THN Attachments

External Intercostal

Rib to rib orientated from superior-lateral to inferior-medial

(orientated: down and in)

Internal & Innermost Intercostal

Rib to rib orientated from superior-medial to inferior-lateral

(down and out)

Transversus Thoracis

O: Posterior sternum

I: Costal cartilage

Diaphragm

O: Xiphoid process, inner surface of the lower ribs & costal cartilages, and lumbar vertebrae via cruca

I: Central Tendon

Buccinator

O: Alveolar processes of maxilla & mandible, pterygoid hamulus & pterygomandibular raphe

I: Angle of mouth

Depressor Anguli Oris

O: Mandible

I: Angle of mouth

Depressor Labii Inferioris

O: Oblique line of mandible

I: Skin of lower lip

Frontalis

O: Superficial fascia of the eyebrows

I: Epicranial aponeurosis

Levator Labii Superioris

O: Inferior orbital margin

I: Lateral aspect of the upper lip

Nasalis

O: Maxilla lateral & inferior

I: Nasal notch to the bridge & ala of the nosa

Orbicularis Oculi

O: Orbital margin & medial palpebral ligament

I: Superficial fascia of the eyelid

Orbicularis Oris

O: Angle of mouth

I: Superficial fascia of the upper lip

Platysma

O: Lower order of the mandible

I: Superficial fascia of the skin of the neck overlying the clavicle

Zygomaticus Major

O: Zygomatic bone

I: Angle of mouth

Inferior Oblique

O: Maxilla lateral to the nasalacrimal groove

I: Inferolateral, posterior aspect of the sclera

Inferior Rectus

O: Common tendinous ring

I: Inferior aspect of the sclera

Levator Palpebrae Superioris

O: Inferior aspect of the lesser wing of the sphenoid

I: Tarsus and skin of the upper lip

Medial Rectus

O: Common tendinous ring

I: Medial aspect of the sclera

Superior Rectus

O: Common tendinous ring

I: Superior aspect of the sclera

Lateral Rectus

O: Common tendinous ring

I: Lateral aspect of the sclera

Superior Oblique

O: Superomedial, posterior aspect of the orbit

I: Superolateral, posterior aspect of the sclera passing around the trochlea (superomedial, anterior aspect of the orbit)

Masseter

O: Zygomatic arch

I: Angle of the mandible & lateral aspect of the ramus

Temporalis

O: Temporal fossa
I: Coronoid process & anterior border of the ramus of the mandible

Lateral Pterygoid

O: Infratemporal surface of the sphenoid & lateral surface of the lateral pterygoid plate

I: Neck of the mandible & TMJ disc

Medial Pterygoid

O: Medial surface of the lateral pterygoid plate & adjacent maxilla

I: Medial aspect of the angle of the mandible

Anterior Digastric

O: Digastric fossa of mandible

I: Intermediate tendon (greater cornu of hyoid)

(inferior border of mandible near symphysis to intermediate tendon & body and cornu of hyoid)

Posterior Digastric

O: Temporal mastoid notch

I: Intermediate tendon (greater cornu of hyoid)

(mastoid process to intermediate tendon & body and cornu of hyoid)

Geniohyoid

O: Inferior genial tubercle of mandible

I: Anterior aspect of the body of hyoid (median ridge of mandible to body of hyoid)

Longus Capitis

O: Anterior tubercles of the transverse processes of cervical vertebrae

O: Basilar occipital bone

Longus Colli

O: Cervical vertebral bodies
I: Cervical vertebral bodies & transverse processes

Mylohyoid

O: Mylohyoid line of the mandible

I: Midline raphe & anterior aspect of body of hyoid

Omohyoid

O; Superior border of the scapula medial to scapular notch

I: Lateral aspect of the hyoid passing through an intermediate tendon sling loosely associated with the clavicle & 1st rib

Anterior Scalene

O: Anterior tubercles of middle cervical vertebrae

I: Scalene tubercle of the 1st rib

Middle Scalene

O: Transverse processes of cervical vertebrae
I: 1st rib

Posterior Scalene

O: Lower cervical transverse processes

I: 2nd rib

Sternocleidomastoid

O: Lateral aspect of mastoid process & superior nuchal line

I: Manubrium & medial 1/3 of clavicle

Sternohyoid

O: Posterior side of proximal clavicle & adjacent manubrium

I: Inferior border of body of hyoid

Sternothyroid

O: Posterior aspect of manubrium & costal cartilage of 1st rib

I: Thyroid lamina

Stylohyoid

O: Styloid process of temporal bone

I: Body of hyoid bone

Thyrohyoid

O: Thyroid lamina

I: Greater horn of hyoid bone

Cricothyroid

O: Cricoid cartilage

I: Thyroid cartilage

Splenius Capitis

O: Ligamentum nuchae, lower cervical & upper thoracic spinous processes

I: Lateral 1/3 of superior nuchal line

Longissimus Capitis

O: Upper thoracic transverse processes

I: Posterior margin of mastoid process

Semispinalis Capitis

O; Upper thoracic & cervical transverse processes

I: Occipital bone between inferior & superior nuchal lines

Rectus Capitis Posterior Major

O: Spinous process C2

I: Lateral aspect inferior nuchal line

Rectus Capitis Posterior Minor

O: Tubercle on posterior arch C1

I: Medial aspect inferior nuchal line

Obliquus Capitis Inferior (Inferior Oblique)

O: Spinous process of C2

I: Transverse process of C1

Obliquus Capitis Superior (Superior Oblique)

O: Transverse process of C1

I: Area between superior and inferior nuchal line on occipital bones