Muscles Flashcards
Control limb movement
Superficial extrinsic
Muscles that are extrinsic
Trapezius, latissimus dorsi, levator scapulae, rhomboids
Classified as posterior axioappendicular muscles that connect the axial skeleton
to the pectoral girdle and humerus.
Superficial extrinsic
Control respiratory movements
Intermediate extrinsic
Intermediate extrinsic
Serratus posterior superior and inferior
deep back and back proper
Intrinsic
Deep muscles (superficial layer)
Splenius muscles
• Splenius capitis
• Splenius cervicis
Deep muscles (intermediate layer)
Erector spinae muscles • Iliocostalis, Longissimus, Spinalis
Deep layer
Transversospinales muscle group
• Semispinalis, Multifidus, Rotatores • Deep Minor layer- Interspinalis, Intertransversarii, levator costarum
Trapezius
• Origin: Greater external occipital
protuberance, Superior nuchal line, Nuchal ligament, and Spinous processes of C7-T12
• Insertion: Lateral third of clavicle and
Spine of the scapula
• Innervation: Spinal accessory nerve
Action of the upper trapezius
Elevation and upward rotation of scapula
Action of the middle trapezius
Retraction of the scapula
Action of the Lower trapezius
Depression and upward
rotation of the scapula
Latissimus dorsi
Origin: Thoracolumbar fascia
• Insertion: Intertubercular groove(sulcus) of
the humerus
• Innervation: Thoracodorsal Nerve
(C6,C7,C8)
• Action: Adduction, Extension, and Internal
rotation of the humerus
• Blood supply: Thoracodorsal artery
Levator scapulae
• Origin: Posterior tubercles of the
transverse processes of C1-C4
• Insertion: Medial border and
superior angle of the scapula
• Innervation: Dorsal scapular nerve
(C4-5) and sometimes cervical nerves (C3-4)
• Action: Elevates and downward
rotates the scapula
• Plays role in head posture
Rhomboid major
Origin: Spinous process of T2-T5
• Insertion: Medial border of scapula
• Innervation: Dorsal scapular nerve
(C4-C5)
• Action: Retracts and downward
rotates the scapula
• Fixes scapula to thorax • Blood supply: Dorsal Scapular
artery
Rhomboid minor
• Origin: Nuchal ligament and Spinous
process of C7-T1
• Insertion: Medial border of scapula • Innervation: Dorsal scapular nerve
(C4-C5)
• Action: Retracts and downward
rotates the scapula
• Fixes scapula to thorax • Blood supply: Dorsal Scapular artery
Serratus posterior superior
• Origin: Nuchal ligament and Spinous
process of C7-T3
• Insertion: Superior borders of ribs 2-4
• Innervation: Intercostal nerves T2-T4
• Action: Elevate ribs (Proprioception)
Serratus Posterior Inferior
• Origin: Spinous process of T11-L2
• Insertion: Inferior borders of ribs 8-12
• Innervation: Thoracic spinal nerves
T9-T12
• Action: Depress ribs (Proprioception)
Splenius means
Bandage
Run deep to the trapezius and rhomboids
Splenius
Splenius capitis
Origin: Nuchal ligament and Spinous
process of C3-T3 • Insertion: Mastoid process of
occipital bone
• Innervation: Dorsal rami of middle
cervical spinal nerves
• Action: Rotation and lateral side
bending (unilaterally)
• Extension (bilaterally)
Splenius cervicis
Origin: Spinous process of T3-T6
• Insertion: Posterior tubercules of
transvers processes of C1-C4
• Innervation: Dorsal rami of middle
cervical spinal nerves
• Action: Cervical rotation and lateral
side bending (unilaterally)
• Extension (bilaterally)
Iliocostalis muscles =
Most lateral
Iliocostalis lumborum
• Origin: Common tendinous origin to
sacrum and posterior iliac crest
• Insertion: Lower border of the rib
angles of 6-12
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilization (bilaterally)
Ilicostalis thoracis
• Origin: Upper border of ribs 6-12 (medial to
lumborum)
• Insertion: Lower border of the rib angles
of 1-6
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilization (bilaterally)
Iliocostalis cervicis
Origin: Upper border of ribs 1-6 (medial to
thoracis)
• Insertion: Transverse process of C4-C6 (we’ll
find in spring)
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture, and
stabilization (bilaterally)
Longissimus thoracis
• Origin: Common tendinous origin to
sacrum and posterior iliac crest • InserWon: Transverse processes of all
thoracic vertebrae, and medial to rib
angles
• InnervaWon: Posterior rami of spinal
nerves
• AcWon: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilizaWon (bilaterally)
Longissimus cervicics
• Origin: Transverse process of T1-T5
• Insertion: Transverse processes of all
C2-C6
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect
posture, and stabilization (bilaterally)
Longissimus capitis
• Origin: Transverse process and articular
processes of lower cervical and upper thoracic vertebrae
• Insertion: Posterior aspect of mastoid
process
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilization (bilaterally)
Spinalis thoracis
• Origin: Common tendinous origin to
sacrum and posterior iliac crest • Insertion: Spinous process of T3-T9
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture, and
stabilization (bilaterally)
Spinalis cervicis
• Origin: Spinous process of C6-T2
• Insertion: Spinous process of C2-C4
• Innervation: Posterior rami of spinal
nerves
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilization (bilaterally)
Spinalis capitis
Origin: Spinous process of lower cervical
and upper thoracic vertebrae
• Insertion: Between superior and inferior
Nuchal lines of the occipital bone (follows WILL FIND the fibers of semispinalis capitis)
• Innervation: Posterior rami of spinal
nerves IN SPRING
• Action: Lateral side bending (unilaterally)
• Extension, maintain erect posture,
and stabilization (bilaterally)
Transversospinales muscle group
Semispinalis, Multifidus, Rotatores
Semispinalis thoracis
Origin: Transvers process of T6-T12
• Insertion: Spinous process of upper thoracic
lower cervical vertebrae
• Innervation: Posterior rami of spinal nerves
• Action: Rotation (unilaterally)
• Extension of back and neck (bilaterally)
• Posture
Semispinalis cervicis
Origin: Transvers process of T1-T6
• InserWon: Spinous process of C2-C5
• InnervaWon: Posterior rami of spinal nerves
• AcWon: RotaWon (unilaterally)
• Extension of back and neck (bilaterally)
• Posture
Semispinalis capitis
Origin: Transvers process of T1-T6 and
articular process of C4-C7
• Insertion: Between superior and inferior
nuchal lines of occipital bone (on head)
• Innervation: Posterior rami of spinal
nerves •
Action: Rotation (unilaterally)
• Extension of back and neck (bilaterally)
• Posture
Multifidus
Origin:
• Cervical: Articular processes of lower vertebrae
• Thoracic: Transverse processes of thoracic
vertebrae
• Lumbar: PSIS, deep portion of common
tendinous origin of erector spinae, and Lower
portion of dorsal sacrum
• (This is what we will spend most of our time
seeing in the lab and working on in the clinic)
Multifidus
Insertion: Spinous processes of L5-C2
• (whole back, but will skip 1-3 segments
based on location)
• Innervation: Posterior rami of spinal
nerves
• Action:
• Bilateral extension •
Controls/stabilizes lateral flexion
eccentrically
• Unilaterally rotates vertebral
bodies
Rotarores short and long
• Origin: Transvers process of a vertebrae
• Insertion: Inserts on base of spinous
process
• Short: Vertebrae immediately above
• Long: Skips 1 vertebrae
• Action: Rotation (unilaterally)
• Extension of back and neck (bilaterally)
• Posture
Levator costorum
• O&I: Transverse process to rib below
• Brevis: 1 TP above
• Longus: 2 TPs above
Action- elevate rib
Interspinalis
• O&I: Between Spinous Processes
• Action: Extension
Intertransversarii
• O&I: Between Transverse Processes
• Action: Side bending
