12. fracture complication Flashcards
delayed
delayed will heal, just not healing at the rate its expected to
delayed non-union doesn’t mean its going to become non-union
factors that can lead to delayed and non-unions
-inadequate stability
-inadequate reduction
-infection
-loss/poor blood supply
-systemic factors (endocrine)
-idiopathic
non-union
non-union- can heal but WONT without intervening
failure of progression seen in rads for at least 3 months
what are the blood supply sources of the bone
periosteum
nutrient artery
soft tissue
where do bones get their blood supply after a fracture
extraosseous- from surrounding tissues
medullary supply eventually takes over once It heals
weber-cech classsification
viable vs nonviable
viable-vascular,reactive
-variable degrees of proliferation bone reaction/activity
non-viable, avascular, non-reactive
-more difficult to achieve union
viable hypertrophic non-union
there is a large callus
some bone activity
“elephant foot”
abundant callus that isn’t able to bridge to fracture gap
cause: too much movement, inadequate stabilization
strain is NOT <2% so bone isn’t able to fully heal
moderately hypertrophic non-union
moderate size callus that hasnt bridged the fracture
“horse foot”
less callus than viable hypertrophic nonunion
cause: inadequate stabilization and excess movement
strain >2% - not good for bone healing
oligotrophic non-union
minimal to no callus present
fibrous and vessels in the fracture
hard to differentiate from non-viable
viability not obvious through rads
cause: excess movement, inadequate stabilization BUT ALSO decrease/loss of cellular activity
loose implants in the area of the fracture
FB(broken implant) +movement
non-viable dystrophic non-union
one or both sides of the fracture ends are nonviable(avascular)
fracture heals to one side and not the other
common in radius/ulna fractures in toy breeds
non-viable necrotic non-union
sequestrum in site
nonvascularized bone fragments- no blood supply and cant heal to the main fragments
there no activity-no osteoclast activity either
non-viable defect non-union
the fracture gap is to large for biological activity
cant bridge the fracture together due to distance
gap >1.5 x the diameter of the bone
comminuted/high trauma fractures
non-viable atrophic non-union
this is the end result of the other non-viable non-union (didn’t intervene to prevent this)
resorptive and rounding of edges-disuse osteoporosis
define clinical consequences of delayed and non-unions in patients
deformed legs/bowing
shorten legs
degenerative joint disease-arthritis
muscle atrophy from disuse-also osteoporosis from disuse
never using the leg- may amputate
gait abnormalities
what are the clinical signs of delayed/non-union
painful
not formed a callus-movement/ instability felt at the fracture
lameness
disuse atrophy of the limb
treatment of delayed/malunion
treat infection
minimize fracture gap-improve reduction and apposition
rigid stabilization
improve blood supply
bone graft
animal metabolically unhealthy
- improve stability-apply rigid fixation
- treat infection- C&S
- cancellous bone graft
malunion
fracture heals in an abnormal anatomic position
alignment
look at the joint below and above- must have a the same lateral/medial etc view
apposition
look at the fracture- how well are those pieces aligned
this varies depending on the fracture and repair- biological fixation or anatomic repair
apparatus
implants used
activity
bone activity - is it forming a callus? is it bridging the gap
this is assessed at the recheck rads- not immediately after surgery
define the benefits of assessing fracture repair and fracture healing
improve your own techniques/learn from it-surgeon growth
predict the progress of the fracture- whether you expect a callus formation of not, etc
quality of the rads
2 orthogonal views
joints above and below
perfect apposition =
excellent alignment
direct or primary bone healing
<1mm
direct contact healing
no callus
cutting cones
decrease opacity
indirect healing/secondary
initial resorption of fracture ends
radiolucency at fragment ends- increase fracture gap
10-14 days periosteal and endosteal callus visible
