Deep Back Muscles Flashcards
Extrinsic muscles of the back that produce and control limb movements
Superficial muscles of the back
Extrinsic muscles of the back involved in producing respiratory movement
Intermediate muscles
The intrinsic muscles of the back, muscles that specifically act on the vertebral column, producing its movements and maintaining posture
Deep muscles
Describe the terms extrinsic vs. intrinsic in terms of the muscles of the back
Extrinsic don’t belong to back itself, they originate from outside the back and act on the back
Intrinsic muscles are belonging to or originating in the back itself specifically acting on the vertebral column to produce movements and maintain posture
The two purposes of the superficial (extrinsic) back muscles
Connect upper limb to the trunk
Control limb movement
The superficial (extrinsic) back muscles are innervated by nerves formed from
Ventral rami
Name the superficial back muscles
Trapezius
Latissimus dorsi
Levator scapulae
Rhomboids
Intermediate (extrinsic) back muscle that lies deep to the rhomboids extends from spines of vertebral column to ribs 2-5
Serratus Posterior Superior
Intermediate (extrinsic) back muscle that lies deep to the latissimus dorsi extends upward from lower thoracic and upper lumbar spines to ribs 9-12
Serratus posterior inferior
Origin and insertion of serratus posterior superior
Origin: Spines of vertebral column to
Insertion: ribs 2-5
Origin and insertion of serratus posterior inferior
Origin: Lower thoracic and upper lumbar spines
Insertion: Ribs 9-12
These two muscles can hypertrophy when respiration is difficult and may have function in respiratory movement
Serratus Posterior Superior and Serratus Posterior Inferior
Innervation of the serratus posterior inferior and serratus posterior superior
Intercostal nerves from ventral rami of spinal nerves
Group of muscles of the back that maintain posture and control movement of the vertebral column, they extend from the skull to the pelvis
Deep (intrinsic) muscles of the back
The three groups of the deep back muscles
Superficial intrinsic layer
Intermediate intrinsic layer
Deep Instrinsic Layer
All of the deep muscles of the back are innervated by…
dorsal rami of spinal nerves
Innervates all of the other muscles in the body wall and in the extremity, and is therefore much larger
Ventral rami of spinal nerves
Layer consisting of splenius capitis and cervicis
Superficial Intrinsic Layer
What are the actions of the splenius capitis and the splenius cervicis?
Extend the head and neck if contracted bilaterally
Pull the head and neck to the same side unilaterally
Origin of the splenius cervicis
Origin: Ligamentum Nucae and spinous process C7-T6
Insertion: Transverse processes of C1-C4
Origin of the splenius capitis
Ligamentum Nucae and spinous process C7-T6
Insertion: Mastoid process (upper portion) and partially occipital bone
Group of muscles of the back called the erector spinae that extends from the pelvis to the skull and fills the space in between the spinous processes and the angle of the ribs
Intermediate Intrinsic Layer
Extend from sacrum of iliac crest all the way to the back of the head
Erector Spinae
3 divisions of the erector spinae arranged longitudinally running parallel to one another (lateral to medial) (I love spaghetti!)
Iliocostalis
Longissimus
Spinalis
Important action of the erector spinae
Maintaining posture
When muscles on both side contract, what occurs?
What about when one side contracts?
Straighten back and pull head posteriorly
Flex vertebral column so body turns to same side and turn chin to same side
Most lateral part of the erector spinae column
Iliocostalis
Origins of the iliocostalis (lumborum, thoracic, and cervicis portion)
Insertion of iliocostalis
Origins: Iliac crest
Inferior six ribs
Ribs 3-6
Insertion: Angle of the ribs (lumborum and thoracis)
Transverse processes of C6-C4 for cervical portion (cervicis)
Innervation of the iliocostalis
Dorsal spinal nerves
Action of the iliocostalis
Extend vertebral column or bend to one side if acting ipsilaterally (lateral flexion)
What is the intermediate column of the erector spinae (largest?
Longissimus
Origin and insertion of the longissimus
Origin: Transverse processes of lumbrical and cervical vertebrae
Insertion:Transverse processes of thoracic and cervical vertebrae, mastoid process
Innervation of longissimus
Dorsal rami of spinal nerves
Thoracis and cervicis portions acting together have what action?’
What about acting individually?
Extend vertebral
Bend it laterally to that side (lateral flexion)
Action of the capitis when working together
When working individually
Extend the head
Turn face to the same side (ipsillaterally)
Most medial columnof the erector spinae
Spinalis
What is the action of the spinalis?
Extends vertebral column and head
Origin and insertion of the spinalis
Spinous process of lumbar and lower thoracic
Spinous process of upper thoracic and cervical vertebrae
Innervation of the spinalis
Dorsal Rami of spinal nerves
Action of the spinalis
Extend vertebral column and possibly head
The term for where the origin of many muscles of erector spinae group is
thoracolumbar/thoracodorsal fascia
Deepest group of the deep muscles of the back
Transversospinal Group
name the 3 type of muscles in the transversospinal group
Semispinalis
Multifidus
Rotatores
Muscles that extend from transverse process to a spinous process and cross approximately 6 vertebrae
Semispinalis
Muscles that extend in same direction as semispinalis but only cross 4 vertebrae
Multifidus
Extend from transverse proccess and cross one or two vertebrae to extend to spinous process or lamina immediately above
Rotatores
Origin and insertion of the semispinalis
Origin: Cervical and thoracic transverse processes
Insertion: Occipital Bone
Origin and insertion of the semispinalis in the thoracic and cervical regions
Origin: Tranverse processes
Insertion: Spinous processes 6 vertebrae higher
Where does the semispinalis capitis portion ascend to?
The head
Origin and insertion of the multifidus
Origin: Transverse Processes
Insertion: Spinous processes
Actions of the multifidus when acting together and alone
Together: Extend vertebral column
Alone: Rotate body to opposite side
Origin and insertion of rotatores
Origin: Tranverse process
Insertion: Vertebrae above or one higher
Action of all the transversospinal when acting alone and together
Extend vertebral column
Rotate body to opposite side
Not a real back muscle that is located on the posterior abdominal wall.
Fills in the space from the 12th rib and iliac crest
Quadratus Lumborum
Origin and insertion of quadratus lumborum
Origin: Iliac Crest
Inserts: Transverse processes of upper lumbars and margin of 12th rib
Innervation of the quadratus lumborum
Ventral Rami, from T12 and L1-4
Action of quadratum lumborum acting together and alone
Extend vertebral column
Bend body to that side
Forceful respiration by holding 12th rib in space and expanding thoracic cavity
In sum, which of the three layers in the back connect and move the upper limb?
Superficial
Which layer aids in respiration?
Intermediate
Which moves the vertebral column and maintains posture?
Deep