Fracture Disease And Complicaitons Flashcards
What are complications of fracture immobilization?
Quadriceps contracture Disuse osteoporosis Muscle atrophy Ligamentous laxity Cartilage atrophy Fracture associated sarcoma
Most common complication after distal femor fractures that are improperly immobilized>
Quadraceps contracture
Predisposing factors to quadriceps contracture?
Young patient <6months
Poor use of limb during healing
Immobilization of limb
Extensive muscle trauma
Clinical presentation of quadriceps contracture?
Muscle replaced by fribrotic tissue
Forms adhesions between muscle and bone
Tight band at quadriceps Difficulty ambulatory Muscle atrophy Hock/stifle locked in extension Toe excoriation
Dorsally raised patella
Radiographs show..
patella drawn proximally
Genu recurvatum
Ankylosis and DJD
Quadripceps contracture
Genu recurvatumm = knee bent backwards
How do you prevent quadriceps contracture?
Early return to function Physical therapy No immobilization Ice packs NSAIDS
Treatment of quadriceps contracture?
Salvage
-release of quadriceps
Arthrodesis (last ditch)
Amputation (toes abraded)
Dynamic flexor brace
Prognosis
- poor for full fxn
- guarded for partial fxn
What do you call loss of bone due to reduction of mechanical stress?
Disuse/secondary osteoporosis
Wolfs law - osteoclasts
If disuse osteoporosis is longer than ______ the damage can be permanent
12 weeks
If you have muscle atrophy due to immobilization after fracture, how much longer does recovery take?
2-4x longer
How is ligamentous laxity resolved?
Improved muscle tone
How does cartilage atrophy occur?
Joint use stimulates glycosaminoglycans
Immobilization decreased GAG —> cartilage erosion and ankylosis
Cartilage atrophy is reversible if under ____ weeks
4
Can be permanent over 7weeks
Digital flexor contracture is seen following what cases?
Small dogs with fracture of elbow/antebractum
Walks on 3 legs with carpus flexed
Prevention and treatment of digital flexor contracture?
Encourage limb use
Spoon splint
Passive range of motion
Fracture assoicated sarcoma is seen in what breeds more commonaly
Large
Fracture associated sarcoma is usually seen with what type of fracture?
Comminuted femoral fracture
etiologies of fracture assoicated sarcoma?
Implant corrosion at fracture site
- Jonas pin
- TPO plate
Dissimilar metals
Complicaitons( inflammation or infection)
What do you call a slower than expected healing
Delayed union fracture
What do you call a fracture that the progression of healing has ceased?
Non union fractures
What are the two types of non union fractures?
Viable — abundant callus formation (elephant foot)
Non viable — lack blood supply
T/F: non union fractures are unlikely to heal without some form of intervention
True
What are mechanical factors that can cause non union fracture/ delayed union?
Fracture segment proximity — avoid gaps larger than bone diameter
Motion at fracture site
- some motion can trigger stem cell proliferation
- too much motion damages cells and prevents callus formation
What factors can alter the biological environment affecting bone healing?
Decreased blood supply of periosteum
Decreased surrounding soft tissue
Increased age
Open reduction/fixation method (extrinsic factors)
What cells are found in the periosteum and medullary cavity, decrease in aging patients and will proliferate when exposed to growth factors ?
Cellular environment
Causes of delayed and non union fractures?
Fracture instability
Damage to vascular supply
Bone affected
- radius and ulna (blood)
- femur (most commonly broken)
- humerus
- tibia
Local infection
Large fracture gaps
Fixation
Metabolic conditions
How does local infection alter bone healing?
Alter pH and release enzyme that prevent neovascularization
What metabolic conditions can impair bone healing?
Renal disease
Cushings
Hypothyroid
glucocorticoids
What is the treatment for delayed union fractures?
Additional time to heal
Replace or add implant if failure
Infection - culture and treat
Reduce patient activity
If you have treated a delayed union fracture and it has no improvement in 2-4weeks, it is then what kind of fracture?
Non union
Treatment of non-infected viable non union fractures
Fracture stabilization
Bone graft
External fixator to preserve blood supply
How do you treat a non infected, non viable, non union fracture?
Stabilized
Removed fibrous tissue from fracture site
Removed loose implants
Ream medullary cavity to reestablish blood supply
Bone graft
Roger bone ends until bleeding
How do you manage open fractures?
Manage patient first
Limb viability?
Debridement
- sterile lube over wound
- cover wound
- clip hair
- clean surrounding with 4%CGS
- debride non viable tissue
Vigorous irritation of would
-7-8psi sterile saline of 0.05% Chlorhexidine
Cover with sterile dressing
Stable bandage
T/F: antibiotics are always indicated for open fractures
True
What antibiotics do you give in case of open fractures?
Culture
Combo of gram pos and neg, anaerobic, aerobic
Most effective if <3 hours from injury
Change based on culture results
Cephalosporins and fluroroquinolones
T/F: fractures can heal with coexisting infection
True
But they will not heal is there is also instability
Why do most open fractures have increased healing times?
More necrotic tissue
Disruption of blood supply
Cancellous atuografts are indicated
What is the best open fracture stabilization method that allows bone access to the wound and doesnt spread contamination ?
External fixator
Bone plate
Etiologies of osteomyelitis?
Open fracture repair
Hematogenous
Most common causative organisms of osteomyelitis ?
Staphylococcus intermedius
E.coli
Pseudomonas
Pathophysiology of osteomyelitis?
Damage to bone
Vascular compromise and ischemia
Bacterial contamination
Necrotic tissue, instability
Lack of blood supply—> perpetuate infection
Surgical implants
- biofilm, adherence, colonization
- antimicrobal resistance
Clinical signs of osteomyelitis ?
Excessive local pain
Excessive swelling
Fever
Lethargy
Osteomyelitis appears how on radiographs?
Loose or broken implant
Lucency around implant
Periosteal proliferation
Sequestrum
Can confirm with biopsy and culture
How do you manage osteomyelitis ?
If fracture healed - remove implant and give long term antibiotics
Not healed but implant is stable— leave in
Fracture not healed and not stable e— replace with stable fixation method
Large amount of discharge —> treat as open wound, direct culture Debride and lavage Pack IV abs for 3-5days then oral for 6-8wks When discharge stops, close or heal by second intention
How do you manage a sequestrum ?
Dead bone from osteomyelitis
Involcrum — bone formed around sequestrum
Use rongeurs or bur to remove
Treat infection
If weakens bone — provide stabilization
