Joint Disorders

Question 1

Synovial fluid analysis

MSU is seen was what color when parallel to slow ray?

Calcium pyrophosphate is see in what color when parallel to slow ray?

What does the Mucin clot evaluates?

Answer 1

Routine studies

•White blood cell count and differential, crystal analysis, mucin clot, culture, Gram stain

2.Crystal identification

a.Monosodium urate (MSU)

MSU crystals: monoclinic; negative birefringence (yellow when parallel to slow ray).

(1) Needle-shaped (monoclinic) crystal
(2) Special polarization shows negative birefringence.

Calcium pyrophosphate

Calcium pyrophosphate: monoclinic-like/triclinic; positive birefringence (blue when parallel to slow ray)

(1) Monoclinic-like or triclinic (rhomboid) crystals
(2) Special polarization shows positive birefringence.

•Crystal is blue when parallel to the slow ray.

c.Mucin clot

(1)The test evaluates joint viscosity.

(2)Acid added to synovial fluid causes _hyaluronic acid to clo_t.

•*Hyaluronic acid is the normal joint lubricant.

(3) Poor clot formation reflects decreased hyaluronic acid.

•Sign of joint inflammation

Question 2

What are the classes of joint disorders?

Answer 2

Question 3

Signs and symptoms of joint disease?

Morning stiff-ness is characteristic of?

Answer 3

Question 4

Osteoarthritis

What is osteoarthritis?

What are some common sites where it occurs?

What is ochronosis (alkaptonuria)?

Answer 4

Question 5

Osteoarthritis

Pathogenesis:

Citokines activate what in OA?

Is there ankylosis?

Answer 5

Components of normal articular cartilage

Articular cartilage: proteoglycans, type II collagen

(1) Proteoglycans that provide elasticity**
(2) Type II collagen that provides tensile strength**
b. In OA, cytokines activate metalloproteinases

–>Causes degradation of proteoglycans and collagen

c.Joint findings

(1) Erosion and clefts in articular cartilage
(2) Reactive bone formation occurs at the joint margins (osteophytes)

OA: osteophytes at joint margins

•Causes a slight increase in serum alkaline phosphatase

(3) Subchondral cysts

OA: clefts, subchondral cysts

(4) Bone eventually rubs on bone.

•This produces dense, sclerotic bone.

(5) No ankylosis (fusion) of the joint

OA: no joint fusion

(6) Joint mice

•Refers to fragments of articular cartilage that break free into the joint space

Question 6

Osteoarthritis

Clinical findings:

What is the most common complaint?

What occurs after inactivity?

What does it usually involves in hands?

Answer 6

Question 7

FA:

Osteoarthritis

Answer 7