Sodium MRI was used for the follow-up of patients with cartilage lesions at 7T. MRI was obtained at baseline, 8-days, 3-months and 6-months follow-up. Regions-of-interest evaluations were performed in weight-bearing, non-weight-bearing and lesion area of femoral cartilage. Sodium values were significantly lower in lesion than in weight-bearing and non-weight-bearing regions at all follow-up measurements. On the other hand, weight-bearing and non-weight-bearing cartilage regions showed stable sodium values over the follow-up time. Sodium imaging allows noninvasive in vivo monitoring of changes in cartilage GAG content and thus can be useful for the evaluation of cartilage degeneration or cartilage regenerating therapies.