Cervical Spine Anatomy-Lecture

Question 1

Features of a typical cervical vertebrae

Answer 1

• small but wide oval body with uncinate process
• may have bifid spinous process (more common in caucasian)
• foramen transversarium in transverse process
• large triangular vertebral foramen
• artic process face A/P

Question 2

Motions of cervical vertebrae

Answer 2

• The Vertebrae are capable of performing all six motions in space
• Fryette’s law of cervical spine biomechanics – side bending and rotation occur to the same side.
  
  • C0-C1 (OA) – 10 to 15 degrees of flex/ext, 8 – lateral flex, minimal rotation
  • C1-C2 (AA)– 10 degrees flex/ext, 45 degrees of rotation, little lateral flexion
  • C3-C7 – 64 degrees of flexion, 24 degrees of extension, 40 degrees of lateral flexion, 40 degrees of rotation

Question 3

C1- Atlas

Answer 3

• A ring-like bone with no body, but 2 lateral masses. Note the angles of the articular surfaces
• An anterior and a posterior arch each with a tubercle
• Transverse processes with transverse foramina

Question 4

C2- Axis

Answer 4

• Most prominent feature is the odontoid process (dens) that is formed by tissue that would have been the body of C1
• Small body
• Very short spinous process

Question 5

C7- Vertebra prominens

Answer 5

• Resembles a thoracic vertebra with a long spinous process

Question 6

Joints of the vertebral column

Answer 6

• ATLANTO-OCCIPITAL
  
  • 2 synovial joints between the occipital bone of the skull and the atlas (C1)
• ATLANTO-AXIAL
  
  • 3 synovial joints between the atlas and the axis (C2)
• INTERVETEBRAL JOINTS
  
  • Symphysis joints between the bodies of adjacent vertebrae
  • Zygopophyseal joints –synovial joints between the superior and inferior articular processes of adjacent vertebrae

Question 7

Atlanto-occipital & Lateral Atlanto-axial Joints

Answer 7

• ATLANTO-OCCIPITAL:
  
  • BETWEEN THE SUPERIOR ARTICULAR FACETS AND THE OCCIPITAL CONDYLES
• LATERAL ATLANTO-AXIAL:
  
  • BETWEEN THE INFERIOR ARTICULAR FACET OF THE ATLAS AND THE SUPERIOR ARTICULAR FACET OF THE AXIS

Question 8

Central Atlanto-axial Joint

Answer 8

• BETWEEN THE ODONTOID PROCESS OF THE AXIS AND THE ANTERIOR ARCH OF THE ATLAS
• Alar ligament and Apical ligament –
  
  • secondary stabilizer C1-C2
• Tranverse ligament –
  
  • Retains odontoid process of C2 in place against anterior arch of atlas

Question 9

Ligaments of the
Atlanto-occipital & Atlanto-axial Joints

Answer 9

• Resists hyperflexion, posterior disk protrusion – Tectorial membrane (upper cervical)

Question 10

Intervertebral Disc- Annulus fibrosis

Answer 10

• outer layer of obliquely oriented layers of fibrous tissue connecting the compact bone of two adjacent vertebrae
• inner layer of fibrocartilage attaching to the articular surfaces of the adjacent vertebrae

Question 11

Intervertebral disc- NUCLEUS PULPOSUS

Answer 11

• a highly hydrated gelatinous connective tissue. In children it is formed by the remnants of the notochord, but in adults it is replaced by cartilaginous tissue.

Question 12

Fluid shifts in IV discs

Answer 12

• The intervertebral disk is a hydrostatic system that is resilient under pressure.
• The annulus fibrosis prevents fluid from escaping laterally, but its oblique fibers allow compression and expansion.
• The nucleus pulposus is 80-85% water. Under transient pressure it resists compression.
• When sustained pressure is applied to the disk (red arrows) the water is slowly forced out of the disk into the marrow cavities of the vertebral bodies.
• When the pressure is reduced, the water returns to the disk.
• During the day, the weight of the upper body causes a 1.5-2 cm loss of height due to water loss from the disks.

Question 13

Herniation of the Intervertebral Disk

Answer 13

• Weakness of the annulus fibrosis can lead to herniation of the nucleus pulposus.
• The most common sites are posteriorly, or posteriolaterally.
• A posterior herniation will press directly on the spinal cord, while a posteriolateral herniation will press on the root of a spinal nerve.

Question 14

ZYGOPOPHYSEAL JOINTS

Answer 14

• PLANE TYPE SYNOVIAL JOINTS BETWEEN THE SUPERIOR AND INFERIOR ARTICULAR PROCESSES OF ADJACENT VERTEBRAE

Question 15

ARTHRITIS OF THE VERTEBRAE

Answer 15

• Osteoarthritis can cause bony growths (osteophytes) to form on the vertebrae. These can limit motion and cause pressure on the spinal nerves as they travel through the intervertebral foramina.

Question 16

Ligamentum nuchae

Answer 16

• Attachment of the trapezius and splenius capitus
• extends from the external occipital protuberance on the skull and median nuchal line to the spinous process of the seventh cervical vertebra in the lower part of the neck

Question 17

Erector spinae- Spinalis

Answer 17

• ORIGIN & INSERTION ON SPINOUS PROCESSES
• SPINALIS CAPITIS – BLENDS WITH SEMISPINALIS CAPITIS
• SPINALIS CERVICIS – FREQUENTLY ABSENT
• SPINALIS THORACIS – THE LARGEST

Question 18

Erector spinae- Longissimus

Answer 18

• MIDDLE: LONGISSIMUS – ORIGIN & INSERTION ON TRANSVERSE PROCESSES
• LONGISSIMUS CAPITIS – C2-6 TO MASTOID PROCESS OF SKULL
• LONGISSIMUS CERVICIS – UPPER THORACIC TO C2-6
• LONGISSIMUS THORACIS – ILIOLUMBAR TENDON TO UPPER THORACIC

Question 19

Erector spinae- Iliocostalis

Answer 19

• LATERAL: ILIOCOSTALIS - ORIGIN & INSERTION AT THE ANGLE OF THE RIBS
• ILIOCOSTALIS CERVICIS – UPPER RIBS TO TRANSVERSE PROC. OF C5-7
• ILIOCOSTALIS THORACIS – LOWER RIBS TO UPPER RIBS
• ILIOCOSTALIS LUMBORUM – ILIAC CREST TO LOWER RIBS

Question 20

Semispinalis Capitis

Answer 20

• SEMISPINALIS CAPITIS
  
  • ORIGIN: T1-T6 TRANSVERSE PROC. & ARTICULAR PROC. OF C4-C7
  • INSERTION: SKULL BETWEEN SUPERIOR & INFERIOR NUCHAL LINES

Question 21

Semispinalis Cervicis

Answer 21

• SEMISPINALIS CERVICIS
  
  • ORIGIN: T1-T6 TRANSVERSE PROCESSES
  • INSERTION: SPINOUS PROCESSES OF C1-4

Question 22

Semispinalis Thoracis

Answer 22

• SEMISPINALIS THORACIS
  
  • ORIGIN: T7-T12 TRANSVERSE PROCESSES
  • INSERTION: SPINOUS PROCESSES OF LOWER C AND UPPER T

Question 23

Multifidus

Answer 23

• ORIGIN: POSTERIOR SACRUM, PSIS, FASCIA OF ERECTOR SPINAE, SACROILIAC LIGAMENTS, MAMMILLARY PROCESSES OF LUMBAR VERTEBRAE, TRANSVERSE PROCESSES OF T1-T3, ARTICULAR PROCESSES OF C4-C7
• INSERTION: ON SPINOUS PROCESSES OF VERTEBRAE 2 TO 4 SEGMENTS SUPERIOR TO THE ORIGIN
• THE FIBERS OF THIS MUSCLE ARE SHORTER THAN THE PRECEEDING ONES. IT IS ALSO DEEP TO BOTH ERECTOR SPINAE AND TO SEMISPINALIS. IT IS LARGEST IN THE LUMBAR REGION.

Question 24

Deep muscles: Deep layer (segmental muscles)

Answer 24

• Interspinales – Spinous Process
• Rotators - Transverse Process to Lamina and/or Spinous Process
• Levators – spans between transverse process