Week 3 Lesson 21 Diagnostic imaging of the thoracic limb of SA

What are the standard radiographic projections for the thoracic limb in dogs and cats?

The standard projections are medio-lateral and cranio-caudal or caudo-cranial views.

What is the common position for a medio-lateral view of the shoulder joint?

Right or left lateral recumbency with the affected limb down, pulled cranially and ventrally.

Which radiographic view is best suited to profile the humeral tubercles and the intertubercular groove?

The skyline view.

How should a patient be positioned for a caudo-cranial view of the humerus?

In dorsal recumbency with the forelegs extended cranially.

What is the specific indication for a flexed medio-lateral view of the elbow?

It is used to evaluate the anconeal process, specifically for conditions like an ununited anconeal process.

Which anatomical plane divides the animal into equal right and left halves?

The median plane.

What abbreviation is used for a ventrodorsal projection?

VD.

What are the five components of the mnemonic used to assess a normal mature bone?

Alignment, Bone, Cartilage, Device, and Envelope.

What is the "Envelope" in the ABCDE assessment of a radiograph?

It refers to the soft tissues surrounding the bone or "everything else".

Where are marrow elements contained within a long bone?

Within the central medullary cavity.

What are the three main sections of a long bone cylinder?

The diaphysis, epiphysis, and metaphysis.

Except where there is articular cartilage, what vascular connective tissue covers the bone surface?

The periosteum.

What tissue lines the inner surface of the bone cortex?

The endosteum.

Normal mature bone is approximately what percentage mineralized?

50% to 70%.

Which part of the bone is denser and more opaque: the compact cortical bone or the spongy cancellous bone?

The compact cortical bone.

How does the diaphysis of feline long bones generally compare to those of dogs?

In cats, the long bone diaphyses tend to be straighter.

What term describes the specialized radiolucent band found between the epiphysis and metaphysis in young animals?

The physis or growth plate.

What remains visible at the site of a growth plate once an animal reaches skeletal maturity?

A faint radiopaque line called the physeal scar.

At what age does the supraglenoid tubercle of the scapula typically close?

Between 4 and 7 months.

What is the approximate age of closure for the distal humerus condyle?

6 weeks.

What is the approximate age of closure for the distal radius and ulna?

6 to 12 months.

When does the accessory carpal bone typically show physeal closure?

2 to 5 months.

What anatomical landmark on the scapula is a diagonal linear opacity that merges with the deltoid tuberosity?

The tricipital line.

On which aspect of the proximal third of the humeral diaphysis is the deltoid tuberosity located?

The lateral aspect.

What is the name of the large radiolucency in the distal humerus that is engaged by the anconeal process in dogs?

The supratrochlear foramen.

Which foramen is found on the medial aspect of the distal humeral diaphysis in cats but not in dogs?

The supracondylar foramen.

How does the olecranon process of the elbow appear in cats compared to dogs?

It appears squarer in cats.

Which breeds are classified as chondrodystrophic, often displaying short, bowed limbs?

Basset Hounds, Corgis, and Bulldogs.

What radiographic finding is characteristic of chondrodystrophic breeds?

Short, wide diaphyses with marked craniolateral bowing and curvature.

What is the primary landmark on the cranial aspect of the scapula?

The spine.

What are the two fossae divided by the scapular spine?

The supraspinous fossa and the infraspinous fossa.

What process is located at the distal end of the scapular spine?

The acromion.

Which scapular process is unique to the feline species?

The metacromion.

What is the name of the articular surface of the scapula that meets the humeral head?

The glenoid cavity.

What tuberosity is located just distal to the glenoid cavity?

The infra-glenoid tuberosity.

What is the name of the groove located between the greater and lesser tubercles of the humerus?

The intertubercular or bicipital groove.

Which humeral tubercle is generally larger and located laterally?

The greater tubercle.

What is the name of the rounded articular surface on the lateral aspect of the humeral condyle?

The capitulum.

What is the name of the pulley-like articular surface on the medial aspect of the humeral condyle?

The trochlea.

Which epicondyle of the humerus is typically larger and more prominent?

The medial epicondyle.

What is the primary function of sequential radiographic studies?

To assess the degree of improvement or deterioration of a disease process over time.

List three clinical indications for radiographic imaging of a thoracic limb.

Lameness, swelling, and muscle atrophy.

What are radiographs used to assess in the case of a fracture?

Healing and callus formation.

Which bone assessment category involves looking for evidence of articular or joint pathology?

Cartilage.

What should be evaluated if orthopaedic implants are present in a bone?

Evidence of loosening, failure, or osteomyelitis.

How should the external surface of cortical bone appear on a radiograph?

Smoothly marginated, except at muscle and tendon insertion points.

What is the radiographic appearance of the medullary cavity in a normal mature radius?

Generalized radiolucency throughout.

Which bone in the antebrachium tapers as it extends distally?

The ulna.

Where is the ulnar cortex typically thicker?

In the proximal third of the diaphysis.

What is the name of the joint between the radius and the ulna?

The radio-ulnar joint.