2 Clinical Manifestations of and Diagnostic Tests for Joint Disorders

1. Lameness

2. Gait Abnormality

Animals with joint disease commonly present with what history?

• One joint/limb = traumatic or developmental

• Multiple joints/limbs = degenerative or inflammatory

If the lameness is traumatic or developmental VS degenerative or inflammatory, how many joints/limbs are involved?

1. Inflammatory

   1. Infectious (Borrelia burgdoferi)

   2. Non-infectious

      1. Erosive (rheumatoid arthritis)

      2. Nonerosive (IMPA, SLE)

2. Non-inflammatory

   1. Developmenal (UAP)

   2. Degenerative (hip dysplasia)

   3. Neoplastic

   4. Traumatic processes

What are the two types of disorders affecting joints?

FALSE: this is true for inflammatory diease

TRUE OR FALSE: Noninflammatory diseases typically show signs of systemic disease with multiple joints affected.

Effusion (fluid accumulation within a joint space or body cavity)

What is happening here?

1. Trauma

2. Panosteitis (age dependent/inflammation of long bones)

3. HOD: Hypertrophic Osteodystrophy (age dependent)

4. Osteomyelitis (infection of bone)

5. Bone neoplasia

You do a physical exam and there is pain upon palpation of the bones. What are some differentials?

1. Myositis

2. Strain/Sprain

You do a physical exam and there is pain upon palpation of the muscles. Give some differentials

Spinal cord or vertebral abnormalities

• IVDD

• intracranial disease (wide range of conditions that affect skull and surrounding structures)

• meningitis

• polyarthritis

You do a physical exam and there is pain upon palpation of the neck. Give some differentials.

Spinal cord or vertebral abnormalities

• IVDD

• discospondylitis (infection of intervertebral discs and endspace)

• intervertebral facet joint inflammation

You do a physical exam and there is pain upon palpation of the spine. Give some differentials

*RADIOGRAPH*, maybe also CT or ultrasound

• Also used when joint palpation reveals crepitation, instability or a restricted range of motion

Name some diagnostic imaging tools that can be used when only ONE joint is affected

Arthrocentesis and synovial fluid analysis

Name some diagnostic imaging tools that can be used when at least THREE TO FOUR joints are affected

If polyarthritis is suspected

When should synovial fluid should be analyzed from at least 3-4 joints?

FALSE: while arthrocentesis IS great for its minimal risk and high diagnostic yield, you ALWAYS aseptically prepare and wear gloves

TRUE OR FALSE: arthrocentesis is a great procedure for multiple joints because there is minimal risk with high diagnostic yield AND minimal aseptic requirements.

Thick, viscous fluid, clear to slightly yellow, high content of hyaluronic acid and lubricin

Describe normal synovial fluid

Normal synovial fluid

Which structure's primary function is to lubricate articular surfaces and facilitate movement within the joint

Normal

Describe this joint fluid

Noninflammatory

Describe this joint fluid

Inflammatory

Describe this joint fluid

Septic

Describe this joint fluid

Hemorrhage

Describe this joint fluid

1. LEAST noninflammatory

2. inflammatory

3. septic

4. MOST hemorrhagic

List the following joint fluid conditions in order of increasing protein and cell count:

noninflammatory

hemorrhagic

septic

inflammatory

NORMAL = string effect

Is this a normal characteristic of joint fluid? What is it called when this happens?

No more than 3 WBC per 40x field

Less than 10% neutrophils

Mix of large and small mononuclear cells

TP less than 2.5

(if 1 neutrophil/500 RBCs = blood contamination)

What should NORMAL joint or synovial fluid look like under a microscope?

DJD and acute trauma

If you see joint fluid with less than 3.5^2 TP and total nucleated cell counts less than 5.0 what should you be expecting?

Inflammatory joint disease (like immune mediated or infectious)

If you see joint fluid with more than 2.5^2 TP and total nucleated cell counts more than 5.0 what should you be expecting?

Neutrophils

Which cells increases in number as the inflammation in the joint becomes more severe?

1. monocytes, macrophages (remember monocytes have "holes eating thru cytoplasm", and are normally a pink/purple color)

2. noninflammatory (because of monocytes)

3. degenerative = arthritis or cruciate rupture

This is synovial fluid from a canine.

1. what cells are you seeing

2. inflammatory or noninflammatory?

3. name a common joint disease associated with this cytology? differentials?

1. these are neutrophils

2. because excessive neutrophils are present = inflammatory

3. infectious (ehrlicia, anaplasma, RMSF) and immune mediated (polyarthritis)

This synovial fluid was taken from the carpus of a painful adult dog with a fever.

1. what are these cells

2. inflammatory or noninflammatory?

3. differentials?

Carpus, tarsus, stifle, elbow

Where do you take joint taps from?

1. inflammatory

(this is actually polyarthritis, lupus erythmatosis)

This is joint fluid taken from an older cat. Describe what you see

1. inflammatory or noninflammatory?

Note: ragocytes are neutrophils in synovial fluid that contains cytoplasmic inclusions

1. monocytes (fluffy with some vaculoes in them) = macrophages

2. noninflammatory based on the fact there are macrophages present

This is from a dog joint with chronic forelimb lameness

1. what kinds of cells do you see?

2. inflammatory or noninflammatory?

1. septic joint (because you see the bacteria being phagocytized by neutrophils) = inflammatory joint disease

2. RBC (maybe some contamination) and neutrophils plus one lymphocyte

This is from a horse joint. Describe what you see

1. inflammatory or noninflammatory?

2. cells?