Lecture 18: Principles of Equine Fracture Management Flashcards
T or F: horses have to stand immediately after surgery
True
What are complications from fracture repair
- Prolonged recovery- myopathy and neuropathy
- Implant infections and subsequent osteomyelitis
- Support limb laminitis
What are the AO-ASIF principles
- Precise anatomic reconstruction- accurate alignment, perfect reconstruction of joint surfaces, sx approaches that allow visualization
- Stable fixation
- Soft tissue considerations
- Successful internal fixation
What does successful internal fixation mean
Anatomic reconstruction of bones and joint surfaces that allow sharing of loads between reconstructed bone and implants
What are the simple types of fractures
- Splint bone fractures
- MC stress fractures
- Condylar fractures
- Coffin bone fractures
What are major types of fractures
Long bone fractures
1. Radius
2. MC/MT 3
4. Tibia
Where are splint fractures most common
Distal 1/3 of bone
Are forelimbs or hind limbs most commonly affected with splint bone fractures
Forelimbs
What can cause splint bone fractures
External trauma- kick
Split bone fractures from trauma are often open or closed
Open
what wrong
Open splint bone fracture
Fractures of the mid and proximal 1/3 splint bone are complicated by ___, __, and __
Comminution, joint involvement and bone sequestration
Proximal fragments of splint bone fractures must be secured to ___ to prevent excessive motion and subsequent ___
MC/MT 3, subsequent OA
Proximal fragments of ___especially must be secured to MC/MT II because they make up significant portion of articular surface of carpometacarpal joint
MC II
Splint bones can heal without internal fixation but often result in __ which can impinge on ___ necessitating removal
Callous, suspensory ligament
What is dorsal metacarpal disease
Periostitis and stress fracture of dorsal surface of MC3
What this
Dorsal metacarpal disease- stress fracture of dorsal surface of MC3
Who is likely to get dorsal metacarpal disease
Young thoroughbreds in race training
What are signs of dorsal metacarpal disease
Acute onset after intense exercise, dorsal cortex of M3 painful on palpation
Dorsal metacarpal disease is also called
Bucked shins, shin splints
What is the early phase of dorsal metacarpal disease and what do radiographs show
Bucked shins
Painful on palpation, heat, swelling
Rads show subperiosteal callous, endosteal thickening but NO FRACTURE LINE
What is the late phase of dorsal metacarpal disease
Dorsal cortical fracture, typically 60-70% through dorsal cortex
What is this
Late phase of dorsal metacarpal disease—dorsal cortical fracture
What is tx for dorsal metacarpal disease- early phase
Gradually increase stress to dorsal surface of M3, controlled exercise (reduce galloping by 50%), if speed increased, decrease distance, run on softer surface
What is tx for late phase dorsal metacarpal disease- dorsal cortical fracture
Surgery- place unicortical lag screw
What are clinical signs of MC/MT III condylar fractures
Lameness after work/race
Fetlock joint effusion
What wrong
MC/MT 3 condylar fracture
__condylar fractures more common in thoroughbreds
MC III
__condyle is more commonly affected than ___ in MC/MT III condylar fractures
Lateral condyle
Horses with medial or complete displaced MC/MT 3 condylar fractures should be transported in __ or __
Cast or Kimzey splint
Identify the different types of MC/MT III condylar fractures left to right
Left: incomplete- starts at joint surface and goes up cannon bone a little
Complete/nondisplaced: start at joint surface and out to cortex
Complete displaced- through cortex and out
Medial propagating- allow the way up cannon bone
What typically causes coffin bone fractures
Acute trauma- kicking wall
How do you tx non-articular coffin bone fractures
- Shoeing with bar shoe so foot can’t expand
- Unilateral palmar digital neurectomy
What causes a joint luxation
Rupture of collateral ligaments
For joint luxation take ___radiographs
Stressed view
What wrong
joint luxated
T or F: long bone fractures are true emergencies
True
What is first thing you do when arriving to suspected long bone fracture
Sedate horse
T or F: it is a good idea to do a nerve block on long bone fracture patient
False
___should be suspected with acute onset of severe non-weightbearing lameness
Fracture
Long bone fractures have good prognosis with optimal emergency treatment which includes what
- Sedation +/- anesthesia
- Wound management
- Stabilization
- Infection prophylaxis
- Safe and proper transport
What sedatives and analgesics should you give for long bone fracture
- Alpha 2 agonists- xylazine and detomidine
- Butorphanol
What is appropriate wound management for open fracture
- Cover wound with water soluble ointment
- Clip hair around
- Clean skin around wound
- Clean/lavage wound itself
- Cover with sterile dressing and bandage
What is the principle of fracture stabilization
Regional immobilization- immobilize joint proximal and distal
What are the goals of stabilization
- Reduce stress and anxiety
- Assist with weight bearing
- Prevent soft tissue damage
- Prevent complications (closed becoming open, damage to tissue, increased fragment displaced)
What materials are in Robert jones bandage
- Practical/rolled cotton
- Brown gauze (tight)
- Vet wrap or elastic on
What bio mechanical forces need to be opposed when placing splint
- Extensors- abduct limbs
- Suspensory apparatus- applies bending forces at fetlock and we need fetlock straight
- Reciprocal apparatus- fractures at tibia and tarsus can be displaced by flexion of stifle
Splinting is based on the ability to counteract___
Bio mechanical forces imparted on fracture
How should splint be placed for forelimb phalange fracture
Dorsal
How should splint be placed for metacarpal fracture
Palmar and lateral
How should splint be placed with radial fracture
Lateral up to withers
How should splint be placed with humeral fracture
Caudal up to olceranon
How should splint be placed with scapular fracture
None
How should splint be placed with fracture of hind limb phalanges
Plantar
How should splint be placed with metatarsal fracture
Plantar and lateral
How should splint be placed with tibial fracture
Lateral and up to tuber coxae
How should splint be placed with stifle, femur or pelvic fracture
None
Splint was placed like this for fracture of what bone
radius
If there is forelimb fracture how should they be positioned in trailer
Face horse backwards
If there is hindlimb fracture how should horse be positioned in trailer
Forward/normal
Pelvic fractures are more common in who
Foals and yearlings
What is the cause of pelvic fractures in foals and yearlings
Distinct traumatic event
How do you tx pelvic fractures in foals and yearlings
Internal fixation
How do pelvic fractures occur in adults
During intense exercise without obvious trauma
What is tx for pelvic fracture in adults
Conservative treatment- stall rest
What is a major concern with pelvic fractures
Internal iliac artery can be lacerated resulting in severe hemorrhage, shock and death