popliteal artery pulsation secondary to aortic regurgitation; exaggerated when the patient sits with legs crossed; and deemed positive if the elevated foot bobs up and down with each systolic contraction.

Lincoln sign is based on a hypothetical diagnosis for Abraham Lincoln, the 16th president of the United States. First observed by Lincoln himself, and expounded upon by the journalist Noah Brooks in 1863.

Lincoln sign aortic regurgitation 1863 big foot photograph
“Big foot” photograph by Alexander Gardner, 1863


1863 On Sunday, November 8, 1863 the famous “big foot” photograph was taken by Alexander Gardner in Washington. Lincoln noted that the outline of his left boot was blurred. The journalist Noah Brooks suggested that it was the throbbing of the arteries behind Lincoln’s knee that caused the leg to move almost imperceptibly.

One day we were looking at a photograph of the President, taken in a sitting position, with the legs crossed. Lincoln’s attention was attracted to the foot of the leg which was crossed above the other, and [Lincoln] said,

“Now, I can understand why that foot should be so enormous. It’s a big foot, anyway, and it is near the focus of the instrument. But why is the outline of it so indistinct and blurred ? I am confident I did not move it.”

I studied it for a moment, and told him that probably the throbbing of the large arteries in side of the bend of the knee caused an almost imperceptible motion. The President, very much interested in the discovery,’ as he called it, immediately took the position of the figure in the picture, and, narrowly watching his foot, exclaimed,

” That’s it ! that’s it! Now, that’s very curious, isn’t it.”

Noah Brooks 1878

1933 Cardiologist Sir Thomas Lewis described the quality of the pulse-wave of aortic incompetence:

All the pulses of the body jerk forcibly. The abdominal aorta throbs violently. As it travels, the pulse-wave rises more and more steeply and to a higher crest, and so it frequently happens that the abrupt jerking (or water-hammer) quality is extreme in the dorsum of the foot

Lewis 1933

1950 Cardiologist Aldo Augusto Luisada described the “arterial dance” associated with aortic insufficiency

…the abrupt rhythmic extension of one leg when crossed over the other coincident with systole.

Luisada 1950

1961 Abraham M. Gordon suggested Lincoln suffered from Marfan syndrome.

Abraham Lincoln was tall, loose-jointed, kyphotic, dolichocephalic, with unnaturally long, thin, arms and legs. The Marfan Syndrome, presumably inherited from his mother, is believed to explain Lincoln’s morphological appearance.

Gordon 1961

1964 Harold Schwartz provided further genealogical evidence of Marfanoid characteristics

The Marfan syndrome was found in a male descendant of Mordecai Lincoln II, great-great-grandfather of Abraham Lincoln. The common ancestry of the patient and the 16th president appears to establish genealogically that Lincoln’s unusual morphological characteristics were manifestations of the genetically determined arrangement of connective tissue described by Marfan in 1896.

Schwartz 1964

1972 Schwartz presented his theory that President Lincoln, two years before his assassination, had physical findings consistent with aortic insufficiency, as a complication of the Marfan syndrome.

Considering, then, the presence of the Marfan syndrome as previously established in Mr. Lincoln; the frequency of aortic valvular incompetency in that condition; the hemodynamics of aortic regurgitation; the graphic data of the Gardner photograph as detected by the President himself; the hypothesis of Brooks and its clinical confirmation by Lincoln…the evidence in the case of the President becomes highly consistent with aortic insufficiency and regurgitation.

Schwartz 1972

Associated Persons

Alternative names

  • Lincoln-Brooks sign of aortic insufficiency
  • Schwartz sign


eponymictionary CTA


the names behind the name

BA MA (Oxon) MBChB (Edin) FACEM FFSEM. Emergency physician, Sir Charles Gairdner Hospital.  Passion for rugby; medical history; medical education; and asynchronous learning #FOAMed evangelist. Co-founder and CTO of Life in the Fast lane | Eponyms | Books | Twitter |

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