Anatomy - The Spine and Back Flashcards
Muscles of the spine
Serratus posterior 2 splenius muscles Erector spinae muscle mass Mutifidus Rotatores Semispinalis
Serratus posterior
Both superior and inferior found in fascial region
Function of splenius muscles
Movement of neck
Lateral flexion
Rotation
Common attachment of erector spine muscles
Ilium, inferiorly
Order of Erector spinae muscles
Most lateral is iliocostalis, attaches to ribs, middle is longissimus and most medial is spinalis
How else can we divide erector spinae muscles
Region of spine: cervicalis, thoracic, lumbaris
Why are the erector supine muscles referred to as a muscle mass
Hundreds of small muscles can work independently of each other to create more refined movements of the vertebral column
Where id lumbodorsal fascia found
Over L4 - S1 region
Multifidus
Found deep to lumbar dorsal fascia
Traingular shaped
What muscles does multifidus work with
Rotatores and semispinalis - responsible for fine rotational movement of one vertebra on another
Innervation from dorsal rams
Each level receives innervation from posterior (dorsal) ramus - spread to level and those above and beyond
Why is there a risk if we damage a small area of erector spinalae muscles
Brain receives afferent signals from 3 different nerves
Infl response to damaged erector spinalae muscles
Muscle spasm to protect damaged area
Muscle fibres on unaffected side become stretched as the damaged side contracts and will contract in response to being stretched so muscles on opposite side in spasm
Where is the spin al cord found
Vertebral foramen
What happens if the NP herniates posteriorly
Presses on spinal cord
What happens if the NP herniates laterally
Presses in spinal nerve or rami
Ligaments of the spine
Anterior longitudinal ligament Posterior longitudinal ligament Supt-spinous ligament Interspinous ligament Ligamentum flavum
Longitudinal ligaments of spine
Both anterior and posterior protect vertebral column and discs
Supraspinous ligament - variable
Variable along vertebral column
Replaced by ligament niche in cervical region
Replaced by criss-crossing fibres (decussation) of erector spinae muscles in between L4-S1
Ligamentum nuchae
Relaces supraspinous ligament in cervical region as is more elastic
Why is supraspinous ligament replaced in between L4 - S1
Allows greater movemmet in that region
Greater flexion required e.g. touching toes
-ve is AF subjected to greater degree of wear and tear ao herniation more likely
Function of supraspinous ligament
Prevent flexion between each vertebra by attaching to spinous processes and preventing them from moveing too far apart.
Interspinous ligament
Sits in between the spinous processs
Where is ligamentum flavum found
Sits in deep aspect of neural arch, between spinous process
Ligamentum flavum function
Quite elastic, prevents movements of neural arches from each other, limiting flexion
Vertebral foramen
Space between neural arches and vertebral bodies
What is the spinal cord surrounded by
Meningeal layers
Meningeal layers of spine
Dura mater
Arachnoid mater
Pia mater
Dura mater
Most superficial meningeal layer
Fibrous and tough
Arachnoid mater
Deep to dura mater
Light and cobweb-like
Pia mater
Deep to arachnoid mater
Plastered to spine
Where is CSF found
Below arachnoid mater in sub-arachnoid space
Usually pushes arachnoid mater to dura mater
Spinal cord length in adults
Base of skull to L1
Spinal cord length in children
Base of skull to L3 as spinal cord doesn’t grow at same rate as vertebral column
Conus medullaris
Terminal end of spinal cord
Filum terminalis
Terminal branch of spinal cord
Where is cauda equina found
Nerve roots from lower portion of spinal cord
Lines visible on a lateral spinal x-ray
Anterior vertebral line
Posterior vertebral line
Spino-laminar line
Posterior spinous line
What is the L4/5 disc lined up with
Top of iliac crests
What does T12 line up with
T12
Where does each nerve root come out
Below level of vertebra expect for cervical vertebrae (on top) as there are 7 vertebrae but 8 nerve roots
