Lecture Notes - Deep Back & Spinal Cord

The streaming video of the 2004-5 lab overview is available on the web (password protected).
The computer presentation used by Dr. Burkel in lecture is available on the web (password protected). You can also download the PowerPoint presentation to print or review.

  1. The Back
    1. Superficial back muscles: really limb muscles - anterior rami of spinal nerves
    2. True or Deep back muscles (Paraspinal muscles - posterior rami of spinal nerves)
      1. Erector spinae - main bulk of back muscles - from sacrum to skull
      2. Transversospinal group - multifidus, etc.the shortest and the deepest layers
      3. Others: splenius, suboccipital muscles, interspinales, rotators, etc.
      4. Function - to keep the spine erect, bend it laterally, and rotate it.
  2. Vertebral Column
    1. Vertebrae
      1. 33: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused), 4 coccygeal (fused)
      2. Parts:
        1. body - weight bearing part;
        2. vertebral arch - muscle attachment, etc.
        3. vertebral, spinal foramen - between body and vertebral arch, contains spinal cord
        4. vertebral notches - adjacent notches form intervertebral foramen to transmit spinal nerve
      3. Regional variations - vertebrae each region are different, some special
    2. Joints - join vertebrae
      1. Intervertebral Disks (cartilagenous joints)
      2. Facet joints (synovial joints - zygopophyseal joints)
    3. Ligaments - join vertebrae, longitudinal (ant., post), ligamenta flava, supraspinal
    4. Curvatures - Thoracic and sacral - primary ; cervical and lumbar - secondary
    5. Blood Supply - segmental and vertebral vessels - see spinal cord vessels
    6. Nerve Supply - to meninges, vertebrae, disks, ligaments and joints
    7. Abnormalities or defects, etc.
      1. fused or missing vertebrae
      2. scoliosis, lordosis, kyphosis, herniated disks
  3. Gross Spinal Cord and Meninges
    1. Spinal Cord - CNS from medulla oblongata of brain to tip of conus medullaris (L2),
      1. Same regions as vertebral column - cervical, thoracic, lumbar, sacral, coccygeal
      2. Segment - section of spinal cord giving rise to a specific spinal nerve; 31 segments
      3. Enlargements - cervical and lumbosacral - cord larger where nerves to limbs arise
      4. Conus medullaris - terminal tapered end of cord, tip of which is at L2
      5. Cauda equina - free floating spinal nerve rootlets (lower L2 - S2) in CSF
      6. Spinal nerve rootlets - not really parts of spinal cord, but of spinal nerves
    2. Meninges and Spaces - contents of vertebral canal from outside in:
      1. Epidural space - contains fat and vertebral plexus of veins
      2. Dura mater - outer covering - "durable" dural sac ends at S2
      3. Subdural space - a potential space between dura and arachnoid
      4. Arachnoid mater - looks like a "spider web" attached to pia by trabeculae
      5. Subarachnoid space - between arachnoid and pia ends at S2, contains cerebrospinal fluid (CSF) to bathe and cushion the brain and spinal cord,
      6. Pia mater - outer layer of CNS, forms dentate ligaments and filum terminale
    3. Blood Supply of Vertebrae and Spinal Cord
      1. Arterial - segmental arteries from which arise: branch to the vertebra, radicular which join to form anterior spinal and posterior spinal arteries.
      2. Venous - vertebral venous plexus - connects to segmental veins inf. vena cava.
    4. Functional Considerations
      1. Lumbar puncture (Spinal tap) - to remove CSF for analysis
      2. Anesthesia - spinal; epidural (extradural); caudal
      3. Herniated disks - radiculopathies
      4. Developmental defects - spina bifida, meningocele, myelomeningocele