The Hip book
Home » Joints » Knee » Hyaluronic Acid

Hyaluronic Acid

(see also: osteoarthritis of the knee)

Discussion

function

  • acts as lubricant and shock absorber;
  • acts as barrier permitting metabolites to pass thru it by diffusion but resists penetration by bacteria and other infectious agents;
  • most hygroscopic molecule in the human body

presence in cartilage

  • amount in cartilage is variable but usually represents less than 1% of total glycosaminoglycans;
  • can be present in a free state, but it is usually found as a part of proteoglycan aggregates in cartilage;
  • maintenance of physico-chemical characteristics of cartilage extracellular matrix

presence in synovial fluid »

  • in joint fluid, hyaluronic acid is synthesized in synovial membrane;
  • hyaluronate in synovial fluid is an extended glycosaminoglycan and a lubricating glycoprotein;
  • sheer stiffness (determines elastic behavior) of synovial fluid is derived from the entanglement of these long-chain molecules and remains constant;
  • may have an antiinflammatory effect and an antioxidative effect

References