The Head: musculoskeletal

Question 1

axial skeleton

Answer 1

skull

vertebral column

thoracic cage

Question 2

The Skull Characterists

Answer 2

1. approximately 29 bones (11 paired)
2. Structural Joint type: Sutural joint
3. Most sutures form synostosis by middle age
4. Most suture named for connecting bones
5. Greatest increse in size first 2 years up to 5 years
6. Cranium increases capacity until approx. 14-16 years
   
   1. Thickens for another 4-5 years
7. Clinically important region: pterion

Question 3

Pterion

Answer 3

fused sphenoid fontanel

very thin (temple)

meningeal artery deep to pterion

damage can lead to intracranial bleed

Question 4

Two main cranial division

Answer 4

Cranial Bones and Facial Bones

Question 5

Cranial Bones

Answer 5

Form protective shell over brain

approx. 8 flat bones (mostly)

Mostly intramembranous ossification (except the cranial floor)

Question 6

Facial Bones

Answer 6

forms bones of the face

10-14 irregular bones (mostly)

Combo of intramembranous oss. and Endochondral oss.

Question 7

Differences Between Adult Skull and Fetal Skull

Answer 7

1. Proportion
   
   1. fetal -
      
      1. about 1/2 (2 mos) - 1/4 (9 mos) the height of the skeleton
      2. facial bones form 1/8 of the fetal skull
   2. adult -
      
      1. about 1/8 the height of the skeleton
      2. facial bones form 1/3 of the adult skull
2. Shape
   
   1. fetal - rounded
   2. adult - oval
3. Paranasal Sinuses
   
   1. fetal - little or none
   2. adult - present
4. Mastoid and Styloid Process
   
   1. fetal - none
   2. adult - present
5. Fontanels/Syndesmoses v Sutures
6. Frontal bones
   
   1. fetal - two
   2. adult - one
      
      1. may have metopic suture (only seen with x-ray
7. Madible bones
   
   1. fetal - two
   2. adult - one
      
      1. fusion of mandibular symphysis
8. Number of bones
   
   1. fetal - more skull bones
      
      1. 4 occipital, multiple sphenoid and temporal bones
   2. adult -
      
      1. one occipital, sphenoid, and temporal bone

Question 8

Paranasal Sinuses