Back Muscles O/I/A

• splenius capitus insertion

  Nuchal line of occipital bone and mastoid process of

  temporal bone
• splenius cervicis insertion

  C1-C4 transverse processes
• splenius innervation

  Innervation - dorsal rami of spinal nerves C1-C6
• splenius blood supply

  Occipital artery and deep cervical artery
• innervation of the erector spinae muscles

  dorsal rami of spinal nerves (cervical, thoracic, lumbar spine)
• erector spinae blood supply

  occipital and deep cervical artery
• spinalis cervicis and thoracis insertion

  O:Spinous processes of C5-T2

  I:Spinous processes of cervical spine (cervicis)

  and thoracic vertebrae (thoracis) C2-T8
• longissimus attachments

  O: Sacrum, Iliac crest, Spinous processes of lumbar vertebrae, and transverse processes of C4-T12

  I: Mastoid process (capitis),

  transverse processes of cervical vertebrae (C2-C5; cervicis), transverse processes of thoracic and lumbar vertebrae with small rib attachments to ribs 2-12 (thoracis)
• Iliocostalis attachments

  O: Iliac crest, sacrum and ribs 3-12

  I: Transverse processes of cervical vertebrae C4-C6 (cervicis),

  Ribs 1-6 (thoracis),

  Ribs 6-12 and transverse processes of upper lumbar vertebrae (lumborum)
• erector spinae actions

  Bilateral - extends the vertebral column

  Unilateral - Lateral flexion ipsilateral side

  Contributes to rotation of the vertebral column
• rotatores (longi & brevis) attachments

  O: T1-T12 transverse processes

  I: C7-T11 thoracic region, spinous processes, adjacent attachment

  (breves) and skip one vertebrae (longi)
• multifidus attachments

  O: Transverse processes of C4-T4, mamillary processes of L1-L5, sacrum, and ilium

  I: Spinous processes (skips 2-4 vertebrae and runs from sacrum to C1, fibers run in a superomedial direction)
• semispinalis attachments

  O: Transverse processes C4 - T7 (capitis),

  T1-T6 (cervicis),

  T6-T12 (thoracis)

  I:Between superior and inferior lines of occipital bone (capitis)

  C2 - C5 cervical spinous processes (cervicis)

  C6-T4 thoracic spinous processes (thoracis)
• Splenius cervicis and capitis attachments

  O: Spinous processes of C7-T6 and nuchal ligament

  I: Transverse processes of cervical vertebrae (C1-C3; cervicis),

  superior nuchal line and mastoid process of skull (capitis)
• rectus capitis posterior minor attachments

  O: C1 (posterior tubercle)I: Inferior nuchal line
• rectus capitis posterior major attachments

  O: C2 (spinous process)I: Inferior nuchal line (lateral to minor)
• obliquus capitis inferior

  O: C2 (spinous process)I: C1 (transverse process)
• obliquus capitis superior

  O: C1 (transverse process)I: Inferior nuchal line (superior to rectus capitis posterior major)
• innervation of the suboccipital muscles

  suboccipital nerve
• blood supply to the suboccipital muscles

  vertebral and occipital artery