Contributors: Patsy Whelehan
Species: Feline | Classification: Techniques
- A high definition film-screen combination is required.
- A grid is not required.
- kV should not exceed about 50.
- Soft tissues should be included.
- General anesthesia or heavy sedation is required.
- The film should be correctly exposed and developed, and free from movement blur and artifact.
- The anatomical marker must be clearly visible, along with the patient's identification, the date, and the name of the hospital or practice.
- Fracture Fracture: overview .
- Neoplasia (distal radius).
- Premature distal ulna growth plate closure (angular limb deformity).
- Dependent upon the method of chemical restraint (GA or sedation).
- 10 to 15 minutes, or longer, dependent upon skill of radiographer.
Criteria for choosing test
Is the examination appropriate?
- Can you make the diagnosis without it?
- Can it tell you what you need to know?
- Will your management be affected by the radiological findings?
Choosing the right projections
- Standard projection.
- Standard projection.
- Two views always necessary.
- Radiographer, or Technician carrying out radiography.
- X-ray machine.
- Cassettes with high definition screens.
- Processing facilities.
- Immobilization and positioning aids: sandbags, foam wedges, tying tapes.
- Protective clothing (lead-rubber aprons).
- High output X-ray machine.
- Rare earth high definition screens.
- Automatic processing facilities.
- X-ray film.
- Pharmaceuticals for chemical restraint.
- One to two competent people.
- Foam wedges.
- Tying tapes.
Step 1 - Lateral
- Position the patient in lateral recumbency on the side to be examined and immobilize.
- Use padding under the shoulder and carpus as necessary to ensure that the radius and ulna are parallel to the film and in a lateral position .
- Check that both the elbow and the carpus are in the true lateral position.
- Secure the limb at the carpus.
- Center with a vertical beam at mid-shaft level.
- Collimate to include both the antebrachio-carpal joint and the elbow, and the skin surfaces on the cranial and caudal aspects .
Step 2 - Craniocaudal
- Place the patient in sternal recumbency.
- Extend the affected limb as far cranially as possible and secure .
If the elbow and shoulder are not in full extension it will be very difficult to maintain an unrotated craniocaudal position of the radius and ulna.
- Place the thin end of a 15 degree foam wedge between the elbow and the film. This will facilitate achieving the true craniocaudal position.
- Rotate the limb until the point of the elbow is palpable beneath the middle of the cranial aspect ie until the elbow is in a true craniocaudal position.
To prevent the elbow from slipping laterally, place padding at the lateral aspect, with a heavy sandbag lateral to that.
- Secure the limb at the carpus if necessary.
- Center mid-shaft.
- Collimate to include both joints (and as far as the metacarpals in the case of angular limb deformity) and the skin surfaces laterally and medially .
Reasons for Treatment Failure
- Inadequate sedation.
- Poor technique: inaccurate positioning or centering, wrong exposure factors.
The most common positioning problem is rotation in the craniocaudal position.
- Follow the tips to ensure that this does not happen.
- Poor processing.
- Equipment failure.