Figure 3
Wear score vs. Implantation time. Medial compartment wear score plotted against implantation time (a) and the index of use as calculated by the product of numeric activity level and implantation time in months (b). Partial wear score consisting of fatigue type wear plotted against the index of use (c). R2 in model (b) and (c) is improved compared to model (a) indicating that (b) and (c) are superior in explaining wear score variation.