All of the following infrahyoid muscles are supplied by the ansa cervicalis EXCEPT:

• A Sternohyoid
• B Sternothyroid
• C Omohyoid
• D Thyrohyoid ✓

Explanation

The ansa cervicalis (D1, D2, D3) supplies sternohyoid, sternothyroid, omohyoid and both bellies of geniohyoid is separate, but thyrohyoid is supplied by fibres from D1 that travel briefly with the hypoglossal nerve and leave it as a distinct branch to that muscle. This is why thyrohyoid escapes paralysis when the ansa is cut during neck dissection, making option D the single exception.

Reference: Gray's Anatomy: The Anatomical Basis of Clinical Practice, 42nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.