Human Skeleton Flashcards
1
Q
What is the function of the skeleton?
A
- support
- protection
- movement
- mineral reserve (calcium salts in the skeleton)
- haematopoiesis
2
Q
What are osteons?
A
- aka Haversian system
- layers of bone
- organic 30% (type I collagen)
- inorganic 70% (calcium and phosphate salts)
- ## tensile vs compressive strength
3
Q
Osteoblasts
A
Lay down new bone
4
Q
Osteoclasts
A
Break down old bone
5
Q
Discuss rickets
A
- not enough mineral content in the bone so bone becomes flexible/bendy
- due to vitamin D deficiency
- vitamin D needed for calcium absorption
6
Q
Discuss osteogenesis imperfecta (OI)
A
- congenital genetic disorder
- affects collagen production
- bones become brittle and can fracture easily
7
Q
List some terminology of bone anatomy
A
- diaphysis
- epiphysis
- epiphyseal growth plate
- periosteum
- endosteum
8
Q
Diaphysis
A
- long and tube like
- strong but some flexibility
- mostly made up of compact bone
9
Q
Epiphyses
A
- there are 2 - one at either end of diaphysis
- articular surface for joints
- mostly spongy bone but compact on the surface
10
Q
Epiphyseal growth plate
A
- this separates the diaphysis and epiphysis
- it is where growth occurs
- once growth is complete the plate ossifies and becomes the epiphyseal line
11
Q
Periosteum
A
- a connective tissue later
- covers outer surface of bone
- site of attachment for tendons
12
Q
Endosteum
A
- lines internal surfaces of cavities within bones
13
Q
How do bones grow?
A
- bone can only be laid down onto a surface
- bone cells do not divide (?)
- interstitial growth
- growth plate continues to grow and bone replaces cartilage
- eventually diaphysis and epiphysis fuse together
14
Q
Name the classifications of shapes of bones
A
- long bones
- short bones
- flat bones
- irregular bones
- sesamoid bones
15
Q
Long bones
A
- longer than they are wide
- long diaphysis
- ones of the limbs e.g. femur
16
Q
Short bones
A
- width and length are similar
- involved in movement
- e.g. bones of the wrist and ankle
17
Q
Flat bones
A
- thin, flat, usually curved
- protective in function
- e.g. skull, sternum, scapula and ribs
18
Q
Irregular bones
A
- don’t fit in other categories
- e.g. vertebrae, facial bones
19
Q
Sesamoid bones
A
- small round bones embedded in tendons
- function is to protect tendon and increase range of movement
- e.g. patella
20
Q
What is the composition of the bone?
A
- 30% organic - type I collagen
- 70% inorganic - calcium and phosphate salts
- this provides both tensile and compressive strength
21
Q
Discuss spongy/cancellous bone
A
- found within the epiphyses
- formed from struts of bone called trabeculae that make it look like honeycomb
- red bone marrow would be found in the spaces between trabeculae
22
Q
How may bones are in the human skeleton?
A
- around 206
- 270 in newborns as parts are developing separately and will later few
- number of bones can vary between individuals and vary with age
23
Q
How are bones connect?
A
By joints:
- fibrous (e.g. sutures in bones of skull) - cartilaginous (e.g. IVDs) - synovial/true joints have a gap between bone surfaces due to lubricating synovial fluid, greater range of movement (e.g. humerus)
24
Q
How is the skeleton organised?
A
- Axial skeleton (skull, vertebral column, ribs and sternum)
- Appendicular skeleton (upper limb - pectoral girdle, bones of arms and hands) (lower limb - pelvic girdle, bones of legs and feet)
25
Q
Discuss the skull
A
- most complex area of the skeleton
- houses brain and special sense organs so has a protective function
- viscerocranium (facial skeleton) has 14 bones
- neurocranium (surrounding brain) has 8 bones
26
Q
Discuss the vertebral column
A
- contains 33 bones
- 7 cervical vertebrae in neck region, small, relatively mobile, more susceptible to dislocation, bifid spinous process
- 12 thoracic vertebrae in region of thorax, articulate with ribs, long processes for muscle attachment
- 5 lumbar towards bottom of spine, increase in weight bearing function of bones so these are bigger, larger body, susceptible to herniated IVDs
- 5 fused bones make the sacrum, vertebrae are fused and articulate with hip bones
- 4 fused bones make coccyx, tailbone, can fracture if landed on
27
Q
Discuss the pectoral girdle
A
- made up of scapula and clavicle
- clavicle is only bone connecting upper limb to axial skeleton
- facilitate movement
28
Q
Discuss the pelvic girdle
A
- 2 hip bones (innominates)
- each hip bone has ilium, ischium, pubis
- provide stability - help to transfer weight to limbs
- protect pelvic organs
- different shape in males and females
29
Q
Discuss the limbs
A
Upper limb:
- humerus (arm) - radius and ulna (forearm) - 8 carpals (wrist) - 5 metacarpals and 14 phalanges (hand)
Lower limb:
- femur (thigh) - tibia and fibula (leg) - 7 tarsals (ankle) - 5 metatarsals and 14 phalanges (foot)
Also remember sesamoid bone - patella!
30
Q
Name some bone markings
A
- condyle/epicondyle
- crest/line
- facet
- foremen/notch
- fossa
- process/protuberance/spine
- trochanter/tubercle/tuberosity
31
Q
Discuss the sternum and ribs
A
- flat bones
- surround and protect thoracic organs (thoracic cage)
- important role in respiration
- flexibility provided by costal cartilages anteriorly
- sternal angle
32
Q
Discuss the sternum
A
- made up of 3 parts: manubrium, body and xiphoid process
- sternum angle is an important anatomical landmark
- sternum angle is at level of T4/T5 IVD posteriorly
- ## 2nd ribs articulate anteriorly with sternal angle
33
Q
Why do we need to count the ribs?
A
Clinical relevance - auscultation
- depending on what valve/area of the heart we want to listen to will determine which ribs we would position against
