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    Related Topics

    From Musculoskeletal System

    Posterior Longitudinal Ligament
    Spinal ligament running along the back of the vertebral column.
    Scapula
    Shoulder blade providing attachment for muscles of the upper limb.
    Skull
    Bony structure of the head that encases the brain.
    Brachioradialis
    Muscle responsible for forearm flexion.
    Fibula
    Smaller bone in the lower leg, located alongside the tibia.
    Deltoid
    Shoulder muscle responsible for arm abduction.
    Cervical Vertebrae (C1 - C7)
    Vertebrae in the neck region (C1-C7).
    Ulna
    Forearm bone on the pinky side.
    Ethmoid Bone
    Bone forming part of the nasal cavity and the orbit.
    Ilium
    Uppermost and largest part of the hip bone.
    Parietal Bones
    Bones forming the sides and roof of the skull.
    Gluteus Maximus
    Largest muscle in the buttocks responsible for hip extension.
    Obliques (External and Internal)
    Muscles responsible for torso rotation.
    Quadriceps Tendon
    Tendon that connects the quadriceps to the patella.
    Metacarpals (5 bones)
    5 bones forming the palm of the hand.
    Pivot Joints
    e.g., atlanto-axial joint
    Nasal Bones
    Bones forming the bridge of the nose.
    Ball-and-Socket Joints
    e.g., shoulder, hip
    Soleus
    Calf muscle responsible for plantarflexion of the foot.
    Masseter
    Muscle that elevates the mandible.
    Triceps Brachii
    Muscle responsible for elbow extension.
    Maxillae
    Upper jaw bones that house the teeth and form part of the orbit.
    Coracoacromial Ligament
    Ligament that connects the acromion to the coracoid process.
    Palatine Bones
    Bones forming part of the hard palate and nasal cavity.
    Ellipsoidal (Condyloid) Joints
    e.g., wrist

    Hyoid Bone

    Reviewed by our medical team

    U-shaped bone in the neck that supports the tongue.

    1. Overview

    The hyoid bone is a small, U-shaped bone located in the anterior neck. Uniquely, it is the only bone in the human body that does not articulate directly with any other bone. Instead, it is suspended in place by muscles and ligaments. The hyoid serves as a crucial anchoring structure for the tongue, supports the larynx (voice box), and plays a vital role in swallowing and speech. It is often studied in anatomy due to its functional and forensic significance.

    2. Location

    The hyoid bone is located in the anterior midline of the neck:

    • Superiorly: Lies below the mandible (lower jaw).

    • Inferiorly: Positioned above the thyroid cartilage (Adam's apple).

    • At the level of: Cervical vertebra C3 in a neutral position.

    • Surrounding structures: Connected to the floor of the oral cavity, pharynx, larynx, and epiglottis by muscle and ligament attachments.

    3. Structure

    The hyoid bone has a characteristic horseshoe or U-shape and consists of three parts:

    • Body: The central part, thick and rectangular in shape.

    • Greater horns (cornua): Project posteriorly and laterally from the body; attachment sites for several muscles (e.g., middle constrictor, hyoglossus).

    • Lesser horns (cornua): Small, conical projections superior to the body; serve as attachment points for the stylohyoid ligament.

    The hyoid bone is made of compact bone and has a dense outer cortex with a medullary cavity. It is anchored by the suprahyoid and infrahyoid muscle groups.

    4. Function

    The hyoid bone serves as a dynamic anchor and support for several functions:

    • Supports the tongue: Acts as the base for tongue movement, aiding in speech and swallowing.

    • Assists in swallowing: Serves as a platform for the elevation of the larynx and movement of the pharynx during deglutition.

    • Facilitates speech: Supports vocalization by maintaining airway patency and stabilizing the larynx.

    • Acts as a muscle attachment site: Anchors over a dozen muscles involved in jaw, neck, and throat movement.

    5. Physiological role(s)

    Despite its small size, the hyoid bone plays critical physiological roles:

    • Respiration: Keeps the airway open by supporting the upper respiratory tract and indirectly preventing airway collapse during breathing.

    • Speech modulation: Works with the laryngeal cartilages and vocal cords to modulate pitch and volume.

    • Swallowing reflex: Coordinates with pharyngeal muscles to initiate and complete the swallowing mechanism safely.

    • Muscle coordination: Coordinates movements between the jaw, tongue, and larynx, critical in chewing and phonation.

    6. Clinical Significance

    The hyoid bone is associated with various clinical and forensic considerations:

    • Hyoid fracture:

      • Rare in accidental trauma but may occur in cases of manual strangulation or hanging, making it significant in forensic investigations.

    • Dysphagia (difficulty swallowing):

      • Can result from dysfunction of muscles attached to the hyoid, particularly in neurological or post-surgical conditions.

    • Speech disorders:

      • Abnormal positioning or injury to the hyoid can affect tongue movement and vocal cord tension, impacting speech clarity.

    • Thyroglossal duct cysts:

      • Embryological remnants can form cysts near the hyoid, often requiring surgical excision that includes part of the hyoid bone (Sistrunk procedure).

    • Obstructive sleep apnea:

      • Inferior positioning of the hyoid is sometimes associated with upper airway obstruction, contributing to sleep apnea.

    Did you know? Your skeleton is 5 times stronger than steel.