Abstract
Accessory muscles are rare anatomical variants which may have clinical implications. Variations of the muscles in the infrahyoid region assume clinical significance during diagnostic procedures and surgical operations in the region of neck. An unusual muscle "Cleidohyoideus accessorius" was found in the infra hyoid region bilaterally during routine dissection of neck region in an adult male cadaver. On both the sides muscle had its origin from the superior surface of the middle one third of the clavicle. The muscle coursing upward, lateral to the sternohyoid, was inserted into the hyoid bone. The other infra hyoid muscles including omohyoid were intact and in their typical form. The accessory muscle received its nerve supply from ansa cervicalis. Here we report a variation of rare occurrence, a case of bilateral accessory muscle "Cleidohyoideus accessorius", its embryological and clinical considerations are being reviewed here.