Synovial Fluids Flashcards
Definition
Fluids that fill joint spaces
Resembles egg white
Joint Anatomy
Movable joints composed cartilage and fibrous capsule lined with a membrane
Membrane Anatomy
Composed of 2 cell types
- Phagocytic cells
- Cells that secrete hyaluronic acid
Production of fluid
Ultrafiltrate of plasma (macromolecules restricted)
Hyaluronic Acid secreted into fluid
Hyaluronic Acid
Large molecular weight mucopolysaccharide
High Viscosity
Fluid Function
Lubrication of joint
Supplies nutrients to cartilage
Fluid Collection
Aseptic needle aspiration
- Arthrocentesis
Tubes for Collection
Sterile - microbiology
Heparin - Chemistry/immunology/crystals
EDTA - Cell count and differential
Synovial Fluid STAT
45 minutes
Synovial Fluids Appearance
Color
Clarity
Volume
Normal Color
Colorless or pale yellow
Normal Clarity
Clear and no clots
Volume
Varies
Normal knee = <3.5 mL
Counting Method
Same as CSF
No Acid Diluents
Normal TNC/cumm
<200
Normal RBC/cumm
<2,000
Normal Differential
Primarily Mononuclear Cells
<25% neutrophils
Crystal Analysis
Primarily Uric Acid
Calcium Pyrophosphate
Cholesterol
Light Analysis of Crystals
Polarized light
Compensated Polarized
Color Appearance
Blue or yellow depending upon type and orientation