Skeletal Activities - Bone fracture, Healing, and Treatment Flashcards
bone grows in length via __________ and in width via __________
- endochondral ossification
- appositional growth
7 stages in initial bone development through endochondral ossification
- hyaline cartilage model
- calcification of cartilage
- primary ossification center formation
- medullary cavity development
- secondary ossification centers formation
- formation of compact bone
- mature bone
______ and ______ cartilage growth causes the cartilage model to lengthen and broaden
- interstitial
- appositional
Does a medullary cavity occur in a secondary ossification center?
No
During fetal bone development, cartilage is entirely replaced by bone except for __________ and __________
- epiphyseal growth plate
- articular cartilage
In mature bone the only cartilage remaining is where?
on the articular suraces
_________ spongiosa is made up of immature trabeculae
primary
_________ spongiosa is made up of mature trabeculae
secondary
________: the sculpting process that follows the elongation of growth. process by which the overall shape is changed in response to physiologic and/or mechanical influence
bone modeling
during bone modeling, bone formation occurs at the ________ surface and bone resorption occurs at the ________ surface
- periosteal surface
- endosteal surface
________: wherein old bone is resorbed by osteoclasts and replaced by new bone at the same surface
bone remodeling
(bone modeling/bone remodeling) does NOT result in a change in the shape or position of bone
bone remodeling
3 things that can shift the balance between bone formation and resorption
- drugs
- hormones
- mechanical forces
What does BRU stand for?
Bone Remodeling Unit
4 stages a BRU goes through
- resorption
- reversal
- formation
- resting
_____: BRU stage where osteoclasts break down mineralized matrix, creating an erosion cavity
resorption
_____: BRU stage where mononuclear cells prepare bone surface for new osteoblasts that will form bone
reversal
_____: BRU stage where osteoblasts synthesize osteoid, which is then mineralized
formation
_____: the BRU holding stage between remodeling cycles
resting
_______ is a condition where bone resorption outweighs bone formation, commonly seen in human females following menopause
osteoporosis
bone adapts to loading by modifying its ________ and/or ____________
- mass
- architecture
_______: a break in the continuity of bone
fracture
5 areas of fracture classification
- etiology
- displacement
- relation to the external environment
- pattern
- location
3 etiological categories of fractures
- traumatic
- pathologic fracture
- stress fracture
2 displacement categories for a fracture
- undisplaced
- displaced
2 categories for a fracture’s relation to the external environment
- simple/closed
- compound/open
8 types of fracture patterns
- transverse
- oblique
- spiral
- comminuated
- avulsion
- impacted
- fissure
- greenstick
3 categories of fracture location
- growth plate
- trabecular bone
cortical bone
3 signs of fracture
- lameness
- pain
- swelling
Fracture treatment can depend on what 5 factors?
- type of fracture
- age
- health
- owner’s finances
- surgeon’s technical expertise
6 factors that impair bone fracture healing
- advanced age
- poor nutritional status
- inadequate blood supply
- soft tissue between fractured ends of bone
- inadequate immobilization
- infection at frature site
4 arterial blood supplies to long bones
- nutrient artery (marrow cavity)
- metaphyseal artery
- epiphyseal artery
- periosteal artery
at heavy periosteal attachments, the outer 1/3 is supplied by branches of periosteal arteries (________) and the inner 2/3 is supplied by branches of the nutrient artery (________)
- centripetal flow
- centrifugal flow
at sites of loose periosteal attachment, nearly the entire cortex is supplied by _________ flow from the _____________
- centrifugal flow
- nutrient artery
centripetal flow to the cortical bone is supplied by the ______ arteries
periosteal
centrifugal flow to the cortical bone is supplied by the _______ arteries
branches of the nutrient artery
2 types of bone healing
- direct (primary) bone healing
- indirect (secondary) bone healing
__________ bone healing accounts for 1 % of clinical cases and _________ bone healing accounts for the other 99%
- direct
- indirect
Which type of bone healing does not require callus formation?
direct bone healing
_______ bone healing only occurs under conditions of absolute fracture stability
direct
_______ bone healing occurs via direct osteonal remodeling
direct
________ bone healing occurs when fixation and stabilization are inadequate for direct osteonal remodeling
indirect
_______ bone healing requires the formation of a fibrous/cartilaginous callus to proceed
indirect
_________ occurs in areas of cortical bone by the energy of the trauma itself
necrotic bone
necrotic bone removal is accomplished by _____
osteoclasts
________: the unit that re-establishes the Haversian structure of the cortex during direct bone healing
cutter cone
the 2 components of the cutter cone
- osteoclasts at the tip of a capillary bud that crosses the fracture site
- behind the osteoclasts, a cuff of osteoblasts lays down concentric lamellae of bone (osteons)
4 stages of indirect (secondary) bone healing
- inflammation
- soft callus
- hard callus
- remodeling
hematoma formation occurs during the _______ stage of indirect bone healing
inflammation
the repair stage of indirect bone healing includes the formation of the ________ and _________
- soft callus
- hard callus
In a fracture, the periosteum will be torn where?
Opposite the point of impact
2 key components to management of bone fractures
- fixation
- stabilization
_____: apposition of bone fragments
apposition
______: preventing the movement of bone fragments
stabilization
2 types of fracture nonunions
- vascular
- avascular (atrophic)
______: type of nonunion in which a callus forms but the fracture fails to heal
vascular
_______: type of nonunion where a bone callus fails to form
avascular (atrophic)
which type of nonunion has a better chance at recovery?
vascular
6 methods of stimulating bone fracture healing
- implantation of cancellous bone autograft
- percutaneous injection of bone marrow cells
- implantation of bone graft substitute
- bone morphogenic protein (BMP)
- electrical or ultrasound stimulation
- shock wave treatment
What is the most commonly used method of bone fracture stimulation used by veterinary orthopods?
implantation of cancellous bone autograft
