introduction to bone and soft tissue

Question 1

what makes up the musculoskeletal system?

Answer 1

bone
muscle
connective tissue- tendon, ligaments and cartilage

Question 2

how many bones does the adult human skeleton have?

Answer 2

206

Question 3

how many bones do children have?

Answer 3

270

Question 4

what is in the appendicular skeleton?

Answer 4

pectoral girdle
upper and lower limbs
pelvic girdle

Question 5

what is in the axial skeleton?

Answer 5

cranium
vertebral column
rib cage

Question 6

what are the 5 functions of the skeleton?

Answer 6

support
protection
movement
mineral storage
haematopoiesis

Question 7

what are 2 components of bones?

Answer 7

cells

matrix

Question 8

what are the bone cells?

Answer 8

osteogenic cell
osteoblast
osteoclast
osteocyte

Question 9

what is the osteogenic cell?

Answer 9

stem cell

Question 10

what is the osteoblast?

Answer 10

bone forming
secretes osteoid
catalyse mineralisation of osteoid

Question 11

what is the osteocyte?

Answer 11

mature bone cell
formed when osteoblast imbedded in its secretions
sense mechanical strain to direct osteoclast and osteoblast activity

Question 12

what is the osteoclast?

Answer 12

bone breaking
dissolve and resorb bone by phagocytosis
derived from bone marrow

Question 13

where are osteogenic cells found?

Answer 13

deep layers of periosteum

Question 14

where are osteoblasts found?

Answer 14

growing portions of bone including periosteum and endosteum

Question 15

where are osteocytes found?

Answer 15

entrapped in matrix

Question 16

where are osteoclasts found?

Answer 16

bone surfaces and at sites of old, injured or unneeded bone

Question 17

how is the bone matrix split up?

Answer 17

organic(40%)(type 1 collagen and ground substance) and inorganic(60%)(calcium hydroxyapatite and osteocalcium phosphate) components

Question 18

what makes up ground substance?

Answer 18

proteoglycans
glycoproteins
cytokine growth factors

Question 19

what is an immature bone?

Answer 19

first bone that is produced
laid down in a woven manner- relatively weak
mineralized and replaced by mature bone

Question 20

what is mature bone?

Answer 20

mineralized woven bone

lamellar (layer) structure- relatively strong

Question 21

what are the 2 types of mature bone?

Answer 21

cortical

cancellous

Question 22

what are the features of cortical bone?

Answer 22

compact- dense

suitable for weight bearing

Question 23

what are the features of cancellous bone?

Answer 23

spongy- honeycomb structure

not suitable for weight bearing

Question 24

what are osteons?

Answer 24

units of bone in compact bone
few spaces
provides protection, support and resists stresses produced by weight of movement

Question 25

what is a Haversian canal?

Answer 25

contains blood vessels, nerves and lymphatics | lies in the centre of an osteon

Question 26

what are lacunae?

Answer 26

small spaces containing osteocytes | tiny canaliculi radiate from lacunae filled with extracellular fluid

Question 27

what is Volkmann's canal?

Answer 27

transverse perforating canals

Question 28

what are the 4 sections of a long bone?

Answer 28

epiphysis physis metaphysis diaphysis

Question 29

what are the 2 types of bone growth?

Answer 29

interstitial- increased length | appositional- increase in thickness and diameter

Question 30

what are the types of joints?

Answer 30

fibrous cartilaginous synovial

Question 31

what are the types of synovial joints?

Answer 31

``` pivot hinge saddle plane condyloid ball and socket ```

Question 32

what is the structure of the synovial joint?

Answer 32

``` articular capsule(outer)- keeps bones together structurally synovial membrane(inner)- contains synovial fluid synovial fluid reduces friction ```

Question 33

how are joints stabilised?

Answer 33

bone surface congruity ligaments muscles/tendons

Question 34

what is problem with poor joint stability?

Answer 34

risk of dislocation

Question 35

what is hypermobility caused by?

Answer 35

excess ligament laxity