Oppenheim's sign is dorsiflexion of the great toe elicited by irritation downward of the medial side of the tibia. It is one of a number of Babinski-like responses.The sign's presence indicates damage to the pyramidal tract.
It is named after Hermann Oppenheim.H. Oppenheim. Zur Pathologie der Hautreflexe der unteren Extremitäten. Monatsschrift für Psychiatrie und Neurologie, 1902, 12: 421-423.
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