Miscellaneous bone and joint conditions

Question 1

Avascular necrosis (AVN) of the femoral head

Answer 1

Ischaemic necrosis

Small breeds

From 5 months

Pain - hip extension and flexion

Muscle wastage

Question 2

Radiographic findings of avascular necrosis of the femoral head

Answer 2

Lucent areas initially

Collapse and mushrooming

Question 3

Treatment of avascular necrosis of the femoral head

Answer 3

Surgery
○ Femoral head and neck excision
○ Total hip replacement

Conservative
○ Cage rest
○ NSAIDs

Question 4

Panosteitis

Answer 4

Endostosis, fibrous osteodystrophy, juvenile osteomyelitis, eosinophilic panosteitis

Focal areas of endosteal bone proliferation

Age 5-18 months

Species - dogs

Breeds - large especially GSDs

Male > female

Question 5

Aetiopathogenesis of panosteitis

Answer 5

Viral, excess nutrition, genetic?

Question 6

Histopathology of panosteitis

Answer 6

Degeneration of medullary adipocytes

Stromal cell proliferation

Intramembranous ossification

Question 7

Clinical signs of panosteitis

Answer 7

Lame, non-weight bearing, shifting

Dull, anorexia, pyrexia

Question 8

Physical examinationof panosteitis

Answer 8

Painful bones on palpation

Question 9

Radiography of panosteitis

Answer 9

Patchy increased density of medullary bone
○ Distal humerus
○ Proximal ulna
○ ‘Thumbprints’
○ Near nutrient foramen

Take radiographs of the whole bone and stand back

Loss of distinction between cortex and medulla

Question 10

Signalment of craniomandibular osteopathy

Answer 10

Breeds - Terriers, esp. WHW, Scotties, Bostons, and Cairns

Age: 3-8mo

Male = female

Question 11

Aetiology of craniomandibular osteopathy

Answer 11

Genetic - autosomal recessive - WHWT

Hormones? - low risk after neutering

Infectious? Virus? CDV? - unproven

Irish setters show similar signs with canine leucocyte adhesion deficiency - fatal

Question 12

Physical examination of craniomandibular osteopathy

Answer 12

Palpably enlarged mandibles

Limited mouth opening

Pain on attempting to open mouth or palpation of jaw

Question 13

Radiography of craniomandibular osteopathy

Answer 13

Proliferative new bone on mandibles

Sometimes on TMJs

On bullae

Question 14

Treatment of craniomandibular osteopathy

Answer 14

Analgesia and anti-inflammatories

NSAIDs/steroids

Tramadol/methadone/morphine

Liquefied food, hospitalisation, feeding tube

Usually good prognosis as it is a self-limiting disease
○ Can interfere with prehension/respiration

If very severe - may require euthanasia

Question 15

Signalment of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 15

Breeds - large and giant breeds
○ Occasionally smaller breeds

Age 2-8 months

Male = female

Question 16

Aetiology of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 16

Hypovitaminosis C

Infection - CDV

Hereditary

Excess nutrition

Copper deficiency

Question 17

Clinical signs of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 17

• Wax and wane
  
  • Inappetance
  • Pyrexia
  • Reluctance to stand
  • Reluctance to move
  • Prior GIT upset?

Question 18

Physical examination of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 18

Swollen hot metaphyses of lower limb bones

VERY painful - care - may bite!

Pyrexia

Mild lymphomegaly

Question 19

Radiography of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 19

Sclerotic line immediately adjacent to physis

Radiolucent zone adjacent to sclerotic line (Tummerfield zone)

Periosteal new bone formation

Question 20

Treatment of metaphyseal osteopathy (hypertrophic osteodystrophy)

Answer 20

Balanced diet/no supplements

Rehydrate

Analgesia - NSAIDs/opiates/rest

Antibiotics/steroids

Mild cases will respond, more severe cases may need hospitalisation

Prolonged recovery and may lead to GP closure and deformity

Question 21

Hypertrophic osteopathy (Marie’s disease) (hypertrophic pulmonary osteoarthropathy)

Answer 21

Hypertrophic new bone formation around distal bones

Secondary manifestation of thoracic (abdominal) disease

In 90% of cases there is pulmonary neoplasia

Question 22

Pathogenesis of Hypertrophic osteopathy (Marie’s disease) (hypertrophic pulmonary osteoarthropathy)

Answer 22

Neurovascular reflex - afferent vagal and intercostal fibres irritation

Stimulation of efferent fibres in connective tissue and periosteum of limbs
○ Increase in blood flow
○ Overgrowth of vascular connective tissue
○ New bone formation

Prognosis is guarded as it is often a malignant neoplasm

May get regression of bony changes after mass removal