SYNOVIAL FLUID
This topic has been asked in Physiology many times , therefore I will be mentioning the highlights here :
It is an ultradialysate of plasma secreted by synovial capillaries and modified by the secretory activities of type B synoviocytes
These B cells serete Hyaluronic acid – protein complex that gives the synovial fluid its viscosity and lubricating properties
Colour = pale yellow , clear
Location = intra articular
pH = 7.3 to 7.6
Lacks fibrinogen and thus does not clot on its own
String Phenomenon = it is sufficiently viscous that droplets expelled from a needle tip fall in a long string.
Lab . analysis = sterile culture
Specific gravity = 1.008 – 1.015
WBC’s = <100/mm3
Protein content = 20 – 200 mg/ml
No crystals
If WBC content of the synovial fluid increases, it is indicative of different types of disorders as follows :
| WBC Content | Disorders of Joint |
| <200 | NORMAL |
| 200 – 300 | NON INFLAMMATORY (osteoarthritis) |
| 2000 – 75,000 | INFLAMMATORY (Rhematoid arthritis and Gout) |
| >1,00,000 | PURULENT / INFECTIOUS (Septic arthritis) |
thank u 🙂
maximum amount in knee joint 0.5 to 4 ml normally