Spine Flashcards
Ligamentum Flavum
Limits end range of vertebral flexion
Supraspinous/Interspinous Ligaments
Limits Flexion
Intertransverse Ligament
Limits contralateral flexion and forward flexion
Anterior Longitudinal Ligament
Limits extension or excessive lordosis in cervical & lumbar regions
Reinforces anterior sides of intervertebral discs
Posterior Longitudinal Ligament
Limits flexion and reinforces posterior sides of intervertebral discs
Capsules of Apophyseal Joints
Strengthens apophyseal joints
C1 Facets
Superior= large, concave (accept condyles)
Inferior= Flat
Facet for Dens
C2 Facets
Superior= Flat
Inferior = typical cervical (face anterior & inferior) at 45 degrees (between horizontal & frontal planes)
C3-C6 Facets
Superior= face posterior & superior
Inferior= face anterior & inferior
Upper Lumbar Facets (L1, L2 & kinda L3)
Superior= nearly vertical (sagittal plane)
Inferior= reciprocal to match
Lower Lumbar Facets (L4, L5)
Superior= midway between frontal & sagittal plane
Inferior= reciprocal to match
L5-S1 Facet
Frontal Plane (for anterior/posterior stability)
Cervical Spine C1
“Atlas”
Suports the head
No rotation here
Cervical Spine C2
“Axis”
Dens for rotation (No motion)
Cruciform, Transverse & Alar Ligament
Cervical Spine C3-C7
45 degree angle at Facet Joints!!
C7 is Most Prominent
Thoracic Spine T1
Elongated spinous process
Thoracic Spine T2-T9
Posteriorly directed pedicles to reduce size of vertebral canal & larger transverse processes
Articular facets are nearly vertical
Thoracic Spine T10-T12
No articulation with transverse processes
Lumbar Spine L1-L5
Wide bodies to support weight and broad spinous process
Articular facets are nearly vertical (prevent shear force)
Sacrum
Transmit weight of vertebral column to pelvis
Approximation of Joint Surfaces
facet surface tends to move closer to its partner facet -> usually by a compression force
ex: axial rotation between L1 & L2 typically causes an approximation of the contralateral apophyseal joint
Separation (gapping) between joint surfaces
facet surface tends to move away from its partner facet -> usually by a distraction force
ex: therapeutic traction as a a method of decompression in apophyseal joints
Sliding (gliding) between joint surfaces
facets translates in a linear or curvilinear direction relative to another articular facet -> caused by a force directed tangential to the joint forces
ex: flexion-extension of the mid-to-lower cervical spine
How do Spinous & Transverse Processes affect spinal movement?
They act as levers to increase the mechanical advantage of muscles & ligaments
How do Apophyseal Joints affect spinal movement?
They guide intervertebral motion (act like “railroad tracks”)
How do Interbody Joints affect spinal movement?
They absorb shock and distribute loads. The greater the space of discs, the greater the potential movement
Horizontal Facets effect on rotation
Axial Rotation can occur
Vertical Facets effect on rotation
Blocks rotation
General Kinematics - Lateral Flexion
Compression & Shortening on concave side
(Ipsilateral)
Tension & Lengthening on convex side
(contralateral)
General Kinematics - Flexion
Anterior Structures shorten/compress
Posterior Structures lengthen/create tensile stress
General Kinematics - Extension
Anterior Structures lengthen/create tensile stress
Posterior Structures shorten/compress
General Kinematics - Rotation
Direction the spinous process moves with rotation
Atlanto-occipital joint (C0-C1) Kinematics
Flexion/extension (10-30 degrees)
Slight lateral flexion
No Rotation
Atlanto-axial joint (C1-C2) Kinematics
Facets in Horizontal Plane
50% of Axial Rotation!!!
Flexion/Extension
Limited to no Lateral Flexion
Intracervical Apophyseal joints (C2-C7) Kinematics
Facets at 45 degrees
Flexion/Extension (~130-135 degrees)
Lateral Flexion
Rotation
Craniocervical Movement: Protraction
Upper cervical extension
Lower cervical flexion
Craniocervical Movement: Retraction
Upper cervical flexion
Lower cervical extension
Thoracic Vertebrae Kinematics
Flexion/Extension (very limited in T1-T6 because of facet orientation)
Axial Rotation (decreases as you move caudally)
Lateral Flexion (facets would allow for unlimited motion but its reduced by rib attachments)
Coupled lateral flexion & rotation
C7 Facet
Facets more similar to Thoracic
T1 Facets
Full superior costal facet for 1st rib
Inferior= partial costal facet for 2nd rib
T10-T12 Facets
Single full costal facet for 10th, 11th, & 12th ribs
None with Transverse Processes
T2-T9 facets
Costal Facet= nearly 90 degrees
Articular Facets= nearly vertical (almost Frontal Plane)
meaning it blocks rotation
Rib Arthrokinematics
Upper Ribs (1-6) are primarily Sagittal Plane -> so inhalation is anterior/superior movement & exhalation is posterior/inferior movement
Lower Ribs (7-12) are primarily Frontal Plane -> so during inhalation ribs move lateral & superior
& exhalation is medial & inferior
Interbody Joints
(two vertebrae + disc)
Nucleus Pulposus = Shock absorber (type 2 collagen) & proteoglycans
Annulus Fibrosis = concentric rings of collagen fibers
