1 C Spine Biomechanics Flashcards
What is normal lordosis extension of the C spine?
- 30-35 degrees
- Approximates facets joints and narrows down central canal of spine
- potential loading and challenges with degeneration
What is the Crainiocervical motion for flexion?
- Combined 40-50
- OA 5
- AA 5
- Lower Cervical 35-40
What is the Crainiocervical motion for Extension?
- Combined 70-80
- OA 10
- AA 10
- Lower Cervical 55-60
What is the Crainiocervical motion for Rotation?
- Combined 65-75
- OA —
- AA 35-45
- Lower Cervical 30-35
What is the Craniocervical motion for sidebending?
- Combined 35-40
- OA 5
- AA –
- Lower Cervical 30-35
Where is the greatest segmental motion and most common site for DJD?
- C4-5
- C5-6
- C6-7
Type 1 mechanics C Spine
Rotation and sidebend occur in opposite directions
Upper C spine
Type 2 Mechanics C Spine
Roation and sidebend occure on the side sides
Lower C spine
Type 3 Mechanics
Motion in 1 plane reduces motion in all remaining planes
Ex) head flexion causes less rotation of the head (isolates C1-2)
Describe the Arthrokinematics of the OA joint with Flexion
Occiptal condyles roll ANTERIOR and glide POSTERIOR
“YES/nodding”
Describe the Arthrokinematics of the OA joint with Extension
Occipital condyles roll POSTERIOR and glide ANTERIOR
“YES/nodding”
Limits to movement of the OA joint?
Articular capules, OA membranes, Ligaments
Describe the movements of the AA joint
“No/Shaking”
Full rotation can cause stretch to artieries
Twist and turn around the dens
What are the limits to the AA joint
- Alar ligaments
- apophyseal joint tension
- Muscles
What ist he function of the Alar Ligament?
- Stabilizes occiput with rotation
- Lateral dens to medial aspect of occiptal condyle
What is the function of the Transverse ligament?
- Prevents anterior migration C1 on C2
- Lhermitte’s sign - Reuslts in potential cord sign/electrical shock down arms/backs/letgs
- Holds C1 against the dens
What is the funciton of the Tectoral membrane?
Stability in Upper cervical region
PLL
Describe the Vertebral and Carotid Arteries with movement of the neck
- VERTEBRAL ARTERY
- Enter the foramen at C6 and up to C2
- Not conclusive if Ipsilateral or Contralateral BF is affected
CAROTID ARTERY
- LEss affected by movement
- Impaired by CV disease, infection, trauma
What is the role of the Facet and ZPJ during flexion and exension?
- Facilitate sluding motion + combined moviton of rotation and sidebending
45 degree angle
Describe Extension of the Lower Cervical Spine
- INFERIOR articular facet slide POSTERIOR and INFERIOR on superior articular facet
- Maximized contact with facet and ZPJ
- CLOSED PACKED POSITION
Describe flexion of the lower cervical spine
- OPEN PACKED
- Superior/Anterior sliding of facet (opening)
- Maximizes space of spinal cord in flexion
Describe the movement of Protraction/Retraction
Protraction: Flexes LOWER C spine and extends UPPER C spine
Retraction: Flexion in UPPER C spine and extension LOWER C Spine
Desribe Laterl Flexion and Rotation of the Lower C spine
- 30-35 degrees of lateral flexion
- do not occur in isolation (work together)
Rotation (R): to one side slides R facet POSTERIOR and INFERIOR
CLOSING motion
Sidebeind (R): Posterior inferior glide of R facet . Anterior superior glide of L facet
Closing on R, opening on L
What is upper Crossed Syndrome/postural dysfunction?
- Related to protration (forward head position)
- causes:
- Increased upper trap strain + cervical extensors
- tight
- weakness in cervical deep flexors
- Muscle imbalance
