Anat of back Flashcards
How many cervical vertebrae are there?
7
How many thoracic vertebrae are there?
12
How many lumbar vertebrae are there?
5
How many sacral vertebrae are there?
5
How many coccygeal vertebrae are there?
3-4
What are bony landmarks of the spine?
Vertebral prominence - C7 spinous process
Highest point of iliac crest - crosses L4 and L4-L5 IV disc
Inferior angle of scapula - T7
Posterior superior iliac spine - S2
What are the 7 processes of the vertebra?
2 superior articular processes
1 spinous process
2 transverse processes
2 inferior articular processes
What are the typical vertebrae with a body, arch, and 7 processes?
C3-L5
Why is C1 considered an atypical vertebrae?
No body or spine
Superior facet that forms atlanto-occipital joint
Inferior facet forms atlantoaxial joint
What is typically fractures in a fracture of atlas?
Anterior and/or posterior arches of C1
Between which two vertebrae is there no IV disc?
C1 and C2
What is C2 considered an atypical vertebrae?
Odontoid/dens process - pivot for head
Superior articular facet - antlantoaxial joint
Bifid spinous process - muscular attachement
What is fracture and dislocation most often seen on C2?
Bony column between superior and inferior processes
What is the function of anterior atlanto-occipital ligament?
Connects foramen magnum of skull to atlas
Continues as anterior longitudinal ligament
What is the function of apical ligament?
Attaches dens of C2 to anterior part of foramen magnum
What is the function of alar ligment?
Attaches dens of C2 to occipital condyles
What will occur with damage to the alar ligament?
Increase in axial rotation between occiput and atlas axis
What is the function of the transverse ligment?
Between ring of atlas to keep odontoid process in contact with atlas. Prevents anterior displacement of C1 over C2. Prevents posterior migration of odontoid process onto spinal cord
What will occur with a transverse ligament tear?
Increase flexion angle of head
What is the function of the anterior longitudinal ligament?
Limit hyperextension of spine
Maintain stability between vertebral bodies
What is the function of posterior longitudinal ligament?
Limits flexion of spine
Stabilizes vertebral column during flexion
What is the function of ligamentum flavum?
Stabilizes vertebral arch joint in flexion
What can occur with hypertrophy of ligamentum flavum?
Stenosis
What is the function of nuchal ligament and where does it end?
Limits flexion of cervical spine, stability to neck
C7
What are general characteristics of cervical vertebrae?
Foramen transversarium
Large, triangular vertebral foramen
Small and wide body
Bifid spinous process
What is the unique characteristic of C7?
Long spine
What is the function of foramen transversarium?
Passageway for vertebral arteries, veins, and sympathetic plexus
What are general characteristics of the thoracic spine?
1-2 facets for articulation with head of rib
Long spinous process with posteroinferior slope
Long and strong transverse process that gets smaller down the spine
Small and circular vertebral foramen
What are general characteristics of the lumbar spine?
Massive, kidney shaped body
Triangular foramen
Long, slender transverse process
Supero-inferomammillary facets on articular processes
Short, sturdy, and broad spinous process
What occurs with a laminectomy?
Surgical excision of one or more spinous processes
What causes a cervical rib?
Overdevelopment of C7 transverse processes
What is the intervertebral joint?
Between to vertebral bodies
Cartilaginous - symphyses
Weight bearing, strength, movement
What is the zygapophysial joint?
Between processes of vertebrae
Plane synovial
Gliding movement
What are the movements done by the spine?
Extension (lean back)
Flexion (bow)
Lateral flexion (lean to the side)
Lateral extension (upright)
Rotation of head and neck
Rotation of upper trunk
What is the most inferior functional IV disc?
L5-S1
What are the two parts of an IV disc?
Outer - annulus fibrosus
Inner - nucleus pulposus
What is the annulus fibrosus?
Concentric lamellae of fibrocartilage
What are the characteristics of nucleus pulposus?
Avascular
Gelatinous
Shock absorber - resilient
What happens to the nucleus pulposus with age?
Dehydrates
Looses elastin and proteoglycans, while gaining collagen
Becomes dryer and granular
What is the supraspinatus ligament and its function?
From C7 to sacrum, continues from nuchal ligament
Limits hyperflexion
What is the function of the interspinous ligament?
Connect adjoining spinous processes of vertebae
When does the cervical lordosis begin to form and why?
Around 6 mo of infancy
When head control develops
When does the lumbar lordosis begin to form and why?
Around 1 year
With standing and walking
What is kyphosis?
Abnormal increase in thoracic curvature - hunch/humpback
What are causes of kyphosis?
Osteoporosis, compression fracture, disc degeneration
What is lordosis?
Abnormal increase of lumbar curvature - sway/hollow back
What are causes lordosis?
Weak trunk muscles, pregnancy, obesity, spondylolisthesis (pot belly)
What is scoliosis?
Abnormal lateral curvature of spine with rotation of vertebrae
What cause scoliosis?
Weakness of intrinsic muscles of back, congenital or habitual from poor posture, leg length discrepancy, hip disease
What are clinical features of Jefferson’s/burst fracture of C1?
Neck pain, cervical muscle spasm, limited neck ROM, LOC, vertigo (may affect vertebral artery)
What fracture can occur with hyperextension of the head and neck?
Fracture of C2 - Hangman’s fracture
When are compression fractures of vertebrae typically seen?
Osteoporosis
Bone cancer/metastasis
What part of the spine is commonly affected by compression fractures?
Thoracic
What is a wedge compression fracture of vertebrae?
Anterior part of body collapses
Hyperflexion injury
Common in cervical spine
What is a crush fracture of vertebrae?
Break of entire vertebra
What are the subtypes of vertebral compression fractures?
Wedge
Crush
Burst
What is a burst fracture of vertebrae?
Loss of height in both front and back wall of body
Can cause neurologic deficits
What are clinical features of whiplash injury?
Neck pain, stiffness, limited ROM of neck, neurological deficits
What is spondylosis?
Stress fracture of column bones connecting superior and inferior processes
What is spondylolisthesis and its common cause?
Forward displacement of vertebra
Spondylosis
What are clinical features of spondylolysis and spondylolistheisis?
Acute pain after athletic activity, radiation of pain into buttocks, symptoms relieved with rest
What are the characteristics and function of the superficial back muscles?
Connect upper limb to vertebral column
What are the superficial back muscles?
Trapezius
Latissimus dorsi
Levator scapulae
Rhomboid minor and major
What is the function of the intermediate back muscles?
Involved with respiration
What is the function of deep back muscles?
Vertebral column
Erector spinae
What nerve innervates the trapezius?
Spinal accessory CNXI
What nerve innervates the latissimus dorsi?
Thoracodorsal nerve from posterior cord of brachial plexus
What muscles are innervated by the dorsal scapular nerve?
Levator scapulae
Rhomboid minor
Rhomboid major
What is the importance of the auscultatory triangle of the back?
Only area of back not covered by muscle. Breath sounds are easily heard with stethoscope.
What are the muscles that make up the erector spinae?
Spinalis
Longissimus
Iliocostalis
What is the action of the erector spinae muscles?
Extension and lateral flexion of the vertebral column
What is the innervation of the erector spinae muscles?
Posterior/dorsal rami of spinal nerves
At what level does the spinal cord end?
At L1-L2 IV disc
Where does the dural sac end?
S2
Where does the dura mater attach?
Coccyx
What are clinical signs of a herniated/prolapsed IV disc?
Localized pain that radiates into region affected by nerve roots. Tingling, weakness, paralysis
What are clinical signs of cauda equina impingement?
Loss of bladder and bowel control. Sexual dysfunction
What is the area of lumbar puncture and how do you find it?
Above or below L4 - vertebra at level of superior iliac crest
When is lumbar puncture not performed?
In the presence of increased cranial pressure
What layers does the needle go through during lumbar puncture?
Skin, subcutaneous tissue and fascia, supraspinous ligament, interspinous ligament, flavum, dura, arachnoid, into subarachnoid space
What layers does the needle go through for epidural anesthesia?
Skin, subcutaneous tissue and fascia, supraspinous ligament, interspinous ligament, flavum, into epidural space
Why is epidural anesthesia done in the epidural space?
Presence of vasculature
What are the contents of the occipital triangle?
Vertebral artery
First cervical nerve
Suboccipital plexus of veins
What makes up the suboccipital plexus of veins?
Occipital vein
Transverse sinus through emissary veins
Blood from neighboring muscles
Internal vertebral venous plexus
Where is a suboccipital/cisternal puncture done?
Midline just above spine of axis(C2) through suboccipital triangle into cisterna magna
When would a sub
