Muscle Name | Origin | Insertion | Action |
Orbicularis Oris | Maxillary Bone; Mandible | Lips | Closes and protrudes lips as in speaking, kissing, and whistling |
Buccinator | Maxillary Bone; Mandible | Blends with Fibers of Orbicularis Oris | Compresses cheek while whistling or blowing |
Zygomaticus Major | Zygomatic Bone | Angle of Mouth | Raises lateral corner of mouth for smiling |
Zygomaticus Minor | Zygomatic Bone | Upper Lip | Raises upper lip |
Levator Labii Superioris | Inferior Aspect of Bony Orbit | Blends with Fibers of Orbicularis Oris | Elevates upper lip; dilates nostrils |
Depressor Anguli Oris | Anterolateral Surface of Mandible | Skin at Angle of Mouth | Depresses angle of mouth |
Mentalis | Anterior Surface of Mandible | Skin of Chin | Protrudes lower lip; wrinkles skin at chin |
Masseter | Zygomatic Arch | Lateral Surface of Mandibular Ramus | Elevates mandible to close jaw; protrudes mandible |
Temporalis | Temporal Bone | Coronoid Process of Mandible | Elevates mandible to close jaw; retrudes mandible |
Hyoglossus | Hyoid Bone | Tongue | Depresses Tongue |
Sternocleidomastoid | Manubrium; Medial One-Third of Clavicle | Mastoid process; occipital bone near mastoid process | flexion and lateral flexion of neck; rotates head so that face is turned superiorly and to the opposite side |
Mylohyoid | Inferior Margin of Mandible at the Chin | Hyoid Bone | Elevates hyoid bone, tongue, and floor of mouth during swallowing and speaking |
Sternohyoid | Mandubrium | Hyoid Bone | Depresses larynx and hyoid bone during swallowing |
Depressor Labii Inferioris | Anterolateral surface of mandible | Skin of lower lip | Depresses lower lip |
Thyrohyoid | Thyroid cartilage of larynx | Hyoid Bone | Depresses hyoid bone; elevates larynx |
Splenius | Spinous processes of inferior cervical and superior thoracic vertebrae | Mastoid Process, occipital bone and transverse process of superior cervical vertebrae | Laterally flexes, rotates, and extends head and neck |
Scalenes (Posterior, Middle, and Anterior) | Transverse processes of cervical vertebrae | First and second ribs | Lateral flexion of neck, elevates ribs 1 and 2 during forced inspiration |
Levator Scapulae | Transverse processes of superior 4 cervical vertebrae | Medial border of scapulae near superior angle | Elevates scapula; inferior rotation of scapula |
External Intercostals | Inferior border of superior rib | Superior border of inferior rib | Elevates ribs during normal inspiration |
Internal Intercostals | Superior border of inferior rib | Inferior border of superior rib | Depresses the ribs during forced expiration |
Rectus Abdominus | Pubic crest; pubic symphysis | Xiphoid process, costal cartilages of ribs 5-7 | Flexion of vertebral column; stabilizes pelvis during walking, increases intraabdominal pressure during forced expiration |
External Oblique | External surfaces of superior 8 ribs | Linea alba; pubic crest, pubic tubercle; iliac crest | Rotation and lateral flexion of trunk; increases intraabdominal pressure during forced expiration |
Internal Oblique | Thoracolumbar fascia; iliac crest; inguinal ligament | Linea alba; pubic crest; inferior 3 or 4 ribs | Rotation and lateral flexion of trunk; increases intraabdominal pressure during forced expiration |
Transversus Abdominis | Thoracolumbar fascia; inguinal ligament; costal cartilages of inferior 6 ribs; iliac crest | Linea alba; pubic crest | Increases intraabdoninal pressure during forced expiration |
Nasalis | Maxilary Bone; Alar cartilage of Nose | Bridge of Nose | Compresses and dilates nostrils |
Orbicularis Oculis | Medial Aspect of Bony Orbit | Skin around Eyelids | Closes eyelid; acts during squinting and blinking |