Trousseau's Sign
Introduction
This sign is named after Dr. Armand Trousseau, a French internist. He is credited with its discovery in 1861.[1] Its presence is suggestive of hypocalcaemia.[1]
Purpose
Trousseau's sign is a significant clinical indicator of hypocalcaemia, characterised by a carpopedal spasm of the hand and wrist muscles, elicited by inflating a blood pressure cuff around the arm above the patient's systolic pressure.[2]
Technique
Step 1: Place the sphygmomanometer cuff around the patient's arm in the same manner as you would for a routine blood pressure measurement.
Step 2: Slowly inflate the cuff until the pressure reaches 20 mmHg above the patient's systolic blood pressure.
Step 3: Maintain the inflated cuff at that pressure and wait for 2 to 3 minutes.
Step 4: Carefully observe the patient's hand for any abnormal posturing or carpopedal spasm. Note that this spasm results from ischaemia induced by compression through the inflated cuff.
Step 7: Document your findings and immediately notify the physician if a positive sign is observed, as it may indicate hypocalcaemia, hypomagnesemia, or metabolic alkalosis.[3][4]
Interpretation
A positive Trousseau's sign is indicated if a carpopedal spasm appears, which is characterised by:
- Flexion of the wrist
- Flexion of the thumb
- Flexion of the metacarpophalangeal joints
- Hyperextension of the Interphalangeal joints
Evidence
Trousseau's sign demonstrates superior diagnostic accuracy, with a sensitivity of 94% in patients with hypocalcaemia and a specificity of 99%, as it is observed in fewer than 1% of individuals with normal calcium levels.[6]
References
- ↑ 1.0 1.1 Alam A. Trousseau’s sign. Case Reports in Clinical Medicine. 2013 Aug 2;2(5):326-7.
- ↑ Zeleke, A.A. (2025) Chvostek’s sign and trousseau’s sign as clinical indicators of tetany, Klarity Health Library. Available at: https://my.klarity.health/chvosteks-sign-and-trousseaus-sign-as-clinical-indicators-of-tetany/ (Accessed: May 15, 2026).
- ↑ Rehman HU, Wunder S. Trousseau sign in hypocalcemia. CMAJ. 2011 May 17;183(8):E498.
- ↑ Burke TA, Almanza CM, Hager LC, Casadesus D, Almanza C, Hager L. Severe Hypocalcemia Leading to Trousseau's Sign. Cureus. 2025 Mar 11;17(3).
- ↑ Dr. Vivek Dudeja ENT SPECIALIST. Trousseau's sign of latent tetany seen in hypocalcemia. 2017. [online] Available at: <https://www.youtube.com/watch?v=e03EKe9peUo> [Accessed 21 August 2020].
- ↑ Jesus JE, Landry A. Chvostek's and Trousseau's Signs. New England Journal of Medicine. 2012 Sep 13;367(11):e15.