Principles of Large Animal Fracture Fixation Flashcards
what are the causes for large animal fractures?
- trauma induced: huge forces needed, most start at the site of stress concentration
- exercised induced: propagated stress fractures, not as commonly seen
what is the first primary goal when dealing with a horse fracture/
keep from becoming an open fracture: decreases outcome by 50%
what risk of complications do large animals have?
- increased infection risk
- lack of soft tissue and vascular supply in limbs
- concerns with recovery
- necessity for weight bearing and stability immediately after recovery
- SUPPORT LIMB LAMINITIS IS THE MOST COMMON CAUSE OF EUTH IN HORSE FRACTURES
T/F: equine species have a much higher infection rate in open fractures than any other species
true
prognosis of open fractures in horses
- no good options
- cannot delay repair to resolve infection
- cannot have instability and infection together and have a successful case!
describe horse recovery after fracture repair
- needs to be able to walk 1-2 hours post op
- patient compliance: unlikely to protect limb
- large torsional forces associated with ambulation
if you dont have a load sharing limb by what time post op what do you do
need to have weight sharing limb by 6 weeks post op, if not likely will euth
risk of death with horse fractures
4.9% risk of death with fractures with anesthesia
- lower solubility with inhalables so more titratable, can wake up faster
- positioning: myopathies/neuropathies
- monitoring: direct arterial blood pressure
- swimming pool recovery
what is the safest recovery system for a horse
swimming pool
T/F: phalangeal fractures are really common in horses
true
how is a fracture in a large animal different than a small animal?
- fracture types all are the same: transverse, oblique, short oblique, transverse with butterfly
T/F: olecranon fractures are common in horses
true, usually slip and fall fractures
present with dropped elbow
resolve well as long as not articular
does prognosis get worse or better the higher up on the limb you go in a horse?
worse the higher you go
what is the most common cause of horses being euthanized with fractures?
support limb laminitis
how to approach a call of a non-weightbearing horse
- where is horse: field, caught under fence?
- what to do until you get there: sedate/quiet, don’t lead anywhere until splinted, go to horse and don’t let it move
ambulatory truck fracture kit
- sedation
- NSAIDS
- bandaging supplies
- duct tape: best to secure splints from slipping
- PCV splints or fiberglass casting material
- Kimzey leg saver splint : ideal for phalangeal fractures
objectives when approaching a horse with a nonweightbearing limb
- minimize further damage
- prevent closed fractures from becoming open
- prevent further contamination if there are wounds
- assess/stabilize
- radiographs
- prognosis CONSULT
- determine intended goals: athlete vs brood mare, ability to do after care, prognosis
what factors affect fracture prognosis in horses?
- fracture location
- displaced vs non displaced
- close vs open
- degree of soft tissue injuyr
- contamination
- articular surfaces? minimizes athletic capability
- synovial structures
- age, breed, use temperatment
- intact strut of bone between articular surfaces
what should you place the splint over?
a bandage! should never go on skin
objectives of a good splint
- neutralizes damaging forces
- allows horse to ambulate
- doesnt require general anesthesia
- economical
types of splints
- wood
- PCV pipe
- plastic adjustable
- fiberglass
- kimzey
measurements for PVC pipe splints in horses
- 6-8 inches
- at least 1/4 inch wall thickness
- can be bent with propane torch
- cut into thirds with rasped edge
- multiple lengths
what splint is best for phalangeal fractures?
kimzey splint
aluminum, different sizes, investment good
if you are using a fiberglass casting material, what structure does it need to include?
the foot!
what are the 4 zones for fracture stabilization in horses?
zone 1: phalangeal
zone 2: cannon bone
zone 3: radius/tibia
zone 4: above elbow/stifle
what splint do you use for zone 1 fractures?
dorsal splint in forelimb
plantar splint in hindlimb
what splint do you use for zone 2 fractures?
robert jones bandage and then caudal/plantar and lateral splint
in forelimb: caudal splint to lock carpus in extension
what splint do you use for zone 3 fractures?
robert jones bandage with extended lateral splints
what splint do you use for zone 4 fractures?
cannot immobilize elbow/stifle, so cant use splint
EXCEPTION IS FOR OLECRANON FRACTURES
HOW DO YOU SPLINT AN OLECRANON FRACTURE !!!!!**
caudal splint extending from point of elbow to the fetlock: this is the ONE INSTANCE where there’s no benefit to extending the splint to the ground
what is the one exception where there’s no benefit to extending the splint to the ground?***
olecranon fractures!!! caudal splint extending from point of elbow to the fetlock
emergency first aid management of horse fractures include
- sedation
- initial wound management
- fracture stabilization
- analgesia and antiinflammatories
- abx prophylaxis
- IVF
- careful safe transportation
what medications can be used for analgesia and anti-inflammatoy needs in horse fractures?
- NSAID: ex phenylbutazone
- opioids: ex butorphanol
- caudal epidural: morphine, detomidine
when are abx indicated in horse fractures?
open wounds or fracture
broad spectrum IV: penicillin, gentamicin
T/F: you don’t put local anesthetics on fractures
true, because you dont want them to take a misstep if they cannot feel their foot
transporation for horse limb fractures
- minimize walking distance
- use ramp with minimal slope and nonslip surface
- transport with lateral support to body wall
- position in trailer: FRACTURE INBACK: hindlimb fracture faces forward, forelimb fracture faces backward
- caution in braking, acceleration and turns
- unload using sound limbs first: turn around
where should the fracture on the horse face when in a trailer?
fracture in the back
forelimb: face backward
hindlimb: face forward
screws used in horse fractures
4.5 and 5.5 cortical screws
cortical screws are placed in what fashion in horses
- lag fashion
- reduce shear forces
- weak compared to plate fixation when high torsional, bending or compressive forces
when is external fixation indicated in horses?
- comminuted phalangeal fractures
- MCIII/MTIII
- breakdown injury to fetlock
