Fracture Objectives Flashcards
What are the 4 A’s of radiographic fracture evaluation?
Apposition
Alignment
Apparatus
Activity
What radiographic change indicates implant loosening?
Lucency around pin or screw
What are the 2 types of non-union fractures?
Viable and non- viable
What are the differences between viable and non-viable
non-union fractures?
Viable: fibrous tissue between fracture ends
Non-viable: fracture ends are sclerotic
What is the treatment for non-union fractures?
surgery to remove fibrous/sclerotic ends
What is the pathogenesis of quadriceps contracture?
muscle fibers replaces by fibrous tissue→
adhesions between muscle and bone→
severe decreased limb mobility
What are the risk factors for quadriceps contracture?
Distal femoral fracture
Young (<6 months)
Prolonged immobilization in non weight-bearing position
Extensive muscle or soft tissue trauma
What treatment options are available for quadriceps contracture?
Treatment rarely successful but options include:
Z-plasty of quadriceps muscles
Stifle arthrodesis
Limb amputation
What is the prognosis for quadriceps contracture?
Poor for full function
Guarded for partial function
What conditions are associated with overly rigid fixation or immobilization?
Joint stiffness
Muscle contracture
Disuse osteoporosis
Ligamentous laxity
What radiographic changes are seen with aggressive neoplastic
bone lesions?
cortical lysis
periosteal rxn
mineralization of soft tissues
loss of trabecular pattern
lack of distinct border
What differentials are associated with the following radiographic changes?
cortical lysis
periosteal rxn
mineralization of soft tissues
loss of trabecular pattern
lack of distinct border
Osteomyelitis
Osteosarcoma
Chondrosarcoma
Fibrosarcoma
Hemangiosarcoma
Lymphoma
Bone Cyst
What treatment for Osteosarcoma has the longest MST?
Amputation + Chemotherapy
(MST = 9 - 12 months)
What is the purpose of amputation in osteosarcoma if there is
no effect on survival time?
High complication rates if trying to spare limb:
infection
implant failure
local reccurrence
What are the most common sites for metastatic lesions of Osteosarcoma?
Lungs
Other bones
Lymph nodes
What staging is recommended for Osteosarcoma?
Thoracic CT
LN aspiration
CBC/Chem/UA
What is the GOLD STANDARD for diagnosis of bone lesions?
BIOPSY!
What bone tumor locations are amenable to limb sparing tx?
Distal radial bone lesions
Other than osteosarcoma, what primary bone tumors are diagnosed
in small animals?
Chondrosarcoma (CSA)
Fibrosarcoma (FSA)
Hemangiosarcoma (HAS)
What bone tumors are specific to the digits?
Dogs: SCC, Melanoma
Cats: SCC, FSA, Adenocarcinoma, OSA, HAS
What nerve needs to be avoided in internal fixation of scapular
neck fractures?
Suprascapular nerve
What type of bone plate is used for unstable
scapular body fractures?
Locking plates
What condition seen most commonly in spaniel breeds predisposes them to humeral condylar fractures?
IOHC
(Incomplete Ossification of Humeral Condyle)
Which aspect of the humeral condyle fractures most often and why?
Lateral aspect because of:
Increased weight bearing and
Smaller epicondylar crest
How is a lateral or medial humeral condylar fracture repaired?
How about a T or Y fracture?
Lateral or Medial: Lag screw + anti-rotational wire
T or Y: Plate application
Why are distal radius/ulna fractures in small breed dogs more likely to experience healing complications?
Inherently unstable fractures
Poor blood supply to bone
Minimal soft tissue coverage
Limited intraosseous circulation
Under what conditions should metacarpal or metatarsal fractures be surgically stabilized?
All 4 MC bones are fractured
More than one MC is fractured and there is severe displacement
MCs 3 and 4 are fractured
What other injuries might one expect to see in a patient with pelvic fractures?
Pelvic fractures are usually caused by trauma, so usually see more
than one fracture and other HBC injuries like diaphragmatic hernia, etc.
Why is a thorough neurologic evaluation so important in pelvic fracture cases?
Need to assess:
Pelvic limb function
Anal tone and sensation
Urinary continence (LMN)
Tail sensation
Gives info about location of injuries and how to treat
Surgical stabilization of pelvic fractures should always be recommended in certain cases. What are these fracture types or clinical scenarios?
Cranial acetabulum fracture
Ilium fracture
Sacroiliac luxations
Hip instability
(weight bearing functions)
When is conservative management recommended for pelvic fractures?
Stable, minimally displaced fractures
Fractures that do not disrupt continuity of pelvic canal
Fractures that do not affect weight bearing
What are the risks associated with conservative management of pelvic fractures in which surgical repair is recommended?
Malunion with pelvic canal narrowing→ constipation, dystocia
Entrapment of sciatic nerve in callus
Non-union
Why is deep pain sensation necessary to assess when evaluating a patient with spinal trauma?
If no deep pain, must euthanize
What are the 2 main goals of surgical repair of spinal fractures/luxations?
Decompression of spinal cord
Stabilization of vertebral column
What are the benefits of CT vs MRI with regards to imaging of the spine and providing information to help achieve these surgical goals for
spinal fractures/luxations?
CT is best modality for bony lesion detection
MRI is best for assessment of spinal cord and changes within the canal
Most sensitive method for overall evaluation is BOTH CT and MRI!
When is it appropriate to recommend conservative management of a spinal fracture?
If animal is ambulatory, fracture is stable, and there is no neuronal deterioration
(or if there is intact nociception, but the owner is not willing or able to pay)
Name the condition that can occur when a young animal’s comminuted
femoral fracture is treated with rigid immobilization for an extended period of time
Quadriceps contraction
Of the 4 A’s that are evaluated in post-op fracture repair rads,
which term relates to the positioning of joints?
Alignment
What Abx is the best first choice for tx of an open fracture?
Cefazolin
What specific lesion can be seen with chronic osteomyelitis?
Sequestrum
What is the average healing time for fractures?
6 - 8 weeks
T/F:
Quadriceps contracture is usually reversible
FALSE! usually irreversible
How is Quadriceps contracture prevented?
In distal femoral fractures, only use
internal or external fixation
(NEVER use coaptation for femoral fractures!)
ROM exercises and NSAIDs
immediately to prevent mm. atrophy and scarring
What animals are predisposed to osteosarcoma?
Large and Giant breed dogs
Either 18-24 months old or around 7 years old (bimodal age distribution)
What are the predilection sites for osteosarcoma?
AWAY from Elbow, TOWARDS the Knee
- Proximal humerus
- Distal radius or ulna
- Proximal tibia
- Distal femur
What CBC/Chem/UA change is associated with poorer prognosis
in cases of osteosarcoma?
Increased ALKP
What are biphosphonates and how are they used in the treatment
of osteosarcoma?
Biphosphonates can be used for PALLIATIVE tx of OSA
They are osteoclast inhibitors which decrease rate of lysis and improve pain scores
______% of skeletal tumors in canines are Osteosarcomas
85%
What type of scapular fracture can be treated conservatively?
STABLE extra-articular fractures
How is a glenoid tubercle (attachment of the biceps brachii) avulsion
treated?
Lag screw or
Pin and tension band
Fracture of the ulna with dislocation of the radial head
is known as this type of fracture
Monteggia Fracture
Type 1 most common
What is the recommended treatment for ALL
complete distal radius/ulna fractures in small breed dogs?
SURGERY! Not external coaptation!!
What are the most common sites for spinal fractures and luxations?
T3 - L3
and
L4 - L7
What 2 types of salter harris fractures might go
undiagnosed on initial rads?
Type 1 or Type 5 (go across physis)
