Session 2: Vertebral Column and Spinal Cord Flashcards
Which part is the lamina of the vertebra?
Between the spinous process and the transverse process
where is the pedicle of the vertebra?
Between the transverse process and the vertebral bod
What name is giving to the joints between the articular facets ofadjacent vertebrae?
zygapophyseal joints between the articular processes of two adjacent vertebrae
Describe some distinctive features of cervical vertebrae.
Triangular vertebral foramen
rectangular vertebral body
Transverse foramina in the transverse processes
Bifid spine (bifid=divides into 2 parts, see pics) (except C1 and C7)
Atlas and axis (C1 and C2) are specialized for movement see slide 11
Describe some distinctive features of thoracic vertebrae.
Bigger than cervical vertebrae
Circular vertebral foramen
Heart shaped vertebral body
Spinous process pointing sharply downwards
Transverse costal facets (for rib articulation) see slide 11
Describe some distinctive features of lumbar vertebrae.
LARGE Articular facets are angled to limit movement
Thin, long transverse processes (except L5)
Triangular vertebral foramen
kidney shaped vertebral body see slide 11
How many bones fuse to form the sacrum?
5
Describe the structure of the sacrum.
Concave anterior surface Triangular in shape L shaped articular facets (for articulation with pelvic bones)
How many bones fuse to form the coccyx?
3-4
Vertebral arches (this is everything except the vertebral body, search up pic) and canal are absent
What two types of joint are found between vertebrae?
Symphysis – between adjacent vertebral bodies Synovial Joints – between articular processes
How many joints are there between two typical vertebrae?
6 2 symphyses (above and below) 4 synovial joints (2 superior and 2 inferior)
Between which vertebrae do you find intervertebral discs?
C2-S1 There is no intervertebral disc between C1 and C2, if there was then your head won’t be able to move a lot because atlas and axis joints are important in head movement
What are the two parts of the intervertebral disc?
Nucleus pulposus Annulus fibrosus
Describe how problems with the intervertebral disc can lead to potential clinical problems.
Degenerative changes in the annulus fibrosus can lead to herniation of the nucleus pulposus, which can then impinge on spinal nerves or thespinal cord
Name the two ligaments that rung along the length of the vertebral bodies from the skull to the sacrum.
Anterior and Posterior Longitudinal Ligaments
Which ligament is typically damaged in whiplash (sudden head movement, typically in a car accident)?
Anterior Longitudinal Ligament see diagram on slide 29
What is the name given to the upper part of the posterior longitudinal ligament going from C2 to the skull?
Tectorial Membrane- thin superior continuation of the posterior longitudinal ligament from the axis to the foramen magnum
Which ligament is pierced in lumbar puncture and where is it positioned relative to the vertebral bodies?
Ligamentum flavum – found between the laminae of adjacent vertebrae
Name the triangular sheet-like structure found in the upper vertebral column. Where is it attached?
Ligamentum nuchae – attached from C7 to the occipital bone
What it continuous with the ligamentum nuchae and which part of the vertebrae is this attached to?
Supraspinous ligament It connects to the spinous processes from C7 to the sacrum
Which ligament lies between adjacent spinous processes?
Interspinous ligament
State the origin, insertion and function of: a. Serratus Posterior Superior b. Serratus Posterior Inferior
a. Serratus Posterior Superior
Origin –C7-T3
Insertion – upper border of ribs 2-5
Function – elevates ribs 2-5
b. Serratus Posterior Inferior
Origin – T11-L3
Insertion – lateral inferior margins of ribs 9-12
Function – depresses ribs 9-12 and prevents lower limbs from elevating when the diaphragm contracts
Describe the flexibility of the cervical spine in terms of flexion/extension, lateral flexion and rotation.
Cervical spine can comfortably flex, extend, laterally flex and rotate. The articular surfaces between vertebrae are almost horizontal, so all these movement are possible. Also the neck has less surrounding tissue than other parts of the spine
Describe the flexibility of the upper thoracic spine (T1-T6).
NO flexion/extension Some lateral flexion Some rotation The articular surfaces are almost vertical, which doesn’t allow for flexion/extension.
Describe the flexibility of the lower thoracic spine (T7-T12).
Some flexion/extension Good lateral flexion Good rotation
Describe the flexibility of the lumbar spine (L1-sacrum).
NO rotation Good flexion/extension Good lateral flexion Their articular surfaces are curled around the articular surfaces of the adjacent superior vertebrae, ensuring no rotation.
Describe the shape of the atlas (C1).
ATYPICAL VERTEBRA It has NO vertebral body It consists of two lateral masses with an anterior and posterior arch. These arches form the ring which is the vertebral foramen containing the spinal cord
Describe the articulations of the atlas.
The two lateral masses articulate superiorly with the occipital condyles (these are the bulges on the occipital bone that bind to the two ‘pillars’ of the atlas) and inferiorly with the superior articular surfaces of C2 (axis)
Describe the structure of the axis (C2).
It is an atypical cervical vertebra The axis (C2) is unique with an ODONTOID PROCESS (the dens) projecting from its superior surface. The dens has a posterior articular facet that binds to the C1 atlas and the dens allows the c1 to rotate clockwise and anticlockwise around the dens. (Part of the Atlantoaxial joint aka the NO joint) https://www.youtube.com/watch?v=b5NjhaG2SbY&frags=pl%2Cwn
Which ligaments are attached to the dens? (odontoid process of the axis c2 vertebra)
- The transverse ligament of the atlas keeps the dens in place, against the articular surface on the posterior side of the ANTERIOR arch of the atlas.
- Alar ligaments are attached to the superiolateral surfaces of the dens and the medial occipital condyles. The alar ligaments prevent excessive rotation of the head.
NB transverse ligament is part of the cruciate ligament (see pic below)
google alar ligaments
State 5 important vertebral landmarks and how you would identify them on an individual. C7 T3 t7 L2 L4
C7 – vertebra prominens
T3 – level of the medial end of the scapular spine and jugular notch
T7 – level of the inferior angle of the scapula
L2 – level of the lowest rib
L4 – level with the iliac crest
How many sacral vertebrae are there?
5 (fused)
How many coccygeal vertebrae are there?
1-4 (fused)
How many vertebrae are there in total?
30-33 depending on how many coccygeal vertebrae there are
Which layer of cranial dura mater is the spinal dura mater continuous with?
Meningeal layer of the cranial dura
At what level does the dural sac narrow around the filum terminale? (the tip of the spinal cord is called the conus medullaris, Below this is the cauda equina. The filum terminale is a filament/string extension of the Pia mater that extends inferiorly from the conus medullaris down to the bottom of the spine)
S2
What space is present in the vertebral column that you don’t find in the skull?
Epidural space
What does this space contain?
Connective tissue
Fat
Internal vertebral venous plexus
What is the arachnoid membrane and where does it end?
It is a thin, delicate membrane that is against but not adherent to the deep surface of the dura mater. It ends at S2
What thin structures interconnect the arachnoid and pia mater?
Arachnoid trabeculae – these are the individual ‘cobwebs’ in the subarachnoid space and they also suspend vessels in the subarachnoid space
Where does the subarachnoid space end?
S2
What is the spinal pia mater?
A vascular membrane that firmly adheres to the surface of the spinal cord
What are the longitudinally oriented sheets of pia mater that youfind on either side of the spinal cord?
Denticulate ligaments, these attach to the dura mater and help to suspend the spinal cord
Where do these ligaments attach medially and laterally?
Medially – to the spinal cord Laterally – form a series of triangular extensions that anchor through the arachnoid membrane to the dura mater function- helps to suspend the spinal cord
Why would you perform a lumbar puncture?
To obtain some CSF (e.g. to test for meningitis) To inject spinal anaesthesia (into the epidural space)
At which level would you perform a lumbar puncture?
L3/L4 in an adult 1 or 2 vertebral spaces lower in a child
Which ligament is pierced in lumbar puncture?
Ligamentum flavum
Why would you never do a lumbar puncture in the case of raised intracranial pressure?
It will cause a sudden relieving of pressure, which could cause brainstem herniation and death.
State some signs of cervical spine injury.
Low blood pressure + high pulse Large erection (Custer’s last stand) Flaccid paralysis Large bladder and inability to micturate
What steps would you take in the on scene management of a potential C-spine injury?
Assume unstable fracture Assume neck pain if unable to communicate neck pain Use cervical collar and blocks to immobilize the neck
What steps would you take in the hospital management of a potential C-spine injury?
Take lateral and AP X ray, C-spine – if fracture, image with CT/MRI Give steroids – could prevent the death of around 1 cm of spinal cord Treat any other symptoms e.g. low BP
Why is lower back pain the most common form of back pain?
Low spine is subject to increased stresses of weight bearing so the lumbar region is most commonly affected. We tend to abuse our backs, particularly when lifting heavy objects. Extending the spine from the fully flexed position under a heavy load can inflame intervertebral joints or place unequal pressureon the intervertebral disks, leading to local joint pain and referred neurological pain, if there is also pressure on the spinal nerve Additional attempts to rotate the spine at the same time creates extra stress on the lumbar joints.
State 3 common deviations in spinal curvature.
Scoliosis = abnormal lateral curvature of the spine
Kyphosis = excessive outward curvature of the spine, causing hunching of the back
Lordosis = excessive inward curvature of the spine
What is sciatica
condition of leg pain/numbness etc due to PROLAPSED DISC pressing on sciatic nerve which supplies the legs
Spondolysis Spondylolysis Spondylolisthesis Spondylitis
Spondolysis (degeneration of intervertebral disc)
Spondylolysis (stress fracture of pars interarticularis)
Spondylolisthesis (forward slipping/displacement of vertebra)
Spondylitis (inflammation of vertebrae)
Superficial back muscle examples
Superficial: Trapezius Latissimus dorsi Levator scapulae Rhomboid minor Rhomboid major
Intermediate back muscle examples
Intermediate: Serratus posterior superior Serratus posterior inferior
Deep back muscles examples
Deep Spinotransversales Erector spinae Transversospinales Interspinales Intertransversarii
State the origin, insertion and function of A a. Trapezius b. Latissimus Dorsi c. Levator Scapulae d. Rhomboid Minor e. Rhomboid Major
a. Trapezius Origin – external occipital protuberance, cervical and thoracic spine Insertion – clavicle and scapula Function – elevate and rotate the scapula when the humerus is abducted
State the origin, insertion and function of B a. Trapezius b. Latissimus Dorsi c. Levator Scapulae d. Rhomboid Minor e. Rhomboid Major
b. Latissimus Dorsi Origin – T7 to sacrum + thoracolumbar fasica + posterior 1/3 of iliac crest Insertion – intertubercular sulcus of the humerus Function – extends, adducts and medially rotates the humerus
State the origin, insertion and function of C a. Trapezius b. Latissimus Dorsi c. Levator Scapulae d. Rhomboid Minor e. Rhomboid Major
c. Levator Scapulae Origin – transverse processes of C1-C4 Insertion – upper medial scapula Function – elevates the scapula
State the origin, insertion and function of D a. Trapezius b. Latissimus Dorsi c. Levator Scapulae d. Rhomboid Minor e. Rhomboid Major
d. Rhomboid Minor Origin – spinous processes of C7-T1 Insertion – medial border of scapula Function – adduct and elevate scapula
State the origin, insertion and function of E a. Trapezius b. Latissimus Dorsi c. Levator Scapulae d. Rhomboid Minor e. Rhomboid Major
e. Rhomboid Major Origin – spinous processes of T2-T5 Insertion – medial border of scapula Function – adduct and elevate scapula
State the location and function of A a. Spinotransversales b. Erector Spinae and Transversospinales c. Interspinales and Intertransversarii
a. Spinotransversales Extensors and rotators of the head and neck The two spinotransversales muscles run from the spinous processes up to T6 and ligamentum nuchae, running superiorly and laterally
State the location and function of B a. Spinotransversales b. Erector Spinae and Transversospinales c. Interspinales and Intertransversarii
b. Erector Spinae and Transversospinales Extensors and rotators of the vertebral column Erector spinae lie posterolaterally to the vertebral column between the spinous processes medially and the angles of the ribs laterally Transversospinales run obliquely upward and medially from the transverse process to the spinous process
State the location and function of C a. Spinotransversales b. Erector Spinae and Transversospinales c. Interspinales and Intertransversarii
c. Interspinales and Intertransversarii These are short segmental muscles that are the stabilisers of the vertebral column Interspinales – pass between adjacent spinous processes Intertransversarii – pass between adjacent transverse processes
Blood supply of the spinal cord?
mainly from:
- Spinal arteries that arise from vertebral arteries
(1 anterior spinal a. , 2 posterior spinal a.)
- Reinforced by radicular arteries that arise from various sources including the posterior intercostal arteries and lumbar arteries (these are parallel with intercostal a. but in lumbar region)
Note that in the picture, these vessels are below the arachnoid matter in the subarachnoid space
filum terminale is continuation of
pia mater, it originates from the conus medullaris (the tapered end of the spinal cord hence called a cone)
Clincial significance of the venous plexues surrounding the spinal cord?
can allow spread of prostate cancer to the brain
