It can be hypothecated that, suprahyoid and infrahyoid muscles form a continuous band of muscles extending from base of the skull to sternum with intermittent attachment to hyoid bone.
Although numerous reports are cited in literature regarding variations in both the suprahyoid and infrahyoid muscles, we did not find similar case being reported in the literature.
Conditioning of the prosthesis with a solid titanium endoprosthetic tube under the infrahyoid muscles (day 0).
After placing the animal in the supine position, we performed a cervicotomy with a midline vertical incision, allowing access to the infrahyoid muscles, which we separated from the tracheal axis.
Conditioning of the porous titanium prosthesis with a solid titanium endoprosthetic tube under the infrahyoid muscles (day 0) for 60 days.
The infrahyoid muscles
were then closed to recreate the anatomic plane.
There are another three suprahyoid muscles: the geniohyoid, stylohyoid and mylohyoid, which are also inserted in the hyoid bone and, together with the digastric muscle, anchor this bone against the traction of the infrahyoid muscles
(Lockhart et al.).
As a consequence, exaggerated tension of the supra- and infrahyoid muscles in the dorsocaudal direction is produced, which promotes an increase in tongue muscle tension that leads to imprecise and slurred speech articulation.
An exaggerated tension of the supra- and infrahyoid muscles and a decrease in the suboccipital distance between C0-C1  would be added to this.
From the different types of variations in the infrahyoid muscles, the muscles extending between clavicle and hyoid bone were classified as cleidohyoid muscles by Loth as early as 1912 (7).
Omohyoid differs from the other three infrahyoid muscles (sternohyoid, sternothyroid, and thyrohyoid) in its course.
Flap elevation began at the midline and the infrahyoid muscle
group was dissected up to the fascia of the thyroid gland.