Muscles of the Back (Quiz 3) Flashcards
The muscles of the superficial layer of the back (4)
- Trapezius
- Latissimus Dorsi
- Levator Scapula
- Rhomboids
The muscles of the intermediate layer of the back (2)
- Serratus Posterior Superior
- Serratus Posterior Inferior
3 Layers of the deep muscle of the back
- Superficial
- Intermediate
- Deep
Muscles of the superficial layer of the deep back muscles (2)
- Splenius Capitus
- Splenius Cervicis
Muscles of the intemediate layer of the Deep back muscles (3)
- Spinalis
- Longissimus
- Iliocostalis
5 muscles of the deep layer of the Deep back muscles
(3 Superomedial fibre direction, 2 Verticle fibre direction)
- Superomedial Fibre Direction
- Semispinalis
- Multifidus
- Rotatores
- Vertical Fibre Direction
- Interspinales
- Intertransversarii
2 muscles of the posterior Thorax
Accessory muscles of respiration
- Serratus Posterior Superior
- Serratus Anterior Superior
Group of back muscles that help to maintain posture and move the spine and head
Deep muscles (intrinsic muscles)
The 3 columns of muscles in the intermediate layer of the deep muscles of the back are collectively called?
The Erector Spinae Muscles
Aka Paraspinals
3 muscles in the deep layer of the back that have a superomedial fibre direction
Collectively called the Transversospinalis muscles
- Semispinalis
- Multifidus
- Rotatores
2 muscles in the deep layer of the back that have a verticle fibre direction
- Interspinals
- Intertransversarii
The groove between the Spinous process and the Transverse processes
Laminar Groove
Muscles found in the Laminar Groove
They attach from the TVPs to the SPs (of the superior vertebrae)
- Semispinalis
- Multifidus
- Rotatores
(Superomedial fibre direction, Deep layer of the deep back muscles)
Muscle deep to rhomboids, and superficial to erector spinae
Serratus Posterior Superior
Muscle deep to Latissimus Dorsi/Thoracolumbar Fascia, and superficial to the Erector Spinae muscles
Serratus Posterior Inferior
Medial Attachment: SPs of C7-T3
Lateral Attachment: Superior borders of ribs 2-5
Supermedial Fibre direction
Action: Elvation of ribs 2-5 (with forced inhalation)
Serratus Posterior Superior
Medial Attachment: SPs of T11-L2
Lateral Attachment: Lower 4 ribs (12-8)
Inferomedial fibre direction
Action: Draws ribs down and back (w/ forced expiration)
Serratus Posterior Inferior
Inferior Attachment: SPs of C4-T2
Superior Attachment: Mastiod process and lateral superior nuchal line
Action (Unilateral Contraction): Ipsilateral rotation
Action (Bilateral Contraction) Extension of the Neck
Splenius Capitis
Inferior Attachment: SPs of T3-T5
Superior Attachment: C1-C4 TVPs
Action (unilateral contraction): Ipsilateral Rotation
Action (bilateral contraction): Extension of the neck
Splenius Cervicis
Muscles that arise inferiorly from the Thoracolumbar fascia
Spread out in a superolateral direction
Subdivided into 3 columns of muscle on either side of the spine
(each column has 3 segments)
Intermediate layer of the Deep back muscles
The Muscles of the intermediate layer of the Deep back muscles, from medial to lateral
- Spinalis
- Longissimus
- Iliocostlis
A very thin muscle
Sits in the the Laminar Groove
Attaches to SPs
Spinalis
3 regions spinalis passes through
Thoracis (upper T-spine)
Cervicis
Capitis
Longest Column of the erector spinae
Attaches to TVPs
Longissimus
3 regions that Longissimus passes through
Throacis (T-Spine TVPs)
Cervicis (C-Spine TVPs)
Capitis (Mastiod Process)
Most lateral of the Erector Spinae muscles
Attaches to the angles of the ribs
Iliocostalis
3 regions Iliocostalis passes through
Lumborum (ribs 12-8)
Thoracis (ribs 7-1)
Cervicis (TVPs of C3-C6)
Actions of all erector spinae muscles
- unilateral
- bilateral
- Lateral flexion of the vertebral column
- Extension of the Vertebral column
Deep muscle that covers 1/2 of the spinal cord (skips 3-6 vertebrae)
Attaches superiorly to the occipital bone between the superior and inferior nuchal lines
Largest mass in the posterior neck
Action (unilateral contraction): Contralateral rotation of the neck
Action (bilateral contraction): Extension of the head/neck
Semispinalis
Deep muscle from S4-C2 (skipping 1-3 vertebrae)
Only muscle whose fibres run across the posterior sacrum
Actions (unilateral contraction): Lateral flexion, Contralateral rotation
Actions (bilateral contraction): Extension of the spine, stabilization
Multifidus
Deepest muscle in the Laminar groove
Attaches TVPs to SP above
Action (unilateral contraction): Contralateral rotation
Action (bilateral contraction): Stabilization
Rotatores
(Longus and Brevis)
Rotatores muscle that skips 1 vertebra
ex. TVP of C6 to SP of C4
Rotatores Longus
Rotatores muscle that attaches to the next highest vertebra
Ex. TVP of C6 to SP of C5
Rotatores Brevis
A paired muscle (on either side of cervical and lumbar SPs) of the deep layer of the Deep back muscles
Has a vertical fibre direction
Action: extension (small movement)
Interspinales
A muscle of the deep layer of the Deep back muscles
Attaches TVPs of adjacent vertebrae of the cervical and lumbar spine
Has a Verticle fibre direction
Action: lateral flexion (small movement)
Intertransversarii
