Trousseau sign is the name of two distinct phenomena observed in clinical medicine. Both are attributed to Armand Trousseau:

Trousseau sign of latent tetany (aka Carpopedal spasm)

---

In a patient with hypocalcemia, carpal spasm may be elicited by occluding the brachial artery. To perform the maneuver, a blood pressure cuff is placed around the arm and inflated to a pressure greater than the systolic blood pressure and held in place for 3 minutes. If carpal spasm occurs, manifested as flexion at the wrist and metacarpophalangeal joints, extension of the distal interphalangeal and proximal interphalangeal joints, and adduction of the thumb and fingers, the sign is said to be positive and the patient likely has hypocalcemia. This sign may become positive before other gross manifestations of hypocalcemia such as hyperreflexia and tetany, but is generally believed to be less sensitive than the Chvostek sign for hypocalcemia.

Trousseau sign of malignancy

---

Referred to as "Trousseau's syndrome" to distinguish it from the above.

Some malignancies, especially adenocarcinomas of the pancreas and lung, are associated with hypercoagulability for reasons that remain unclear. In patients with malignancy-associated hypercoagulable states, the blood may spontaneously form clots in the portal vessels, the deep veins of the extremities, or the superficial veins anywhere on the body. When recurrent clots form in different superficial veins around the body, this is described as migratory thrombophlebitis. Dr. Armand Trousseau first described this finding in himself; he was subsequently found to have pancreatic cancer.

Eponymous medical signs