The present case-control study included as cases 24 athletes with anterior knee pain, and 17 controls, matching the cases according to gender and age. All cases had their most symptomatic knee examined by magnetic resonance imaging (MRI). Among controls one knee was chosen for examination at random. The MRI of the patella showed articular cartilage lesions in 17 out of 24 cases, whereas among the controls 4 out of 17 had articular cartilage lesions. (Odds Ratio 7.9 (95% confidence interval 1.9-33)). However, presence of articular cartilage lesions was not associated with duration of symptoms or intensity of the anterior knee pain. The present study showed a significant positive association between presence of articular cartilage lesions in the patella and presence of anterior knee pain, but further studies are needed to examine the relationship in detail.