Patients treated for knee disorders were included in this study. They were examined clinically (Lequesne and Tegner scores) and by standard X-ray investigation. Patients underwent a surgical procedure, either arthroscopy or knee replacement. At the initial phase of surgery, a sample of cartilage was taken for laboratory examination. Progression of the disorder and the clinical examination was correlated with the actual state of the cartilage using a novel fluorescence approach. The intrinsic fluorescence of cartilages was shown as a suitable and sensitive method for detection of the actual state of cartilages because the correlation with X-ray examination and clinical status was found. Intrinsic fluorescence properties of cartilages from patients with chondropathy and osteoarthritis were described and found to be age-dependent. We also observed a higher concentration of advanced glycation end products due to inflammatory and/or degenerative processes in the cartilage. In addition, acute pathological changes due to diseases such as meniscal lesions or anterior cruciate ligament rupture caused a significant increase of formation of advanced glycation end products even in the group of young patients. In fact, such an observation could be crucial and important for the detection of knee conditions suspected of early meniscal and/or ACL lesions especially among young patients., M. Handl, E. Filová, M. Kubala, Z. Lánský, L. Koláčná, J. Vorlíček, T. Trč, M. Pach, E. Amler., and Obsahuje bibliografii a bibliografické odkazy