Homans sign
（重定向自Homan sign）
In medicine, Homans' sign (sometimes spelled as Homans sign) or the dorsiflexion sign is considered a sign of deep vein thrombosis (DVT). It was defined by John Homans in 1941 as discomfort behind the knee on forced dorsiflexion of the foot. After surgeons discovered many examples of a false-positive Homans' sign, Homans redefined it in 1944, stating that "discomfort need have no part in the reaction.", including increased resistance, involuntary flexure of the knee or pain in the calf to forced dorsiflexion as positive responses.