Ortho complications (Dujo) Flashcards
1
Q
Tension side depends on
A
- overlying soft tissue
- fracture
- forces action on bone
*exceptions: big defect
2
Q
Delayed unions
A
- Fracture takes longer to heal than anticipated
- adequate time but incomplete healing
- healing progressing slower rate than expected
- bone should be healed by
- 3-4 months in adults
- 1-2 months in growing animals
3
Q
Delayed unions
biological causes
A
- Poor vascularity
- usually secondary to trauma
- most common biological cause
- presence of infection
- Escessive postoperative activity
- Systemic dz
- Drugs
4
Q
Delayed union
Biological causes
Systemic dz
A
- Examples of systemic dz
- Primary hyperthyroidism
- Hyperadrenocorticism
- Diabetes mellitus
- Renal dz
- Intestinal malabsorption
5
Q
Delayed union
Biological causes
Drugs
A
- Examples of drugs
- corticosteroids
- antineoplastic drugs
- anticonvulsant drugs
6
Q
Inadequate fracture fixation can result in
A
- Instability and motion
- results: prevention of callus maturation and bone healing
7
Q
DX of delayed union
A
- Slightly subjective
- serial rads
- Eval mechanical and biological factors
- fracture margins distinct
- pseudoarthrosis
- sealed marrow cavity
- arrest or regression of healing
8
Q
TX of delayed unions
A
- Autogenous cancelous bone graft
- Vascularized graft or bone forage
- More rigid fixation
- Remove implants in infection
- make sure there is enough healing
9
Q
Nonunion
A
- All healing processes have stopped with bone unhealed
- two main types
- viable
- nonviable
- surgical intervention necessary
- etiology same as delayed union
- plus seequestration
10
Q
Viable
(biologically active)
A
- Hypertrophic
- Slightly hypertrophic
- Oligotrophic
11
Q
Nonviable
(Biologically inactive)
A
- Dystrophic
- Necrotic
- Defect
- Atrophic
12
Q
Intraoperative findings of non-unions
A
- usually combo of
- fibrous tissue
- instability
13
Q
Hypertrophic non unions
A
- abundant hypervascularized callus
- usually seen in unstable fractures
14
Q
mildly hypertrophic nonunions
A
- Inadequate callus
- mild sclerosis of medullary cavity at fracture site
- associated with rotational instability
15
Q
Oligotrophic nonunions
A
- No visible callus
- ends of medullary cavity sealed at fracture site
- rounding of fragment ends
- fibrous tissue and blood vessels between the fragment edges
- still capable of a biologic response
- seen in significant displacement of fracture fragments
16
Q
nonviable nonunions
dystrophic nonunion
A
- dystrophic nonunion
- occur when secondary fragment has healed
- main fragment is healed and devoid of callus
*kind of looks like the oligotrphic non-union
17
Q
Nonviable nonunions
Necrotic nonunion
A
- Seen in highly comminuted fractures in poorly vascularized areas
- Major fragments eventually die without being incorporated in the callus
18
Q
Nonviable nonunions
Defect nonunion
A
- Results from
- loss of fragments at time of injury or
- resorption of fragment
19
Q
Nonviable nonunions
Atrophic nonunion
A
- Atrophic nonunion
- dystrophic, necrotic and defect nonunions can all lead to atrophic nonunions
- characterized by bone resorption and osteoperosis
20
Q
Factors leading to nonunion
A
- Infection
- Inadequate fracture reduction
- soft tissue disruption
- poor surgical decision making
21
Q
DX of nonunions
A
- Serial rads 3-6 weeks apart
- compare for
- periosteal bone formation
- callus formation
- changes in gap width
- blunting of bone fragments
22
Q
Radiographic signs of nonunion
A
- Sclerosis of bone ends at fracture site
- no progression/changes over 3 months
- progressive bowing at fracture site
- bone atrophy
- fracture ends become thinner and reabsorb
- excess callus around fracture site with radioluscent lines in callus
23
Q
TX guidelines nonunion
A
- Consider underling causes
- lack of stability
- lack of blood supply
- debridement of necrotic bone
- open medullary canal
- rigid fixation
- autogenous bone graft
- can add allograft
24
Q
Malunion
A
- Healing of bone in abnormal position
- functional
- nonfunctional
- causes
- inadequate fracture reduction/stabilization
- nonanatomic positioning
- Resulting deformities
- angular
- rotational
- distracted
- over-riding
25
Treatment of malunion
* corrective osteotomy
* realignment
* rigid fixation
* surgery
* imparied limb function
* stenosis of pelvic canal
* jaw malocclusion
* patellar luxation
26
Osteomyelitis
* Hematogenous spread
* spread from adjacent soft tissue infection
* secondary to penetrating wound
* infection associated with contaminated implant
27
Pathophys of osteomyelitis
* Factors
* blood supply
* soft tissue disruption
* tissue necrosis
* Bacteria form biofilm
* adhere to implant
* host defense can't adequately reach bacteria
* antibiotics less effective against biofilms
28
Osteomyelitis
organisms
* staph
* fungal
* blasto
* crypto
* coccidiomycosis
* nocardia
* actinmyces
29
Radiographic findings
Osteomyelitis
* Soft tissue swelling
* irregular periosteal reaction far from fracture line
* long zone of transition
* can resemble a tumor
\*To diagnose do bone core, submit for cultures
30
Sequestrum
* avascular/nonviable bone fragment
* typically has sharp margins
* can impede healing
* can cause disfunction
31
Ivolucrum
* Periosteal reaction around a sequestrum
* membrane around sequestrum
32
Cloaca
* Opening ininvolucrum
* results in drainage
33
External fixaters are really good at
* Preserving the biology
34
Bandage disasters
* Ischemic bandage injuries
* loss of tissue
* excessive skin compression
* tourniquet effect
35
causes bandage disasters
* Inadequate application of the bandage
* Insufficient padding
* Pre-existing vascular injury
* Bandage changes not frequent enough
36
Quadriceps contracture
* young growing dogs
* **femoral fracture**
* excessive fibrous tissue
* rigid and unfixable extension
* secondary to
* quadriceps muscle trauma
* inadequate fixation and instability
* prolonged immobilization
37
Quadriceps contracture
Prevention
* Early fracture treatment
* Rigid fixation
* Early return to function
* Temporary immobilization
38
Minimizing infection
* No reason to use antibiotics more than 24 hours post-op prophylactically
* Use
* cefazolin 30-60 minutes prior to induction
* then every 1.5-3 hours post-op
* Don't be fast and sloppy in sx
* be efficient and plan out sx
39
Minimizing infection
Contaminated surgical site
* debride as much tissue as possible
* irrigate with saline
* obtain intraoperative cultures
* positive cultures don't mean a patient will develop an infection
