Synovial Fluid Flashcards
viscous liquid found in the cavities of the movable joints
Synovial fluid/ joint fluid
The synovial membrane contains specialized cells called
Synoviocytes
macrophage-like cells located in the superficial layer of the synovial membrane
Type A cells
play an important role in phagocytosis.
Type A cells
fibroblast-like cells with prominent endoplasmic reticulum
Type B cells
reduce friction between the bones during joint movement
smooth articular cartilage and synovial fluid
formed as an ultrafiltrate of plasma across the synovial membrane.
Synovial fluid
synoviocytes secrete a mucopolysaccharide containing
hyaluronic acid and a small amount of protein
Damage to the articular membranes produces pain and stiffness in the joints, collectively referred to as a
arthritis.
Synovial fluid is collected from a joint by needle aspiration
Arthrocentesis
Volume Normal Synovial Fluid Values
<3.5 mL
Color Normal Synovial Fluid Values
Colorless to pale yellow
Clarity Normal Synovial Fluid Values
Clear
Viscosity Normal Synovial Fluid Values
High; Able to form a string
4-6 cm long
Leukocyte count Normal Synovial Fluid Values
<200 cells/uL
Neutrophils count Normal Synovial Fluid Values
<25% of the differential
Glucose: plasma difference Normal Synovial Fluid Values
<10 mg/dI lower than the blood
glucose level
Total protein Normal Synovial Fluid Values
<3 g/dL
Lactate Normal Synovial Fluid Values
<25.0 mg/dL
Tube 1
Red stopper tube chemical or immunologic analysis.
Tube 3
Sodium heparin (green), sodium polyanethol sulfonate (yellow stopper) for microbiological studies.
Synovial fluid viscosity comes from
polymerization of the hyaluronic acid
Hyaluronate polymerization can be measured using a
Ropes, or mucin clot test.
group 1
Non inflammatory
Tube 2
Sodium heparin, EDTA for hematology
Gram stain and culture Required Tube Type
Sterile sodium heparin or sodium
polyanethol sulfonate
Cell counts Required Tube Type
Sodium heparin or liquid ethylenediaminetetraacetic acid
(EDTA)
Glucose analysis Required Tube Type
Sodium fluoride or nonanticoagulated
Glucose analysis Required Tube Type
Sodium fluoride or nonanticoagulated
Type 2 classification
Inflammatory
Type 3 group classification
Septic
Group 4 classification
Hemorrhagic
The color becomes a deeper yellow in the presence of
noninflammatory and inflammatory effusions
The color may have a greenish tinge with
Bacterial infection
vacuolated noninflammatory and inflammatory effusions
Neutrophages
neutrophils with small, dark cytoplasmic granules
Ragocytes
hemosiderin granules are seen in cases of
pigmented villonodular synovitis
The primary crystals seen in synovial fluid
monosodium urate (uric acid) (MSU), calcium pyrophosphate dihydrate (CPPD)
Polymorphonuclear leukocyte
Neutrophil
Significance of neutrophil
Bacterial sepsis, crystal induced inflammation
Mononuclear leukocyte Nonseptic inflammation
Lymphocyte
- Large mononuclear leukocyte, may be vacuolated
- normal and viral infections
Macrophage (monocyte)
Similar to macrophage, but may be multinucle-
ated, resembling a mesothelial cell
Synovial lining cell
Normal, disruption from arthrocentesis
Synovial lining cell
Neutrophil containing characteristic ingested
“round body”
LE cell
Vacuolated macrophage with ingested
neutrophils
Reiter cell
Neutrophil with dark cytoplasmic granules
containing immune complexes
RA cell (ragocyte)
Large, multinucleated cells
Cartilage cells
Macroscopically resemble polished rice
Microscopically show collagen and fibrin
Rice bodies
Refractile intracellular and extracellular globules
Stain with Sudan dyes
Fat droplets
Inclusions within clusters of synovial cells
Hemosiderin
