Investigation of Joint Disease

Question 0

What are the two types of synoviocytes?

Answer 0

Type A and Type B

Question 1

What is a joint made up of?

Answer 1

Hyaline articular cartilage
Articular capsule made up of fibrous capsule and synovial membrane
Joint cavity containing synovial fluid as well as ligaments and tendons

Question 2

What is joint fluid?

Answer 2

Dyalisate from plasma filtered through the vascular endothelium and synovial interstitium
Contains proteins, electrolytes, enzymes, water and HA

Question 3

What occurs in an inflamed joint?

Answer 3

Excessive synovial fluid in joint cavity
Soft tissue inflammation
White blood cells exit blood vessel and enter synovial fluid and release inflammatory mediators

Question 4

What are the two broad categories of arthritis?

Answer 4

Non-inflammatory (WBC3000/ul, PNC)

Question 5

What are the three further classifications of non-inflammatory arthritis?

Answer 5

Traumatic
DJD
Haemarthrosis

Question 6

What are the two further categories to further classify inflammatory arthritis?

Answer 6

Non-infectious and infectious

Question 7

What are the possible causes of inflammatory arthritis?

Answer 7

Bacterial, viral, fungal, rickettsial, protozoal, borrelial, mycoplasmal

Question 8

How are non-infectious inflammatory diseases further classified?

Answer 8

Immune based = erosive or non-erosive

Non-immune based = crystal or neoplastic

Question 9

What are some causes of erosive immune-based non-infectious inflammatory arthritis?

Answer 9

Rheumatoid arthritis
PA greyhound
Feline chronic progressive PA

Question 10

What are some causes of non-erosive immune-based non-infectious inflammatory arthritis?

Answer 10

SLE
Idiopathic PA
PA/PM syndrome
PA/meningitis syndrome
PA Akita

Question 11

How does signalment aid clinical work up of joint disease?

Answer 11

Puppies = instability, senior = osteoarthritis
GSD = hip dysplasia, Labrador = elbow dysplasia, Greyhounds = erosive

Question 12

What history needs to be ascertained when investigating joint disease?

Answer 12

Single or multiple limb
Intermittent, before or after exercise, exercise intolerance
Travel history increases chance of infectious polyarthritis
Parasites
Systemic disease

Question 13

What should be looked at on the clinical exam of a joint disease work up?

Answer 13

Lameness on one/multiple limbs (severity, specific postures/movements), systemic signs present such as fever/lethargy/anorexia/collapse, look for fever/heart murmur/masses, on orthopaedic exam look for joint effusion/buttress/muscle atrophy/pain/heat/decreased ROM/instability and crepitus, rule out neurological causes

Question 14

What diagnostics can be used to work up joint disease?

Answer 14

Radiography, Arthrocentesis, Joint fluid analysis, Serology, Rheumatoid factor, ANA titres, Image body cavities, CSF/muscle biopsy

Question 15

What is looked at on radiographs when investigating joint disease?

Answer 15

Joint capsule, bony relationships, bone density, subchondral bone, calcification and osteophytes and enthesiophytes

Question 16

How is arthrocentesis used in the work up of joint disease?

Answer 16

If only one joint just do that one but at least 3 if polyarthropathy
Perform under sedation/GA using sterile technique, small syringe and needle and have slides, EDTA tube and blood culture media ready

Question 17

Why perform a cell count on joint fluid?

Answer 17

To differentiate between inflammatory and non-inflammatory arthritis

Question 18

Why is cytology of joint fluid useful in investigating joint disease?

Answer 18

Synoviocytes are normal, neutrophils are inflammatory and macrophages are non-inflammatory
Can see other cells such as bacteria/fungi
Haemophagocytosis can be diagnosed

Question 19

What chemical analysis can be performed on joint fluid?

Answer 19

Glucose levels are decreased in septic arthritis

TP increases in inflammatory arthritis

Question 20

How reliable is joint fluid culture? How can you improve the technique?

Answer 20

23% negative in spite of infection being present so use blood culture media to try and improve or perform a synovial membrane biopsy

Question 21

What infectious agents should be looked at for serology of joint disease?

Answer 21

Lyme’s disease, Ehrlichiosis or Leishmania

Question 22

What is test for rheumatoid factor?

Answer 22

Antibodies against IgG

Question 23

What does ANA stand for in ANA titre?

Answer 23

Antinuclear antibodies