Back and Spine Flashcards
Explain what the spinal column consists of
7 cervical vertebrae
12 thoracic vertebrae
5 lumbar vertebrae
5 sacral vertebrae
3-5 coccygeal vertebrae
What are the most anterior and posterior structures of the vertebrae?
Anterior - body
Posterior - spinous process
What lies within the vertebral foramen?
Spinal cord
What lies within the intervertebral foramen?
Spinal nerves
What type of joint occurs between the bodies if the adjacent vertebrae?
Symphyses - secondary cartilaginous joint
Called intervertebral discs
What joints occur between the articular facets of the adjacent vertebrae?
Synovial plane
What is the name of the C1 and C2 vertebrae?
C1 - atlas
C2 - axis
What is the specific name of the C7 vertebrae?
Vertebrae prominens - largest and most inferior vertebrae in the neck
What are 2 features of the cervical vertebrae?
Smallest body
Spinous process branches into two
Also has 2 holes - transverse foramen
What are 2 features of the thoracic vertebrae?
Body is bigger than cervical but smaller than lumbar - heart shaped
Spinous points more downward
Presence of facets for the joints with the ribs
What are at least 2 features of lumbar vertebrae?
Transverse process are more lateral than thoracic
More prominent superior and inferior process - much larger
Has biggest vertebrae body
Absence of the foramen transversarium within the transverse process, and by the absence of facets on the sides of the body
What are Zygapophyseal (facet) joints?
They are plane synovial joints between the superior and inferior articular processes on adjoining vertebrae
Zygapophyseal joints extend between the axis (C2) and the first sacral vertebra (S1)
What are the parts of intervertebral discs?
Annulus fibrosis
Nucleus pulpous
Explain the condition ‘slipped disc’
Nucleus pulposus may protrude (herniate) through the annulus fibrosis. If serious protrusion then disc material can impinge on an emerging spinal nerve
In what direction does the nucleus pulposus have to protrude to compress spinal nerve and why does it herniate in this direction?
Posterolateral direction
This is where the annulus fibrosis is relatively thin and does not receive support from posterior or anterior longitudinal ligaments
What does the ligamentum flavum connect?
Laminae of the adjacent vertebrae
What does the anterior longitudinal ligament connect?
Body of the vertebrae and intervertebral discs
Theses are wide and strong
What does the posterior longitudinal ligament connect?
Body of vertebrae and prevents hyperextension
What does the supraspinous ligament connect?
Spinous processes
Only extends from C7
What does the interspinous ligament connect?
Inferior and superior parts of the spinous process
Name the ligaments of the spine on diagram?
Explain the curvatures of the vertebral column
Cervical curvature - concave posteriorly
Thoracic curvature - convex posteriorly
Lumbar curvature - concave posteriorly
Sacrococcygeal curvature - convex posteriorly
What curvatures are secondary curvatures in adults?
Cervical and lumbar curvature
What developmental changes occur in neonate to produce the secondary spinal curvatures?
Cervical - becomes prominent when infant holds its head up
Lumbar - when infant starts to walk and assume upright position
What are some exaggerated/ anomalous curvatures of the vertebral column?
Lordosis - lumbar exaggeration
Kyphosis - thoracic exaggeration
Scoliosis
What are the movements permitted in the cervical region?
Flexion is greatest in this region
Lateral flexion also is the greatest here
Rotation is also permitted
Extension
What are the movements permitted in the thoracic region?
Rotation is permitted
Flexion is limited, including lateral flexion
What are the movements are permitted in the lumbar region?
Flexion and extension is permitted
Extension is most in this region and is more marked than flexion
Rotation is prevented
What plane are the cervical articular facets of each vertebrae orientated?
Horizontal/ transverse plane
What plane are the thoracic articular facets of each vertebrae orientated?
Coronal plane
What plane are the lumbar articular facets of each vertebrae orientated?
Sagittal plane
Describe the erector spinae muscles
Main muscles of the vertebral column
Lie posteriorly between vertebrae transverse and spinous processes
What are the anteriorly situated muscles that act on vertebrae column?
Sternocleidomastoid in the neck and the anterior abdominal wall muscles - obliques, rectus abdominis and transverse abdominis
What vertebral level is the vertebral prominence?
Spinous process of C7
What vertebral level is the spine of scapula?
Spine of T3
What is the vertebral level of the inferior angle of scapula?
Spine of T7
What is the vertebral level of the summit of iliac crest?
Spine of L4
Where is a lumbar puncture performed in an adult and child?
Adult - between L3 and L4
Child - between L4 and L5
Why is the patient, who is getting a lumbar puncture, requested to flex their lumbar spine?
Spreads the laminae and spinous process apart which stretched the ligament flava
What causes the intervertebral disc to prolapse or herniate?
Ageing, heavy lifting or exercising too hard
Occurs posterolateral
Where are the enlargements of the spinal cord and why are they enlarged?
Cervical and lumbar enlargements
Result from enlargement of its grey matter necessary to supply the limbs
Explain where the spinal cord extends from
Extends from the occipital bone of the skull and extends down to the intervertebral disc between the first and second lumbar vertebrae
What does the spinal cord form at the distal end?
Conus medullaris
Terminates at the fibrous extension known as the filum terminale
At what vertebral level does the spinal cord terminate in an adult and in a child?
Adult - L1-L2
Child - L3
Which spinal nerves form the cauda equina and what spinal cord do they emerge?
L2-S5
Emerge from the conus medullaris
Where does the filum terminale attach inferiorly and what is its function?
Dural sac
Serves as an anchor for the inferior ends of the spinal cord
Explain the degree of spinal cord injuries at different vertebral levels?
Cervical - canal is relatively large so spinal cord escapes severe injury unless considerable vertebral or cord displacement occurs
Thoracic - canal is small and displacement is often considerable causing severe injury
Lumbar - spinal cord only extends to L1/L2 and canal is quite large so nerve injury is minimal
What makes up the grey matter of the spinal cord?
Nerve cell bodies
What makes up the white matter of the spinal cord?
Nerve fibres - many surrounded by myelin
What type of nerve impulses are associated with the anterior horn cells?
Motor
What type of nerve impulses are associated with the posterior horn cells?
Sensory
What type of nerve cells are associated with the lateral horn cells?
Automatic
What are the 3 layers of meninges?
Dura mater
Arachnoid mater
Pia mater
What is the primary function of the meninges?
Protect and cushion the central nervous system
Where does the Dural sac terminate in an adult and in a newborn?
Adult - S2
Newborns - S3
What is between the arachnoid and pia mater?
The subarachnoid space
Contains Cerebrospinal fluid
What is the space between the dura mater and the vertebrae bones?
Epidural space or extradural space
What is damage/ inflammation to the meninges cause?
Meningitis - inflammation
Can cause severe neurological damage and even death
Describe arterial blood supply to the spinal cord
Is via spinal arteries arising from aorta and its branches
What plexus drains the vertebrae and the spinal cord?
Vertebrae venous plexus
Where is the vertebrae venous plexus found?
In fatty tissue between dura mater and the vertebrae - epidural space
Why do the vertebral venous plexus have no valves?
Because of communication between the body wall and the CNS the plexus of veins provides a possible route of communication for metastasis of cancer cells
What type of nerves are spinal nerves?
Mixed nerve - carries motor, sensory and autonomic
What do somatic nerves of spinal nerves do?
Supply voluntary muscles and body wall structures - bones and joints
What do the autonomic fibres of spinal nerves do?
Supply involuntary structures - organs, involuntary muscles and glands
Explain sympathetic nerve fibres
Emerge from spinal cord from lateral horn cells
Located between spinal segments T1-L2
Has preganglionic and postganglionic fibres (unmyelinated)
What are the differences between the autonomic and somatic spinal nerve pathways?
Autonomic had pre and post ganglionic fibres - 1 synapse
Somatic has no ganglia
What horn is the origin of somatic cell bodies?
Ventral horn
Which spinal cord segments give rise to somatic cell bodies?
C1-Cc3-5
All spinal nerves
What is the white ramus and grey ramus?
White - preganglionic and myelinated
Grey - postganglionic and unmyelinated
What do white ramus communicates carry?
Sympathetic fibres to the sympathetic chain
What is another name for sympathetic chain?
paravertebral ganglia
What are the 3 things the sympathetic chain can do?
1 - synapse in a chain ganglion at the same spinal level
2 - ascend and descend
3 - run through chain without synapsing and synapse instead in a prevertebral ganglion in the abdomen = splanchnic nerves
Where are the parasympathetic nerves carried?
In some cranial nerves (vagus) and in spinal nerves S2-4
Arise in lateral horn in the distal end of the spinal cord
What are the large autonomic plexuses?
Cardiac, pulmonary, coeliac, superior hypogastric and inferior hypogastric
What type of supply is the upper and lower limbs?
Only sympathetic autonomic innervation
What is lymph?
Plasma filtrate which has leaked from capillary beds due to high hydrostatic pressures
What is the function of the lymphatic system?
Return this to circulatory system
Important in immunity and cancer spread
What tissue and organs do not have lymphatic drainage?
Cartilage, eyes, inner ear, brain and spinal cord
What cell type is lymphoid node made up of?
Lymphocytes
What does the term sentinel node mean?
First lymph node to which cancer cells are most likely to spread from primary tumour
What carries the lymphatic fluid back to venous circulation?
Thoracic duct and right lymphatic duct
Where does the thoracic duct commence?
Vertebral level of L1 as the cisterna chyli
Describe the thoracic duct
Ascends between the azygos vein and the aorta on the right side of the posterior thoracic wall below vertebra level T4
Drains into the medial end of the left subclavian vein
