Figure 7. AFM measured frictional coefficient of normal human articular cartilage in range of (A) HA (no of observation = 16) and (B) γ–globulin (no of observation = 10) concentration.

Increase in HA concentrations shows no significant changes in frictional coefficient of normal articular cartilage samples, while γ–globulin depicts concentration based effect. The frictional coefficient values are from measurements at different locations on two samples of normal human cartilage from a single femoral head. Vertical bars represent 95% of confidence interval. *P<0.01, **P<0.0001, and ns (no significance).