Prime movers of the head neck and trunk

interspinales

Extension of the spine

Erector spinae

I Love Spaghetti Iliocostalis longissimus spinalis Bilaterally: Extension of the neck and trunk Unilaterally: Lateral flexion of the neck and trunk

serratus posterior superior

Raises ribs to increase thoracic cavity (Part of the respiratory muscles)

splenius cervicis

Rotation of the neck and lateral bending to the same side Bilarterally: extension of the neck

Transversospinalis

Semispinales, multifidus, and rotatores (superficial to deep) Bilaterally: extend the neck and trunk unilaterally: rotate neck and trunk to opposite side (deeper muscles span one or two vertebra while superficial ones span more)

Scalenes (uneven)

anterior, medius, and posterior Bilaterally raise first 2 ribs during forced inspiration or assist neck flexion Unilaterally: assist neck lateral bending to the same side brachial plexus passes between anterior and middle

spinalis

attach to nuchal ligament and spinal processes of the cervical and thoracic vertebrae. The portion of this group that attaches to the occiput also attaches to the transverse processes of the cervical vertebrae. Prime movers in trunk extension.

longissimus

attach to the transverse processes from the occiput to the sacrum. They can extend and laterally bend the neck and trunk.

sternocleidomastoid

bilaterally: flexion of the neck unilaterally: lateral flexion, rotation of the head to opposite side

Prime movers for Respiration

diaphragm, internal and external intercostals

serratus posterior inferior

draws ribs outward and downward to counteract the inward pull of the diaphragm (Part of the respiratory muscles)

Prime movers for trunk extension (3)

erector spinae, transversospinalis, interspinales

Prime movers for trunk contralateral rotation

external oblique, transversospinalis

Intercostals

external, internal, innermost intercostals They are the thoracic continuation of the external and internal obliques they are the anterior rami of the thoracic nerves

Splenius capitis

inserts deep to the sternocleidomastoid. Bilaterally extend the head and neck. Unilaterally rotate and laterally bend the face to the same side.

Prime movers for compression of the abdomen (4)

internal and external oblique, rectus abdominis and transverse abdominis.

Prime movers for trunk ipsilateral rotation

internal oblique

Intertransversarii

lateral flexion of the spine

Prime movers for TMJ depression (1)

lateral pterygoid

Prime movers for tmj protrusion (2)

lateral pterygoid, medial pterygoid

Accesory muscles for forced inspiration (4)

levator scapula, upper trapezius, rhomboids and pectoralis minor (active muscles are external intercostals and diaphragm)

prevertebral muscles

longus capitis (flex head) longus colli (flex neck) rectus capitis anterior (flex head) rectus capitis lateralis (laterally bend the head)

Prime movers for contralateral lateral deviation (2)

medial and lateral pterygoid

Iliocostalis

most lateral of the erector spinae and attach primarily to the ribs making them excellent at lateral bending and extension of the trunk

suprahyoid group

mylohyoid geniohyoid stylohyoid digastric

Suboccipital muscles

obliquus capitis superior (extension) obliquus capitis inferior (extension, Lateral bending, and rotation to the same side) rectus capitis posterior major (extension) rectus capitis posterior minor (extension, lateral bending, rotation to the same side)

quadratus lomborum

originates in the iliac crest and insterts into the last rib (t12) and transverse processes of the lumbar vertebrae (l1-l5). Laterally bends the trunk and also can elevate the pelvis in a reversal of muscle action.

muscles of the mouth and hyoid bone

platysma (draw lower lip down and out), suprahyoid group (suspend hyoid bone), and infrahyoid group (lower hyoid bone)

Prime movers for head flexion

prevertebral group (longus colli, longus capitis, rectus capitis anterior and and lateralis).

Prime movers for trunk lateral bending (5)

quadratus lomborum, erector spinae, internal and external oblique, intertransversarii.

Prime movers for trunk flexion (3)

rectus abdominis, external oblique, internal oblique

accessory muscles for forced expiration

rectus abdominis, external oblique, internal oblique, transverse abdominis superior, quadratus lomborum, serratus posterior inferior, (active muscles are internal intercostals)

Prime movers for neck lateral bending (6)

scm, splenius capitis and cervicis, scalenes, erector spinae, intertransversarii

Prime movers for neck contralateral rotation (2)

scm, transversospinalis

Prime movers for neck ipsilateral rotation (2)

splenius capitis and cervicis

Prime movers for neck extension (5)

splenius capitis, splenius cervicis, erector spinae, transversospinalis, interspinales, (assistive scalenes and intertransversarii)

Prime movers for neck flexion

sternocleidomastoid

accessory muscles for deep inspiration (5)

sternocleidomastoid, pectoralis major, scalenes, levator costarum, serratus posterior superior (active muscles are external intercostals and diaphragm)

infrahyoid group

sternohyoid sternothyroid thyrohyoid omohyoid

Prime movers for head extension

suboccipital group -obliquus capitis superior and inferior, rectus capitis posterior major and minor

Prime mover for TMJ retrussion

temporalis (posterior fibers)

Prime movers for ipsilateral lateral deviation (2)

temporalis and masseter

Prime movers for TMJ elevation (3)

temporalis, masseter, medial pterygoid