The Mechanism of Lubrication in Cartilage
This project is supported by the Oklahoma Center for the Advancement of Science and Technology (OCAST).
Mr. Liu Shi is conducting this research.
Rationale
Articular cartilage provides lubrication in human joints, but it can easily be damaged by traumatic activities, as well as denatured by arthritis. Being an avascular tissue, articular cartilage has a limited self-repairing ability and current non-surgical treatments for the compromised tissue fail to provide long-term healing effects. The only viable route to symptomatic arthritis is the surgical replacement of the impaired joints. 500,000 total joint replacements are practiced yearly in the US. More will be as the population ages.
We recognize that at present little is known about the mechanism by which lubrication occurs between cartilage surfaces. Our hypothesis is that once we understand such mechanism we will be able to design 'molecular lubricants' that, once injected in compromised joints, will alleviate mild osteoarthritis symptoms and avoid (or delay) the surgical treatment.
Our preliminary results indicate that the friction coefficient between two cartilage specimens sliding on each other depends on many factors, including the ionic strength of the solution in which the specimens are immersed in. More importantly, it appears that for cartilage to provide good lubrication (i.e., low friction coefficient) the pores found within the material need to be swallen with aqueous solution. We now seek to devise methods for keeping such pores swallen under normal locomotion activities.