Paired Bones Flashcards
Movement of occiput, sphenoid, ethmoid and vomer
- rotate about a transverse axis
- flexion is paired with inhalation
- extension is paired with exhalation
SBS extension is paired with inhalation or exhalation?
exhalation
SBS flexion is paired with? Moves?
- inhalation
- SBS moves superiorly with increased angle inferiorly
Paired bones of the cranial vault and the temporals
- frontals, parietals, temporals
- rotate externally during cranial flexion
Paired bones of the face
- maxilla, palatines and zygomae
- rotate externally during cranial flexion
Parietal bone articulates with 5 other bones what are they?
- occiput
- frontal
- sphenoid
- temporal
- opposite parietal (paired!)
- only bone that contacts all 4 fontanelles
Parietal bone outer surface
- upper temporal ridge (attachment of the temporal fascia)
- lower temporal ridge (origin of the temporalis muscle)
- temporalis fossae (filled by the temporal muscle)
Parietal Bone Inner surface
- sagittal sulcus: a groove along the sagittal sutures in which the sagittal sinus runs
- groove of the middle meningeal artery
- the bevel changes along the coronal and lambdoidal articulations
- lateral part of the groove for the transverse sinus–carries the marginal insertion of the tentorium cerebelli
Parietals axis of motion
- bevel change midway along sagittal and lambdoidal sutures creates a hinge for the AP axis of motion (coronal plane)
- external rotation of the parietals occurs with SBS flexion
- inferior borders move laterally
- superior borders move medially and inferiorly
- pterion, asterion and squamous sutures move laterally
- sagittal sutures move slightly inferiorly
Parietal bone External rotation
- sagittal articulation moves inferiorly
- temporal articulation moves laterally
- cranium widens laterally
Parietal bone internal rotation
- sagittal articulation moves superiorly
- temporal articulation moves medially
- cranium narrows laterally
Mechanical joint related pain associated with parietal bone SD
- cranial synostosis: premature closure of the sutures (coronal, sagittal, lambdoidal)
- head pain: pain along a suture
- OM and asterion often involved in tension headaches
- pterion often involved in temporal headaches
- parietosquamous
organ/myofascial dysfunction related to parietal bone SD
- middle meningeal artery trauma: giant cell arteritis–diagnosed by contrast-enhanced, high resolution MRI
- Head, face and tooth pain–temporal SD
Sagittal syntosis
- most common form
- premature fusion of the sagittal sutures restricts the transverse growth of the skull
Lambdoid synostosis
- form of synostosis most commonly mistaken for posterior positional deformational plagiocephaly and must be closely evaluated
- unilateral lambdoid synostosis results in flatterning of the back of the head on the affected side as well as compensatory growth of the mastoid process on the same side (ipsilateral mastoid blue)
- leads to a characteristic and unique “tilt” in the cranial base
- differentiates it from positional/deformational plagiocephaly
- The ear on the affected side is often deviated back and toward the fused suture
- one of the rarest types
Temporal Bone Squamous Portion contains
-zygomatic process–facial injury affects temporal bone