Hyoid bone: the U-shaped bone that supports the neck
Quick facts
- Shape
- U-shaped bone, with no articulation with another bone.
- Location
- Anterior neck, above the thyroid cartilage and below the mandible.
- Function
- Anchors the tongue and the suprahyoid and infrahyoid muscles; takes part in swallowing and speech.
- Relation to aesthetics
- Its position influences the cervicomental angle and the definition of the submental region.
The hyoid bone is a small, U-shaped bone in the anterior neck, just above the thyroid cartilage and below the mandible. It has an unusual feature: it does not articulate with any other bone. It hangs suspended by muscles and ligaments, and it is the anchor of the tongue and of several neck muscles.
What attaches to the hyoid?
The muscles that attach to it are divided into two groups. The suprahyoids connect it to the mandible and skull. The infrahyoids connect it to the sternum and thyroid. The digastric and the mylohyoid are among the best-known suprahyoids, and they form the floor of the submental region.
| Group | Examples | Role |
|---|---|---|
| Suprahyoids | Digastric, mylohyoid | Raise the hyoid and lower the mandible |
| Infrahyoids | Sternohyoid, omohyoid | Stabilize or lower the hyoid |
| Tongue | Base of the tongue | Attaches to the hyoid |
See also the entry on the suprahyoid and infrahyoid muscles.
Why does the hyoid matter in aesthetics?
The hyoid is a deep reference for the cervicomental angle, the one formed between the submental surface and the neck. Its height and position influence the look of the region:
- Higher hyoid: tends to be associated with a more defined cervicomental angle.
- Lower hyoid: may be associated with a more open angle and less definition of the line between chin and neck.
- Other layers: submental fat, subplatysmal fat, the platysma and the skin also play a role. For that reason, definition of the region does not depend on the bone alone.
The hyoid cannot be changed with an aesthetic treatment, and that limitation is what the professional must explain. When the patient expects a crisp jawline without considering bone position, the conversation needs to include what is possible and what depends on anatomy.
What does the hyoid teach about safety?
The submental region and neck have important structures: vessels, glands and the thyroid cartilage, just below the hyoid. For that reason, procedures in this area call for care and knowledge of anatomy. Management and technique are at the discretion of the qualified professional, according to the rules of their professional council (in Brazil).
Also called: hyoid bone, os hyoideum.
Frequently asked questions
Does the hyoid bone influence the look of a double chin?
Yes, in part. When it sits lower, the angle between chin and neck tends to be more open and the definition of the submental region lower. Fat and skin also play a role.