Figure 3:

Sagittal intermediate-weighted fast spin-echo MR images of the right knee in a 49-year-old woman from the OAI incidence cohort show a patellar lesion that progressed with the CaLS system but not with the WORMS or BLOKS systems. At both, A, baseline and, B, 24-month follow-up, the lesion was scored as WORMS grade 3 and BLOKS grade 2. With the CaLS system, the lesion measured 11 mm at baseline and had a partial thickness of less than 50%; at 24-month follow-up, the lesion measured 14 mm and had a partial thickness of more than 50%.