OCMM Midline And Paired Bones Flashcards
What is the motion of the occiput, sphenoid, ethmoid and vomer?
Rotate about a transverse axis, flexion and extension
What are the 4 parts of the ethmoid bone?
Cribiform plate, perpendicular plate, 2 lateral masses
Which 5 bones does the vomer articulate with?
Sphenoid, ethmoid, septal cartilage, maxillae and palatines
The sphenoid drives what?
Vomer motion
What happens to the ethmoid and vomer when the SBS is in flexion?
The ethmoid will move in the same direction as the occiput and the vomer will move in the same direction as the sphenoid
Which way do midline bones move?
Flexion/extension; normally rotate about a transverse axis in a anterior/posterior direction
Which way do paired bones move?
Internal/external rotation; usually move about AP axis in a lateral motion (coronal plane), labeled external/internal rotation (flexion-extension)
What 5 other bones does the parietal bone articulate with?
Occiput, frontal, sphenoid, temporal and opposite parietal
Which sutures are present in the parietal bone?
Sagittal, coronal, parietosquamous, parietomastoid, lambda, sphenoparietal
Which bones in the only one that contacts all 4 fontanelles?
The parietal bone
What does the temporal bone articulate with?
Occiput, parietal, sphenoid, zygoma, mandible
Which sutures are present on the temporal bone?
Occipitomastoid, sphenotemporal, parietosquamous, parietomastoid, temporozygomatic, TMJ
The eustachian tube exits between which two bones?
Sphenoid and temporal bones
Which muscles attach to the temporal bone?
Splenius capitus, longissimus capitus, digastric, STC, stylohyoid, styloglossus, masseter
What does the frontal bone articulate with?
Parietals, sphenoid, zygoma, lacrimals, ethmoid, maxillae, nasals
Sphenoid flexion and extension moves which bone?
The frontal bones
What is the axis for torsion?
Sagittal (AP); motion of the sphenoid and occiput happens in opposite directions about the axis
Torsions are named for what?
The higher greater wing of the sphenoid
Sidebending rotations are named for what?
Named for the convexity developed in the cranium
Which axes are involved in sidebending rotation?
One sagittal axis (AP; motion happens in the same direction about this axis) and two axes are vertical (superior-inferior; motion happens in opposite directions)
What is a vertical strain named for?
The direction of the base of the sphenoid
What are the axes involved in vertical strains?
Two transverse (horizontal); motion happens in the same direction about these axes
What are lateral strains named for?
Name for the direction of the base of the sphenoid
Which axes are involved in lateral strains?
Two vertical; motion happens in the same direction about these axes
What is a compression?
Occurs on a sagittal axis (AP); due to significant trauma, depression or anxiety; may mimic other strain patterns
How does SBS flexion influence the sacrum?
Pulls up on the dural sleeve of the cord (attaches at the occiput and S2), sacral base moves posteriorly, called counternutation
How does SBS extension influence the sacrum?
Sacral nutation; nutation means nodding (forward towards the nuts)
Where would trauma occur to cause a sidebending rotation?
Directly at the SBS
Where would trauma occur to cause a lateral strain?
Anterior or posterior to the SBS
Where would trauma occur to cause a vertical strain?
Superior or inferior force anterior or posterior to the SBS
Where would trauma occur to cause torsion?
Rotational force anterior or posterior to the SBS
