Neurology Anatomy Flashcards
Which muscles make up the Extrinsic back muscles?
Trapezius
Levator scapulae
Rhomboids (major + minor)
Latissimus Dorsi
What is the functions of the extrinsic back muscles?
- Attach back to pectoral girdle (have attachment point somewhere outwith back)
- Move upper limb
Main innervation of the extrinsic back muscles?
Anterior rami of cervical spinal nerves
Exception = trapezius –> spinal accessory
What are the 2 main groups of Intrinsic back muscles?
Erector spinae (superficial)
Transversospinalis (deep)
What is the function of the intrinsic back muscles?
Maintain back posture
Move spine
Where is the erector spinae muscles located?
3 vertical groups located lateral to the spine
What are the common inferior and superior attachments of the erector spinae muscles?
Inferior - sacrum, iliac crest
Superior - rib, transverse process of vertebra, spinous process of vertebra
Where is the Transversospinalis intrinsic back muscle located?
Within the grooves between the transverse & spinous processes
What is the nerve supply of the intrinsic back muscles?
Segmental nerve supply (as per myotome/dermatome)
Posterior rami branches (cervical, thoracic, lumbar)
What are the three main muscles of the anterolateral abdominal wall (superficial to deep)?
External oblique
Internal oblique
Transverse abdominis
What are the main movements of the spine by erector spinae and transversospinalis?
Maintain posture + support
Extension of spine (erector spinae contracts bilaterally)
Unilateral contraction = lateral flexion
What are the sections of the vertebral column?
Cervical C1-C7 Thoracic T1-T12 Lumbar L1-L5 Sacrum (5 sacral) Coccyx (4 coxxygeal)
33 vertebrae in total
How does the size of vertebrae change as you travel down the spine?
Become larger as they become more weight bearing
Sacrum + Coccyx become smaller again once weight transferred to hip bones
What is the functions of the vertebral column?
Support head + trunk when upright
Protect spinal cord (+ nerves)
Allow movement
Explain the development of the curvatures of the vertebral column
As a fetus the spine is a continuous curve which slowly starts to develop separate curvatures as the child begins to walk and weight bear
Adults have 2 primary lordosis curvatures (cervical, sacral) and 2 secondary kyphosis (thoracic, lumbar)
What does the vertebral arch consist of?
Pedicle x2
Lamina x2
What is the function of the inferior and superior articular process of a vertebra?
Mobility with adjacent vertebrae via synovial facet joint
Where in the spine are spinal nerves found?
Intervertebral Foramen
What pathology can common affect the facet joint between articular processes?
Arthritis
What is an Intervertebral disc?
Sits between the bodies of adjacent vertebrae
Strong attachment
Between which vertebrae are there no intervertebral discs?
C1-C2
Sacrum
Coccyx
What is the formation of the intervertebral disc?
Outer fibrous ring - Annulus Fibrosus (strong)
Inner soft pulp - Nucleus Pulposus (flexibility + protection)
How much of the length of the spine is made up by intervertebral discs?
20-25%
What are the three main ligaments found within the spinal cavity?
Ligamentum flavum
Posterior longitudinal ligament
Anterior longitudinal ligament
What is the function of the anterior longitudinal ligament?
Stronger support for disc
Prevents over-extension of spine
Broad + strong
What is the function of the Posterior Longitudinal ligament?
Prevents over-flexion of spine
True or False:
Posterior longitudinal ligament provides MORE support for the disc than the anterior longitudinal ligament
FALSE
Posterior longitudinal ligament is narrow + weak
What is the function of the ligamentum flavum?
Connects adjacent laminae posterior to the spinal cord
Where does the supraspinous ligaments connect?
Connects tips of spinous process
Strong, fibrous
Where does the Interspinous ligament connect?
Connect superior and inferior surfaces of adjacent spinous processes
Weak, membranous sheet-like
Which vertebrae does not have a body or spinous process?
C1 - Atlas
Has posterior arch and anterior arch instead
Which vertebrae has an odontoid process?
C2 - Axis
Projects superiorly from body and articulates with C1
What is the main movement of the Atlanto-axial joints?
Rotation
What are the four stages of cervical vertebrae dislocation?
1 - flexion sprain
2 - anterior subluxation, 25% translation
3 - 50% translation
4 - complete dislocation (facet jumped over to other side + locked in place)
At what levels does the spinal cord begin and end?
Begins at foramen magnum - C1 segment
Ends around vertebral level L1/L2 (conus medullaris)
What is a Laminectomy?
Used to access spinal canal, posterior exposure of the spinal cord and/or spinal roots
Relieve pressure on spinal cord or nerve roots
What symptoms will patients complain of with somatic general sensory pathology?
Pain (neuralgia), pins & needles (paraesthesia), numbness, sensitivity, thermal (hot or cold), loss of coordination/balance/clumsiness
What symptoms will patients complain of with somatic motor pathology?
Muscle stiffness/tightness/spasm, muscle floppiness or looseness, muscular weakness, loss of coordination/balance/clumsiness
What are the main dermatomes of the upper limb?
C5, C6, C7, C8, T1, T2
True or False:
C1 does not have a dermatome
TRUE
C1 only has motor function/myotome
What are the main dermatomes of the lower limb?
L1 - S5
What is the arrangement of dermatomes of the lower limb?
Goes down the front (L1 - L5)
Up the back (S1 - S3)
Then circles around the groin (S3, 4, 5)
True or False:
The dorsal roots (posterior) carry sensory information only
TRUE
Ventral roots carry motor information
What are the end named nerves of the Brachial Plexus?
Musculocutaneous Axillary Median Radian Ulnar
From which cervical nerves does the brachial plexus arise from?
C5 - T1
What is the sensory nerve supply of the anterolateral neck skin and posterior scalp & neck?
Anterolateral neck = Cervical plexus (C1-4)
Posteriorly - posterior rami of C2-C8
What is the mneumonic for the named nerves of the cervical plexus supplying the anterolateral neck skin?
Little Goats Treat Softly
L - Lesser occipital nerve
G - Greater auricular nerve
T - Transverse cervical nerve
S - Supraclavicular nerve