Smallies External Coaptation (LaFuente) Flashcards
What 4 mechanical force can act on a fx?
- bending
- rotation
- compression/shear
- distraction
Which types of fx are stable? Which are unstable?
> stable - transverse - green sick (buckling) > unstable - oblique - spiral - comminuted - segmental?? - avulsion - compression??
Which forces are neutralised by a cast? Which are not?
- bending
- rotation
> as long as joints above and below are immobilised
> compression/shear difficult to neutralise with a cast
What are distraction forces?
- muscle tension
- poorly neutralised by external coaptation
- eg. olecranon fx, greater trochanter fx
> sling to v weight bearing?
> reduces muscle tension
> reeduces tension force
- When is external coaptation indicated?
- closed
- minimally displaced (20% in contact minimal)
- stable
- pair of bones (ie. tibia and fibula)
- young animals high healing potential
> 50% contact rule
HOw long do fx take to heal in pupppies?
3-4weeks
What are the 5 basic guidelines for coaptation?
- When?
- Reduction
- ALignment
- Standing positino
- Join above and below
- how is reduction carried out? How much reduction is needed?
> heavy sedation/GA
- repeatras to ensure apposiiton remains throughout healing
adequate reduction 50% contact rule
- juveniles tolerate greater displacement without developing non-union cf. older
- aims for aligment? Consequences of malalignement?
- perfect reduction rare
- proper joint alignment must be maintained
- failure to align major bone fragments to joints of limb -> angular/rotational malunion
- functional gait abnormality
- painful lamenss d/t 2* OA
- What position should the leg be fixed in?
- normal standing position
- unless joint extension/flexion needed d/t soft tissue
- How many joints are immobbiised with a fx?
> one above and one below
- most conventional splints cannot be used above the stifle/elbow so need surgical correction
- spica splints can eb constructed to immobilise hip/shoulder
See lecture for diagram on immoobilising fx
-
How often is external coaptation used?
> infrequently
- hard to manage, severe complications, often better ways
commonly used for support after surgery esp arthrodesis (for 6 weeks)
Types of external coaptation?
> Robert JOnes - thick - modified RJ thinner > spinted > bilvalved cast - allowws frequent changes without ... > Spica spint - immobilise shoulder/hip > Schroeder-Thomas?? > Walking bar - aluminium bar at end of cast - for digit fx
What is external coaptation dressing made up with?
- primary layer
- cover and protect, absorb discharge, wet to dry debriding
- eg. melolin, allevyn - secondary layer
- absorption, support and pressure
- cotton wool (do not let it contact skin!!)
- cast padding (less bulky, conforms better)
- conforming gauze wrapped over to provide stability and occasionally compression
+- casting tape for fx - tertiary layer
- holds inner layers, barrier against physical abrasion and environmental contaminantss
- elastic conforming bandage most common
- if this layer appears wet with discharge bacterial infection is possible - change the bandage!! - +- stirrups
Advantages of external coaptation?
- cheap (providing no complications)
- avoids surgery
Disadvantages of external coaptation?
- stable, min displaced fx
- can -> bone/limb malalignment
- can cause serious complications
- complications more expensive /difficult to tx than original fx!
- difficult to manage (slip, wet)
Potential complications d/t external coaptation?
- distal limb oedema/swelling (leave toes exposed to check)
- skin rubbing, ulcers, necrosis (can use ‘donuts’)
- soft tissue necorsis
- cast slippage
> amputation may be only option
How can risks associated with external coaptation bandages eb minimised?
- only use if necessary
- plenty of padding esp bony prominence
- change q1week initially then q2weeks
- owner check daily for swelling and smell
How regularly do casts need to be changed in puppies?
Weekly to compensate foro bone growth
Outline the slater-harrie classification system. Which type of fx is this applicable to? LOOK UP
- Fx across a growth plate (physis) = SALT pnumonic
> type I: Slipped
fracture plane passes all the way through the growth plate, not involving bone, cannot occur if the growth plate is fused reference required -good prognosis
> type II: Above
fracture passes across most of the growth plate and up through the metaphysis, good prognosis
> type III: Lower
fracture plane passes some distance along the growth plate and down through the epiphysis, poorer prognosis as the proliferative and reserve zones are interrupted
> type IV: Through or transverse or together
intra-articular
fracture plane passes directly through the metaphysis, growth plate and down through the epiphysis, poor prognosis as the proliferative and reserve zones are interrupted
> type V: Ruined or rammed
crushing type injury does not displace the growth plate but damages it by direct compression, worst prognosis
If a fx came in as an emergency and could not be reduced until the next day, how would you manage the patient while waiting?
- rest
- restricted activity
- NSAIDs
- opioids
+- cold compress
+- sling
What causes carpal hyperextension and how can it be treated?
rupture of palmar carpal ligaments and fibrocartilage, usually 2* to trauma
> Tx: pancarpal arthrodesis
- castless plate applied (special one for carpal arthrodesis with differnet sized screws
Which side of a fx are splints usually placed? Exception? What effect does this have and how can these problems be overcome? What risks might occour 2* to this!?
- usually on tension side
- for carpal arthrodesis must go on dorsal aspect (compressive side)
> ^ risk bend and breakage - to compensate, use external coaptation to protect implant and reduce the forces
> risk of cast sores and cast slippage - do not place immediately postop, place RJ for 3-5d then cast when swelling educed
- monitor 24hrs before sending home
- change weekly d remove @6weeks
How can distal limb integrity be assessed?
Needle in foot pad - if frank blood comes out then tissue is still viable
Potential roles of external coaptation ?
- temporary first aid
- 2* support after surgical intervention
- 1* support and stabilisation of selected fx
