Cervical Spine Flashcards
Norm values of cervical flex, ext, lat flex, and rot
Flex: 60
Ext: 75
Lat flex: 45
Rot: 80
General characteristics of cervical vertebrae
-small
-spinal process is short and bifid
-foramen in each TP (foramen transversarium)
What does the vertebral a supply? Where does it enter?
-upper SC, cerebellum, posterior part of brain
-skips C7 and enters C6
C1 characteristics
-atlas
-shaped like a ring
-no vertebral body or spinous process
-2 large lateral masses that create large TP for muscle attachments
C2 characteristics and function
-axis
-characteristics: anterior portion of body extends inferiorly, vertical projection (dens)
-functions: provide motion into axial rot, transmit combined load of head and atlas
What ligaments limit amount of head rot? Location?
alar ligaments; sides of dens to lateral margins of foramen magnum
What ligament prevents posterior and anterior displacement?
transverse ligament of atlas
Atlanto-occipital joint characteristics
-superior facets of atlas articulates w/ convex occipital condyles
-true synovial joint
-allows head nod up and down
Atlanto-axial joints characteristics
-2 lateral and 1 median
-where 50% of rot happens
What is the tectorial membrane?
continuation of posterior longitudinal lig, covers dens and cruciate lig, inserts at anterior rim of foramen magnum
What is a cruciate ligament?
transverse ligament + superior and inferior longitudinal bands
-superior: transverse to occipital bone
-inferior: transverse lig to body of C2
Base of dens vs on body fracture
-base of dens: transverse lig can go between dens and body and cut off blood supply (cause necrosis)
-body: lig won’t reach where fracture is; better healing process
What happens with a rupture to transverse ligament?
-dens is free -> atlanto-axial subluxation
What is AAI? Who is it seen in? Interventions?
-atlantoaxial instability
-Down Syndrome
-symptomatic (posterior fusion C1 to C2); asymptomatic (precautions to avoid neck injury, regular appts)
How do you rupture alar ligaments?
flexion and rotation of head
Characteristics of C3 to C6 (body, surfaces, joints)
-small rectangular bodies
-superior and inferior body surfaces not as flat as vertebrae
-superior surfaces have uncinate processes articulate with uncovertebral joints or joints of Luschka
-uncovertebral joints add stability
What is Wolff’s law?
bone will grow/strengthen under stress
What causes cervical osteophytes?
-increased compression force on uncovertebral joint
Characteristics C3 to C6 (pedicles, TP, vertebral canal)
pedicles: short and curved posterior-lateral, very thin laminae extends posterior-medial from each pedicle
TP: terminates in anterior and posterior tubercle
Vertebral canal: large triangle, accommodates SC w/ cervical and brachial plexus formation
What angle are articular processes of typical C3 to C6?
40-60 degrees from horizontal
C7 characteristics
-vertebral prominens
-only atypical segment
-large TP
-large single pointed SP
-sometimes presents hypertrophic anterior tubercle that accommodates an extra rib (can impinge brachial plexus)
Main functions, innervation, vascular supply of suboccipital muscles
-extend and rotate the head at the atlantoaxial joint
-posterior ramus of 1st cervical n
-branches of vertebral and occipital arteries
What are the borders of the suboccipital triangle
-medial border: rectus capitis posterior major
-lateral border: obliquus capitis superior
-inferior border: obliquus capitis inferior
Contents of suboccipital triangle
posterior ramus of C1 (suboccipital n), vertebral a and associated veins
Rectus capitis posterior major OIIA
origin: spinous process of C2
Insertion: lateral portion of occipital below inferior nuchal line
Action: extension of head and rot
Rectus capitis posterior minor OIIA
Origin: posterior tubercle of C1
Insertion: medial portion of occipital below inferior nuchal line and dura mater
Action: ext of head
Obliquus capitis superior OIIA
Origin: TP of C1
Insertion: occipital between superior and inferior line
Action: extends
Obliquus capitis inferior OIIA
Origin: SP of C2
Insertion: TP of C1
Action: rotation of head
