Lecture 7: The Axial Skeleton
You will see that each bone has special features (overviewed
in section I below) that provide Sites of Attachment (for muscles,
ligaments, tendons, etc.) and Sites of Passage (for blood vessels
and nerves).
Study the prefixes, suffixes, and roots from Lecture 1. These
terms are used repeatedly during the remainder of the course to
describe various parts of all of the major systems. STUDY and KNOW
these word components. They will be an enormous aid in learning
the terms of GROSS Anatomy.
From this point on, there is no substitute for STUDYING. Do
not do it all in one sitting. Constant review and quizzing each
other is the best way to learn it and know it.
One super way to learn all of the terms you are about to be
bombarded with is to make 3'X 5' FLASH CARDS. Write the term on
one side and where it is located on the other. These are extremely
useful when it comes to quizzing yourself in the lab and certainly
in reviewing for quiz/midterm/final. The process of making the
cards themselves is very didactic. Use the boldface terms in each
of the laboratories. I cannot overemphasize how useful flashcards
can be in learning anatomical terminology.
Students often wish they had known of this technique earlier
in the term so they had a simple way to review at the end. Start
now and you will not be one of those students. Believe me, I have
been in that position before. Learn from my mistakes!
I. Different Bone Markings - Essential Terminology
* Depressions and Openings
A. fissure cleft-like opening between adjacent parts of
bones through which vessels & nerves pass
B. foramen hole through which blood vessels, nerves,
ligaments can pass
C. meatus
tunnel-like passageway through a bone
D. sinus
cavity within a bone with narrow opening
E. sulcus
groove or depression that accommodates a soft
structure such as vessels, nerve, tendon
F. fossa
depression in/on a bone; generally at a joint
G. process prominent projection or point of attachment
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* Articular Processes (of the joints)
H. condyle
I. head
large, rounded articular (joint) prominence
rounded articular projection supported by a
more constricted portion of a bone (neck)
J. facet
smooth, flat surface on a bone
* Processes for Attachment (tendons, ligaments, etc.)
K. tubercle
small, rounded process
L. tuberosity
large, rounded, usually rough process
M. trochanter
large, blunt projection; only on the femur
N. line
less prominent ridge than a crest
O. spine
sharp, slender process
P. epicondyle
prominence found "above" a condyle
II. Curvature of the Vertebral Column
A. Normal Curves in Vertebral Column
1. cervical curve - concave posteriorly
2. thoracic curve - convex posteriorly
3. lumbar curve - concave posteriorly
4. sacral-coccygeal curve - convex posteriorly
B. Abnormal Curves of the Vertebral Column
1. kyphosis - exaggerated thoracic curve (hunchback)
2. lordosis - exaggerated lumbar curve (slumping)
3. scoliosis - S-shaped deviation out of midsagittal
plane
III. Identifying Characteristics of Different Vertebrae
A. cervical
*
*
*
*
C1 (atlas) no body, no spine
C2 (axis) bifid spine, dens (head)
C3-6 bifid spine
C7 non-bifid spine, bulges from lower neck
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* transverse foramen (vessel+nerve)
* largest vertebral foramen (down->smaller)
B. thoracic
*
*
*
*
T1 sup. whole facet : inf. demifacet
T2-8 two demifacets; sup. large/inf. small
T9 single superior demifacet
T10-12 whole facet for individual rib
* long, inferior-directed spinous processes
* transverse processes are long and heavy
C. lumbar
* all have largest, thickest bodies
* spinous processes are oblong and heavy
D. sacral
* 5 bones fused at middle age to form sacrum
E. coccygeal
* 3/5 bones fused to form coccyx
IV. Intervertebral Disc
A. Functions
1. absorb stress/shock on the vertebral column
2. provide surface for vertebra to twist
B. Structure
1. annulus fibrosus - outer ring of fibrocartilage
2. nucleus pulposus - inner structure, highly elastic
C. Herniated Disc
1.
2.
3.
4.
nucleus pulposus ruptures through the fibrocartilage
generally ruptures at L3-5 (lower back slipped disc)
most often occurs in posterior direction
can compress spinal nerves and spinal cord
V. Don't Forget That FLASHCARDS Can Save You Time and Energy!!!
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