Figure 4.

The density of the healthy, catabolic and EPOR-active chondrocytes (C(r, t), S_T(r, t), S_A(r, t)) at t = 2, 4, 6, 8, 10 days with ε = 0.8 and σ_P = 4.2 · 10⁻⁵ (heavy strain with low EPO production). With high strain we have cell death further from the strike zone and our penumbra (the region dominated by S_T and S_A) has widened compared to the low and medium strain cases, resulting in a much larger lesion.