Lt 12 Developmental Bone Disease

Although radiographic signs vary by etiology, most are _____ in radiographic appearance

non-aggressive

Many degenerative diseases cause ______ lesions. Therefore, the other limb should always be radiographed for comparison.

bilaterally symmetric

Many developmental diseases result in _____

Degenerative joint disease

______ is failure of normal endochondral ossification caused by necrosis of epiphyseal cartilage

Osteochondrosis

Osteochondrosis leads to _____

divots in subchondral bone, progressive chondromalacia, and eventual defects in the articular surface

What factors can contribute to Osteochondrosis?

Anatomic conformation,

Rapid growth,

Nutrition,

Trauma/ischemia,

Hormonal influences

Clinical presentation for Osteochondrosis

Young, rapidly growing, large breed dogs;

Male >>> Female;

6-9 months old

What is the most common weight-bearing articular surface that gets Osteochondrosis?

Caudal aspect of the humeral head

Radiographic findings associated with Osteochondrosis?

Flattened or concave lucent defect in the subchondral bone.

Surrounded by bony sclerosis.

Widening of the joint space.

Synovial effusion/hypertrophy.

What is being highlighted by this image?

Osteochondrosis

Osteochondrosis Dissecans means that _____

Cartilage flap is present; "Joint mouse"

What is being highlighted in this image?

- Specifically the long arrow

Joint mouse

Prognosis for Osteochondrosis Dissecans

Caudal humeral head has excellent prognosis w/ treatment.

Fair to guarded prognosis for all other sites.

What is the most obvious/striking abnormality of this tarsus?

Degenerative changes and intracapsular soft tissue swelling

Is this a primary abnormality or is it secondary to some other process?

Secondary

What is the diagnosis for this image?

Osteochondrosis Dissecans

What is the next step for this patient?

Radiograph the other tarsus

Elbow dysplasia is a non-specific term for what 4 diseases that can affect the elbow?

1. Osteochondrosis (Distomedial aspect of humeral condyle/trochlea)

2. Ununited anconeal process.

3. Fragmented medial coronoid process.

4. Joint incongruity.

Ununited anconeal process is a common cause of Elbow dysplasia for _____

Large-breed dogs; Male >>> Female

Radiographic findings for Ununited anconeal process

Lucent line separating the anconeal process from the olecranon beyond 150 days

An ununited anconeal process can NOT be diagnosed until ______

5 months of age

What radiograph view needs to be taken to diagnose an ununited anconeal process?

Flexed lateral

Prognosis of an ununited anconeal process is ____

depends on degree of osteoarthritis and response to surgery

What is the MOST COMMON developmental disease of the cubital joint?

Fragmented Medial Coronoid Process

What part of the bone is being highlighted in this image?

- Normal presentation for this structure

Medial coronoid process

Radiographic findings for a

Fragmented Medial Coronoid Process

- Osteophyte formation on anconeal process and radial head.

- Indistinction or abnormal contour of cranial margin.

- Sclerosis of subchondral bone of Trochlear notch.

- Joint incongruity.

What is the BEST diagnostic tool for identifying a Fragmented Medial Coronoid Process?

Arthroscopy > CT > Radiographs

What is being highlighted in this image?

Elbow dysplasia; Fragmented medial coronoid process and Ununited anconeal process

Aseptic Necrosis of the Femoral Head is also called _____

Legg-Calve-Perthes disease

Aseptic Necrosis of the Femoral Head is common for _____

Young, SMALL-breed dogs; NO sex predisposition

Aseptic Necrosis of the Femoral Head is caused by _____

Compromised blood supply to the femoral capital epiphysis

Aseptic Necrosis of the Femoral Head progresses to _____

Subchondral bone necrosis and remodeling of the femoral head

Radiographic findings for Aseptic Necrosis of the Femoral Head

- Lucent areas within the epiphysis and metaphysis.

- Flattening of the femoral head.

- Linear lucent areas within the subchondral bone.

What is the treatment of choice for Aseptic Necrosis of the Femoral Head ?

Femoral head and neck ostectomy; Tx is palliative.

What diagnostic needs to be done to confirm Aseptic Necrosis of the Femoral Head?

Histopathology

_______ is a condition that causes delayed closure of the capital physis and multiple other growth plates in cats.

Contains abnormal clusters of chondrocytes and excessive connective tissue.

Physeal Dysplasia

The capital physis normally closes around ______

7.5 to 11 months old

What condition is being highlighted in this image?

Physeal Dysplasia

Clinical presentation for Physeal Dysplasia?

Spontaneous fracture of the capital physis NOT associated with trauma;

Male cats >>> Female cats;

Obese;

VERY often bilateral condition

What are the radiographic signs of Physeal Dysplasia?

- Femoral head and neck lysis with sclerosis and remodeling.

- Capital Physeal fracture.

-Metaphyseal resorption with chronicity.

Treatment for Physeal Dysplasia

Femoral head and neck ostectomy; Tx is palliative.

9 month old, MN, Golden retriever with right forelimb lameness and pain on shoulder extension

Osteochondrosis

1.5 year old, FS, Golden retriever with a hopping gait, pain on hip extension, decreased thigh musculature, and a positive Ortolani sign

Hip dysplasia

1 year old, MI, German shepherd with bilateral thoracic limb lameness with pain on elbow flexion

Elbow dysplasia; Fragmented medial coronoid process and Ununited anconeal process

7 month old, MN, Rottweiler with right forelimb lameness and pain on elbow flexion

Elbow dysplasia; Fragmented medial coronoid process and Ununited anconeal process

1 year old, FS, Toy poodle with a sudden non-weight bearing lameness of the left pelvic limb, decreased left thigh musculature, and pain on left hip extension

Aseptic Necrosis of the Femoral Head and Neck

_______ is a self-limiting idiopathic disease of the long bones.

Increased osteoblastic and fibroblastic activity in the medullary cavity, endosteum, and periosteum.

Panosteitis

Does inflammation play a role in Osteitis?

No, its a misnomer

Clinical presentation for Panosteitis

large breed dogs;

Males >>> Females;

5-12 months old up to 7 years old

Clinical presentation for Osteitis

Pain on palpation of the diaphysis of the long bones

Radiographic findings of Osteitis

increased opacity of the diaphyseal medullary cavity of long bones; Often near the nutrient foramen

Is this an early or late presentation of Osteitis? Why?

Early presentation; Patchy and heterogenous lesion

What would a late presentation of Osteoitis look like?

Diffuse and homogenous lesion

Prognosis for Osteitis is ____

Excellent and often self-limiting

Treatment for Osteitis

Rest,

Analgesics,

Weight management

What is being highlighted in this image?

Osteitis of the radius and ulna

Causes of Hypertrophic Osteodystrophy

Oversupplementation of vitamins and minerals,

Hypovitaminosis C,

Sterile inflammation,

Canine distemper virus

What of Hypertrophic Osteodystrophy?

Neutrophilic inflammation of the metaphysis causing necrosis, hemorrhage, and increased osteoclasts —> Collapse of the metaphysis.

Congestion and edema in surrounding tissues.

Clinical presentation for Hypertrophic Osteodystrophy?

Large breed dogs; 2-8 months old

Swollen, firm, and painful metaphyseal region of long bones.

Fever, lethargy, anorexia.

Radiographic findings for Hypertrophic Osteodystrophy

Lucent zones int he metaphysis that are parallel to the physis -> "Double Physeal line sign".

Subchondral bony sclerosis.

Irregular widened physis.

Which bones is Hypertrophic Osteodystrophy most common in?

Distal radius and ulna

What is being highlighted in this image?

Hypertrophic Osteodystrophy; "Double Physeal sign"

Prognosis for Hypertrophic Osteodystrophy

Good with treatment and usually self-limiting.

Premature Physeal closure or permanent bony changes.

Treatment for Hypertrophic Osteodystrophy

Analgesics,

IV fluids,

Decreased caloric intake in fast-growing dogs

8 month old, MI, German shepherd with right thoracic limb lameness, sometimes switches to left thoracic limb lameness

Panosteitis; Multifocal, ill-defined, ovoid to irregularly shaped sclerotic lesions of the humeral, radial, ulnar diaphyses.