Final: Little 3- Bones and misc. Flashcards
Forelimb: What view is this? What type of fracture? Which type of horse is this most common?
DP view
Make sure you take tangential view to fully evaluate the joint
Displaced long parasagittal articular fx of distal MC III
(Lateral condylar fracture)
Most common in young racehorses
___ racehorses will get lateral condylar fractures of MCIII >2x more often than MTIII. In ____ racehorses the front and hindlimb are equally affected.
TB
SB
S = same
What is indicated for first aid in a horse with a lateral condylar fracture?
Compression bandage
NSAIDs
Absolute stall rest
+/- Kimzey splint
How are lateral condylar fractures surgically repaired?
Internal fixation with transcortical screws in lag fashion
2 screws accross the fx site 20mm apart
Where should the first screw be placed when repairing a lateral condylar fracture? What landmark do you use?
Closest to the joint surface
To allow for realignment of the articular surface
Epicondylar fossa
Why is arthroscopy used intra-operatively when repairing an articular fracture?
To ensure articular alignment to ensure a successful surgery
What is the most common long bone fracture in the horse?
Diaphyseal fx of MCIII and MTIII (cannon bone)
What is the optimum treatment for a cannon bone fracture (be specific)?
Double plate fixation with plates placed on the tension side of the bone and 90degrees and off-set from each other, spanning the entire length of the bone
What must you do before placing plates on a cannon bone fracture if the fracture is comminuted?
Reduce/ transform the fx into 2 fragments (with lag screws)
Ensure +++ intrafragmentary compression
If we are gaining compression via plates and screws (rather than lag screws) what is the maximum amount of compression you can achieve?
4mm
1mm per screw, 2 screw on either side of the fx
Which type of plate allows for continuity of bending stiffness and improved blood supply under the plate?
LC-DCP
Which type of plate was specifically designed for equine fracture repair?
Locking Compression- 5.5mm LCP
Which plate function transforms tensile forces into compressive forces?
a. Compression
b. Neutralization
c. Tension band
d. Buttressing
c. Tension band
Which plate placement functions to bridge the area of the bone defect and is rarely used in horses?
a. Compression
b. Neutralization
c. Tension band
d. Buttressing
d. Buttressing
What is the difference between a locking and a cortical bone screw?
Locking screw has thread in the head of the screw
What muscle inserts on the olecranon?
Triceps
What term is used to describe the olecranon in young patients?
Apophysis
What are your ddx for a patient with a dropped albow with the carpus in flexion(NWB)?
Ulnar fracture
Radial nerve paralysis
Humeral fracture
Neuro disease (WNV)
In case of an ulnar fracture, a _____ should be placed to keep the carpus in ______. It should be applied to the _____ surface and extend from the _______ to the _______.
In case of an ulnar fracture, a SPLINT should be placed to keep the carpus in EXTENSION . It should be applied to the PALMAR surface and extend from the FETLOCK to the ELBOW.
What is the treatment of choice for an olecranon fracture?
Open reduction and internal fixation - LC-DCP plate on the caudal ulna
Tension-band principle
What is the weight limit for using a tension band technique to repair an olecranon fracture?
250kg
>250kg requires plate
T/F: In adult horses with olecranon fractures, distal screws can be inserted into the caudal cortex of the radius.
True, ensures rigid fixation
<1yo no- still growing
What type of repair of a femoral physeal fracture can be attempted in foals?
Dynamic hip screw (DHS) system
A 3 mo calf has a closed, displaced proximal tibial physeal fracture with a large metaphyseal fragment laterally. What is the treatment of choice?
Thomas Schroeder Splint/Cast
How should you transport a horse with a closed short oblique fracture with marked displacement and over-riding?
In a trailer with dividers (so horse can lead) with the head toward the back of the trailer
Stabilize patient first
How would you splint a radial fracture?
On lateral and palmar aspect
How many pins per fragment do you need if you are using an external fixator?
Two
How are pins placed in a type 2 external fixator?
Laterally to medially
How are pins placed in a type 3 external fixator?
Laterally to medially
AND
Cranially to caudally
(half-pins)
What type of repair is used for communuted phalangeal fractures?
Transfixation pin casting
What can be done to help increase the strength of a pin and plate repair?
Lute the plates
Cement-like substance for pakcing a joint or coating a porous surface
T/F: Stall rest is unsuccessful for femoral fractures.
True
Why does screw and plate loosening occur in ruminants <4 months of age?
Cortical bone is thin and soft
IM pins for open reduction and stack pinning should be placed as ______ as possible without entering the joint. The pins should also be ________ (type of pin).
Distal
Threaded-end
What is the white arrow pointing to? What type of external fixator is this?
Active drain
Type 1
Against which forces to IM pins NOT protect ?
Axial
Compressive
What is the success rate when using double plate application (on the cranial and lateral aspects) to repair a femoral fracture in a foal?
50%
Adults super shitty prognosis
T/F: Contralateral angular limb deformity is a complication of fracture repair in mares.
False, immature animals
T/F: Fractures can heal in the face of infection.
True
Must remove implant before the whole bone gets eaten by the infection
What material are the antibiotic beads that do not dissolve made of?
PMMA
Why do manibular fractures often heal very well?
Excellent vascular supply and non-weightbaring
T/F: Loose teeth should be removed when a mandibular fracture is repaired.
False, NEVER until after the fracture has healed
When using screw and wire fixation to repair a mandibular fracture, which structures must you avoid?
Facial nerve
Buccal branch of facial nerve
Palatine artery
Tooth roots
How would you repair this fracture of the incisive area of the mandible?
Cerclage wire fixation
How would you provide tension across a fracture site on the maxilla?
Bilateral tension band wiring/ wire fixation
How would you repair a bilateral fracture of the horizonal ramus of the mandible in a calf?
Normograde pinning with 2 diverging pins (on down each ramus)
What are indications for mandibular plate application?
Fracture of body and vertical ramus of the mandible
Fracture of caudal aspect of the horizontal ramus
On what surfaces can mandibular plates be applied?
Compression surface- vental, lateral, or ventrolateral
Why is a diet change not indicated after a incisor fracture repair?
Causes upset of GI flora -> Colitis
When are implants from mandibular fracture repairs removed?
6-8 weeks
Rads at 6 weeks
What is the primary reason for graft failure in horses?
Infection
What procedure is performed for a horse with a surgical impaction?
Pelvic flexure enterotomy
In which direction does the right ventral colon usually twist?
Dorsomedial
What is the most distal nerve block performed in the horse?
Palmar digital
What horse shoe is indicated for heel pain?
Shortened toe/ roll the toe
What is the maintenance fluid requirement for horses?
40-60 mL/kg/day
What is the incision site for equine castration?
Scrotal
What is the best way to minimize post-castration swelling?
Exercise
What medication is given post-op to all castrations?
Phenylbutazone
Which vaccine is administered at what intervals to a pregnant mare before parturition?
Pneumabort-K (Herpes virus vax)
Month 3, 7, and 9 of gestation
When placing a cortical screw in lag fashion, the glide hole is this size compared to the screw size.
Same size
What is the best non-surgical treatment for ethmoid hematomas?
Intralesional formalin
Which side of the tooth are dental points on the maxilla?
Buccal
What is the lay term used to describe osteoarthritis of the distal interphalangeal joint?
Low ring bone
What joints are affected by bone spavins?
Tarsometatarsal (TMT)
Distal intertarsal (DIT)
When treating a foal with a valgus deformity, which side is the transphyseal screw placed in?
Medial
What is the preferred gastric ulcer medication in foals?
Ranitidine
Which sedative is not given to horses under 2 weeks of age?
A-2 agonists (xylazine)
