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