Rosh Emergency Medicine Practice Test

Which physical exam finding is the most specific for hypocalcemia?

1. Chvostek sign

2. Hutchinson sign

3. Queen Anne sign

4. Trousseau sign

The correct answer is: Trousseau sign

The most specific physical exam finding for hypocalcemia is Trousseau sign. This sign is demonstrated by inducing carpal spasm when a blood pressure cuff is inflated above the systolic pressure for several minutes. This phenomenon occurs due to increased neuromuscular excitability due to low calcium levels, reflecting the body's heightened response to stimuli in the context of hypocalcemia. The specificity of Trousseau sign comes from its strong association with hypocalcemia, as it directly reflects the impact of low calcium on neuromuscular function. In contrast, Chvostek sign, which involves tapping the facial nerve and observing twitching of facial muscles, is less specific as it can occur in other conditions that irritate the facial nerve or alter neuromuscular excitability. Other signs like Hutchinson and Queen Anne signs do not have established relevance to hypocalcemia and are not utilized in clinical practice to assess calcium levels. Therefore, Trousseau sign remains the most specific and clinically relevant finding for diagnosing hypocalcemia in patients.