Juvenile Bone Disease

What is osteochondrosis?

Dysfunction of normal endochondral ossification

What is radiographically seen with osteochondrosis?

Concave subchondral bone defect

Osteochondrosis can progress to _______ with repeated concussion.

Osteochondrosis dissecans

How does osteochondrosis dissecans happen?

Repeated concussion causing cartilage flap to separate from bone

True or False: the cartilage flap can always be seen radiographically.

False - must be ossified

True or False: osteochondrosis dissecans is a completely separate disease from osteochondrosis.

False

Where will the subchondral defect be located in shoulder OC/OCD?

Caudal aspect of humeral head

Where will the subchondral defect be located in elbow OC/OCD?

Distal medial aspect of the humerus

True or False: elbow OC/OCD is a component of elbow dysplasia.

True

In elbow OC/OCD, you ______ see mineralized flap.

Rarely

OC/OCD is often accompanied by surrounding _______.

Sclerosis

Where will the subchondral defect be located in stifle OC/OCD?

Distal aspect of femoral condyle

True or False: joint effusion is rarely seen in stile OC/OCD.

False

What structure in the hindlimb can be confused for OCD?

Extensor fossa

Where will the subchondral defect be located in tarsal OC/OCD?

Medial trochlear ridge of talus

Retained Cartilagenous Core is a flame-shaped radiolucent area from the level of the physis to metaphysis.

True

Where is retained cartilagenous core usually seen?

Distal ulna

What is the most common elbow developmental disorder?

Fragmented medial coronoid process (FMCP)

True or False: fragmented medial coronoid process is a component of hip dysplasia.

False - elbow dysplasia

How does fragmented medial coronoid process appear on a lateral view?

Blunted appearance to medial coronoid process

How does fragmented medial coronoid process appear on a CC view?

New bone production on medial coronoid process

How does an ununited anconeal process occur?

Forms from a separate center of ossification

The lucent line of an ununited anconeal process is been seen on which view?

Flexed lateral

True or False: ununited anconeal processes are components of elbow dysplasia.

True

What joint is NOT involved in elbow incongruity?

Humero-scapular

What is elbow congruity a component of?

Elbow dysplasia

What is radiographically seen with elbow incongruity?

Step between humero-radial and humero-ulnar joints

List the four processes associated with elbow dysplasia.

Ununited anconeal process, fragmented coronoid process, OC lesion medial aspect of distal humeral condyle, elbow incongruity

True or False: panosteitis predominantly affects females.

False

Panosteitis affect ____% of males.

70-80

How does panosteitis present?

Shifting leg lameness

Which radiographic finding is NOT initially seen with panosteitis?

Step between humero-radial and humero-ulnar joints

Which radiographic finding is NOT seen with late panosteitis?

Thumbprint appearance

True or False: hypertrophic osteodystrophy is a systemic illness.

True

Where is hypertrophic osteodytrophy likely to occur?

Distal radius/ulna/tibia

Which is NOT a radiographic sign of hypertrophic osteodytrophy?

Thin radioopaque band above physis in the metaphyseal portion of long bones

What is the most common orthopedic disease in dogs?

Hip dysplasia

Hip dysplasia is an ______ disease.

Inherited

Radiographically, where are you looking for hip dysplasia?

Obturator foramen

How much coverage of the femoral head should there be with NORMAL anatomy?

50%

True or False: the femoral neck should be wider than the femoral head.

False

What can form along the acetabular rim and dorsal edge in patients with hip dysplasia?

Periarticular osteophytes

What is the morgan line?

Enthesiophyte formation on the distal aspect of the femoral neck

What is the morgan line secondary to?

Coxofemoral joint laxity

True or False: the morgan line is a late sign of DJD.

False - early

True or False: avascular femoral head necrosis is found in large breed dogs.

False - small and toy

What is an alternative name for avascular femoral head necrosis?

Legg-Calve-Perthes disease

What is NOT a radiographic finding of avascular femoral head necrosis?

Luxation of femoral head