External Fixation Flashcards
what is the ultimate goal of fracture treatment? (x2)
- early ambulation
- complete return of function
what are the 4 principles of fracture treatment, according to the AO group?
- anatomic reduction of fragments
- stable fixation (suitable to biomechanics)
- preservation of blood supply to fragments/soft tissue
- early, active pain-free mobilization of muscles and joints adjacent to the fracture
what are the objectives of fixation?
- stabilize fragments
- prevent displacement, angulation, rotation
ideally, fixation should permit the use of as many joints as possible during healing period
what does “fracture disease” mean?
phrase used to describe complications associated with fracture treatment and immobilization, such as:
* bone atrophy
* soft tissue atrophy
* nail, skin, cartilage atrophy
what is the most devastating form of fracture disease in dogs?
quadriceps muscle contracture associated with femoral fractures (young animals)
what are the 3 categories of fixation methods?
- splinting limb
- splinting bone
- compression of bone fragments
true or false: there is a certain amount of motion at the fracture site because of the inherent flexibility of devices like casts and splints.
true – and the surgeon must ensure this motion is still within limits to allow for healing callus to form
which devices are considered “coaptation fixation devices”?
external casts, splints, and bandages
how do bandages help in wound management?
bandages can:
* provide limb compression in early post-op period
* cover wounds with absorbent material
* provide support to limbs
* stretch joints
how do casts and splints differ from bandages as external coaptators/
these materials provide rigidity and may protect surgical repairs or provide support for soft tissue injuries
what is “bivalving” a cast?
it means that the cast is cut in half (cranial/caudal or medial/lateral)
doing this allows to easily inspect tissues under it and redressing without having to form another cast
what is the advantage of a moulded cast/splint compared to a commercial pre-made one?
custom fit = cause fewer soft tissue problems and are better tolerated by the patient
what is the most fundamental role of coaptation?
decrease joint motion
advantages of external coaptation:
- minimal disruption of fracture environment
- no implants at fracture site
- decreased risk of infection
do we use external coaptation in short or long term?
can be both!
short term: decrease motion of bone fragments before fracture repair
long term: decrease bone fragment motion in patients with fractures that can be managed without surgery
note that external coaptation does not neutralize all forces that may act on a fracture
what are 4 disadvantages of coaptation?
- cost of materials and labour
- decrease limb use in early post-op period (may lead to long term limb disuse)
- decrease joint motion (may promote long-term loss of motion and prolonged stiffness)
- tissue complications secondary to bandages (redness, chafing, bruising, ischemic injuries, lact of bone healing)
when do we use temporary splinting?
if there will be a delay in reduction and fixation a temporary splint of the limb should be used to reduce additional trauma and pain
especially true for:
- fractures distal to elbow/stifle
- any limb fracture where animal needs to be transported and there is risk for closed fracture to open
when do we use long-term splinting?
- closed fracture below elbow or stifle
- fractures amenable to closed reduction (without opening skin/soft tissues)
- fractures where bone will be stable after reduction relative to shortening or distraction
- fractures where bone can be expected to heal quickly so that cast/splint won’t cause fracture disease
what 3 fractures is casting suitable for?
- greenstick fractures
- long-bone fractures in young animals (periosteal sleeve intact)
- impaction fractures
all must be DISTAL to stifle or elbow
where should a splint or cast immobilize the joint to be effective?
ABOVE AND BELOW the fracture
what are 5 factors to consider when using a splint or cast?
- padding – light for soft tissues, pad valleys not mountains, shielding pressure points
- fixation – anchor cast/splint to avoid shifting on limb, mould cast to countour of limb
- radiographs – check reduction before and after a few days
- extent – expose tips of centre two toes to evaluate swelling
- tolerance – check if patient is in pain, lameness gets worse, high temp, swelling, numbness, odor, chewing cast and REMOVE IMMEDIATELY if so
what should i tell the owner about home care for external coaptation?
- observe toenails for swelling twice/day
- controlled short leash walks with protective covering
- remove wet bandages immediately
- routine bandage checks
- immediate check up if patient is bothered, smell present, worsening lameness, shifting or unstable bandage
what is external skeletal fixation, or “ex-fix”?
a surgical method whereby fractures, luxations, or injuries involving ligaments or tendons are stabilized using a device where the majority of the fixation remains outside the skin surface
what are 5 reasons to use an ex-fix?
- can be placed with minimal damage to local blood supply and disruption of fracture hematoma
- secondary healing achieved may be faster than primary with more invasive approaches
- with compromised biology this allows for adequate fixation & access to soft tissues
- frame is adjustable
- when used as the only repair, all implants can be removed
