Coaptation Flashcards
what is coaptation?
casting/splinting/bandage
what forces are casts good at preventing against? what forces do they not prevent against?
good for: bending and rotation
not good for: axial compression forces- dogs and cats are still weight-bearing
what types of fractures are casts good for?
- simple transverse
- or fractures with internal support: metacarpal, paired bones like radius/ulna
- partial fractures
T/F: casts are not suitable for unstable oblique or comminuted fractures
true!
what will allow a cast to work well?
IMMOBILIZATION of the joint above AND below the fracture
ex: fracture below elbow or stifle is hard to immobilize elbow or hip
for coaptation, you need fracture reduction. what is this?
requires >50% of true overlap of fractured ends for predictable healing : allows you to predict the bones staying in place for healing
BEWARE OF RADIOGRAPHIC PROJECTION! need your worse 2 radiographic views, and take rads after your coaptation because process of applying cast could cause things to shift
what is the difference between a cast vs splint?
cast: superior against rotation
ex: single metacarpal bone: can likely splint
- splint is step down from cast; typically on lateral aspect of the limb and animals tolerate better. if halfway thru bone healing process can switch to splint
splint: use for soft tissue injuries: sprain or strain
what is the difference between strain vs sprain?
sprain: ligament
strain: tendon
what is the preferred material for a splint?
hexalite/vet lite: heat remoldable polymer than you can add layers of to shape to the leg
what morbidities can occur as a result of coaptation?
- no joint ROM
- muscle atrophy
- osteopenia
- pressure sores
- dermatitis
- bandage change rechecks need to happen! weekly!!
- maintenance and care
why do we change bandages weekly in dogs/cats?
they are mobile and have movement: will chew it, pee on it, use it, etc
T/F: bandage morbidity can be worse than original injury
true! why weekly bandage changes are important
why can joint immobility lead to joint damage during coaptation?
because it is the range of motion that pumps synovial fluid nutrients into the joint: so the cartilage isn’t being fed: will get arthritis if immobilized for a long time
especially young developing joints need the surfaces of the joint in contact!!
what is muscle contracture?
healthy muscle replaced by fibrous scar tissue
no longer can flex joints depending on what muscle it affects
muscle atrophy can occur, contracture: negative ramifications of coaptation
what are walking bars?
cast + walking bars
- used for fractures distal to the carpus/tarsus
- try and carry cast past the end of the toes so the pt is walking on the cast so they aren’t putting force on the fraction zone
- patient is walking on the cast to avoid digits contacting the ground
can you cast a comminuted fracture?
no, will shear and get worse
a 6 y/o yorkie presents with a distal diaphyseal radial and ulnar fracture. it is simple transverse, and caudally and laterally displaced. would you coapt this? why or why not?
NO! toy breeds have poor blood supply to the distal radius and ulna
= very slow bone healing
AVOID COAPTATION
