Contributors: Justin Goggin, Patsy Whelehan

 Species: Canine   |   Classification: Techniques

Introduction Requirements Preparation Procedure Aftercare Outcomes Further Reading

Introduction

  • A high detail film-screen combination is required.
  • A grid is not required.
  • In UK, kV should not exceed 60.
  • 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.

Uses

  • Fracture, especially of the humeral condyles Bone fracture (medial humeral condyle) - radiograph CrCd Elbow Y-fracture - radiograph.
  • Dislocation Elbow dislocation - radiograph.
  • Incomplete ossification of the humral condyle, fragmented medial coranoid process, elbow dysplasia (osteochondrosis Osteochondrosis Elbow OCD (for DJD) - radiograph lateral Elbow OCD - radiograph CrCd , ununited anconeal process Ununited anconeal process Elbow ununited anconeal process 01 - radiograph , elbow incongruity).
  • Inflammatory, infectious, degenerative and traumatic osteoarthrosis.
  • Neoplasia, but unusual site.
  • Osteomyelitis.

Advantages

  • Non-invasive.
  • Procedure easily performed in private practice.

Time Required

Preparation

  • Dependent upon the method of chemical restraint (GA or sedation).

Procedure

  • 10-15 min or longer, dependent upon skill of radiographer.

Decision Taking

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
  • A minimum of two orthogonal views (craniocaudal and lateral views) are necessary for radiographic evaluation.
Lateral
  • Standard projection.
Craniocaudal
  • Essential in cases of suspected fracture and to localize lesions detected on lateral view Radiographic positioning video: elbow - craniocaudal view.
    For optimum demonstration of the proximal radius and ulna, use positioning method option 1. For optimum demonstration of the distal humerus, use option 2.
Lateral in full flexion
  • Reveals more of the anconeal process when looking for osteochondrosis.

Risk assessment

Craniocaudal oblique views
  • Cranial 15°-20° lateral-caudomedial view:
    • Recommended to evaluate for fragmentation of the medial coranoid process and humeral condyle osteochondritis dissecans (OCD).
  • Cranial 15 ° medial-caudolateral view.
    • Recommended to evaluate for incomplete ossification of the humeral condyle.

Requirements

Personnel

Other involvement

  • Radiographer or veterinary nurse/technician carrying out radiography.

Materials Required

Minimum equipment

  • X-ray machine.
  • Cassettes with high detail screens.
  • Film ID system.
  • Processing facilities.
  • Immobilization and positioning aids: sandbags, foam wedges, 1" tapes or roll gauze.
  • Protective clothing (lead-rubber aprons, gloves and thyroid shields).

Ideal equipment

  • High output X-ray machine.
  • Rare Earth high detail screens.
  • Automatic processing facilities.
  • Film ID camera.

Minimum consumables

  • ID card or tape.
  • X-ray film.
  • Pharmaceuticals for chemical restraint.

Preparation

Restraint

  • 1-2 competent people.
  • Sandbags.
  • Foam wedges.
  • Tape or roll gauze.
  • Positioning trough.
  • Positioning blocks.

Procedure

Core Procedure

Step 1 - Lateral

  • Position the patient in lateral recumbency on the side to be examined and immobilize.
  • Use a sandbag or tie to hold the contralateral limb caudally and dorsally away from the field.
  • Use padding under the shoulder and carpus as necessary to ensure that the humerus and the radius and ulna are parallel to the film. This is essential to ensure a true lateral position for the elbow.
  • The elbow should be flexed to approximately 90degrees.
  • Palpate the humeral epicondyle Radiographic positioning elbow - lateral projection (with full flexion) , which will be more prominent on the lateral aspect.
  • Center the vertical beam at this point Radiographic positioning elbow - lateral projection.
  • Collimate to include the distal third of the humerus, the proximal third of the radius and ulna, and the soft tissues around the joint Elbow normal 01 - radiograph lateral.

Step 2 - Craniocaudal: option 1

  • 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 elbow.
  • Place the thin end of a 15° foam wedge between the elbow and the film Radiographic positioning elbow - craniocaudal projection. 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 Radiographic positioning elbow - craniocaudal projection (landmarks).
    Positioning both hindlimbs to the side opposite the affected forelimb will help to achieve accurate positioning.
  • Center the vertical beam through the 'crease' of the elbow.
  • Angling the tube head 15-30° will reduce distortion of the image.
  • Collimate to include the distal third of the humerus, the proximal third of the radius and ulna, and the lateral skin surfaces Elbow normal - CrCd radiograph.

Step 3 - Craniocaudal: option 2

  • Place the patient in dorsal recumbency, with a positioning trough at hip level, and immobilize.
  • Extend the affected limb caudally and secure with a tie.
    Elevate the film and the elbow on blocks so that the humerus lies flat.
  • Rotate the thorax to achieve a true craniocaudal position of the limb.
  • Center the vertical beam through the 'crease' of the elbow Radiographic positioning elbow - craniocaudal (alternative) projection.
  • Collimate to include the distal third of the humerus, the proximal third of the radius and ulna, and the skin surfaces lateral to the joint.

Step 4 - Lateral with full flexion

  • Position the patient in lateral recumbency on the side to be examined and immobilize.
  • Use a sandbag or tie to hold the contralateral limb caudally and dorsally away from the field.
  • Use padding under the shoulder and carpus as necessary to ensure that the humerus and the radius and ulna are parallel to the film. This is essential to ensure a true lateral position for the elbow.
  • A wedge may also be necessary under the sternum to maintain this position.
  • The elbow should be flexed as fully as possible.
    There is a tendency for the elbow to become retracted towards the thorax when positioning for this projection. This can be avoided by positioning the contralateral limb more dorsally, thus rotating the thorax away from the affected elbow. However, care must be taken not to pull the elbow out of the true lateral position. Adjust the padding under the shoulder as necessary.
  • Palpate the humeral epicondyle, which will be more prominent on the lateral aspect.
  • Center the vertical beam at this point.
  • Collimate to include the distal third of the humerus, the proximal third of the radius and ulna, and the soft tissues around the joint.

Step 5 - Oblique views: cranial 15 degree lateral-caudomedial oblique and cranial 15 degree medial-caudolateral oblique views

  • Position limb as described for the craniocaudal projection, but internally rotate 15-20° for cranial lateral-caudomedial view, and externally rotate 15° for the craniomedial to caudolateral oblique view.

Aftercare

Outcomes

Reasons for Treatment Failure

  • Inadequate sedation.
  • Incomplete study (a minimum of a lateral and craniocaudal view should be obtained).
  • Inaccurate positioning or centering, wrong exposure factors, failure to label film, failure to collimate appropriately.
  • Poor processing.
  • Equipment failure.

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Boulay J P (1998) Fragmented medial coronoid process of the ulna in the dog. Vet Clin North Am Small Anim Pract​ 28 (1), 51-74 PubMed.
  • Miyabayashi T, Takiguchi M, Schrader S C et al (1995) Radiographic anatomy of the medial coronoid process of dogs. JAAHA 31 (2), 125-132 PubMed.
  • Marcellin-Little D J, DeYoung D J, Ferris K K et al (1994) Incomplete ossification of the humeral condyle in Spaniels. Vet Surg 23 (6), 475-487 PubMed.