Intrinsic Back Muscles - Dorsal Rami Spinal Nerves Flashcards
Superficial Layer: Splenius mm. (2)
- Splenius Capitis
Origin: Cerevical spinous processes and nuchal ligament
Insertion: Mastoid process of temporal bone, superior nuchal line
Innervation: Dorsal rami spinal nerves
Function:
1. Capital extension
2. Rotation of head to same side
3. Lateral bending of head to same side
- Splenius Cervicis
Origin: Spinous processes
Insertion: Transverse processes, posterior tubercles
Innervation: Dorsal rami spinal nerves
Function:
1. Extension and Rotation of cervical spine to same side
2. Lateral bending to same side
Intermediate layer: Erector spinae mm. - Iliocostalis (3)
- Iliocostalis Lumborum
Origin: Common tendon of erector spinae, thoracolumbar fascia, Iliac crest, sacrum
Insertion: Transverse process, Ribs 5/6-12
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of spine
2. Lateral bending of spine on the same side
3. Depression of ribs
4. Elevation of pelvis
- Iliocostalis Thoracis
Origin: Ribs 12-7
Insertion: Ribs 1-6, C7 transverse process
Innervation: Dorsal rami spinal nerves
Function:
1. Extension and Lateral bending of spine on the same side
2. Elevation of pelvis
- Iliocostalis Cervicis
Origin: Ribs 3-6
Insertion: Transverse processes, posterior tubercles
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of cervical spine
2. Lateral bending to same side
3. Depression of ribs
Erector spinae mm. - Longissimus (3)
- Longissimus Thoracis
Origin: Common origin
Insertion: Transverse processes, Ribs 2-12
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of spine
2. Lateral bending to same side (unilateral muscle)
3. Depression of ribs
- Longissimus Cervicis
Origin: Transverse processes
Insertion: Posterior tubercles of transverse processes
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of cervical spine
2. Lateral bending of cervical spine to same side
Longissimus Capitis
3. (below Splenius Cervicis)
Origin: transverse processes T1-T4, C4-C7
Insertion: Mastoid process of temporal bone
Innervation: Dorsal rami spinal nerves
Function:
1. Capital extension
2. Lateral bending and rotation of head to same side
Erector spinae mm. - Spinalis (3)
1. Spinalis Thoracis
Origin: T11-L2 Spinous processes
Insertion: T1-L4 spinous processes
Innervation: Dorsal rami spinal nerves
Function: Extension of spine
- Spinal Cervicis
(below splenius capitis)
Origin: Spinous processes, nuchal ligament
Insertion: Axis, spinous processes
Innervation: Dorsal rami spinal nerves
Function: Extension of cervical spine
- Spinal Capitis
Origin: Spinous processes
Insertion: Occiput
Function: Capital extension
Innervation: Dorsal rami spinal nerves
Deep layer: Transversospinalis mm. - Semispinalis (3)
- Semispinalis Thoracis
Origin: (from) Thoracic transverse processes
Insertion: (to) Cervical spinous processes
Innervation: Dorsal rami spinal nerves
Function: Extension of thoracic spine
- Semispinalis Cervicis
Origin: Thoracic transverse processes
Insertion: Cervical spinous processes
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of cervical spine
2. Rotation of c-spine to opposite side
3. Lateral bending to same side
- Semispinalis Capitis
Origin: Transverse processes, cervical articular processes
Insertion: Occiput
Innervation: Dorsal rami spinal nerves
Function:
1. Capital extension
2.
Rotation of head to opposite side
3. Lateral bending of head to same side
Multifidus (1)
Origin:
1. Sacrum
2. Aponeurosis of Erector spinae
3. Posterior superior iliac spine
4. Sacroiliac ligaments
5. Lumbar mamillary processes
5. Thoracic transverse processes
5. Cervical articular processes
Insertion: Higher spinous processes
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of spine
2. Lateral bending of spine (unilateral muscle)
3. Rotation to opposite side
Rotatores (2)
Rotatores brevis and longus
Origin: Transverse processes
Insertion: Superior (higher level) spinous process
Brevis (short): SP of next vertebrae above
Longus: SP of 2nd vertebrae above
Innervation: Dorsal rami spinal nerves
Function:
1. Extension of spine
2. Rotation of spine to opposite side
Small muscles of deep back:
1. Interspinalis (3)
Innervation: Dorsal rami spinal nerves
Function:
Connect spinous processes
Extension and rotation of vertebral column
- Intertransversarii
Innervation: Dorsal rami spinal nerves
Function:
Connect transverse processes
Lateral flexion of vertebral column
Stabilize vertebral column
Levatores Costarum (2)
Breves and Longus
Insertion: transverse processes to rib tubercles
Innervation: Dorsal rami spinal nerves
Function:
1. Elevates ribs (costa ribs)
2. Assist with lateral flexion and respiration
