A novel highly specialized functional flap: omohyoid inferior belly muscle

Aim: There is no previous description on the anatomy of the inferior belly of the omohyoid muscle. This muscle has specific morphological characteristic that make it appealing when solving specialized reconstructive problems. Our objective is to describe the microsurgical anatomy of the inferior belly from the omohyoid muscle.Methods: Supraclavicular bilateral dissection in 5 anatomic models (fresh human cadavers). Measurements were taken with a millimetric caliper. Statistical analysis was performed with measures of central tendency.Results: Eight muscles were dissected in 5 anatomic models. Average dimensions were: 93 mm long, 12 mm wide, and 7.5 mm thickness. The vascular pedicles showed great anatomical variability. In 2 flaps (1 model) irrigation came exclusively from transverse cervical vessels, in the remaining models the pedicles came directly from the subclavian vessels; 2 flaps had an accessory minor pedicle from the transverse cervical vessels. The diameter of all vascular pedicles was less than 0.8 mm, with an average length of 22.3 mm. The nerve pedicle came from ansa cervicalis in all flaps, with an average length of 27.8 mm.Conclusion: Based on the findings we conclude that omohyoid muscle could be a reconstructive option when small functional flaps are required, such as facial reanimation surgery, sphincters, ptosis and vocal cord reconstruction, and blink restoration surgery although more anatomical studies are required to determine the microsurgical feasibility, excursion and strength of the muscle, and axonal load in this new myofunctional flap